The document summarizes research on the Kepler-9 planetary system. It finds that Kepler-9b and Kepler-9c are Saturn-sized planets with orbital periods of 19.24 and 39.08 days, respectively. Kepler-9d is a super-Earth with a period of 1.59 days. The Kepler-9 system was the first discovered using the transit method to have transit time variations (TTVs) detected for its planets. The research uses transit and radial velocity data to determine various properties of the three planets, including radius, orbital period, TTV, semi-major axis, mass, and density. It finds the first multi-planetary system where TTVs were detected, adding scientific value.
Science with small telescopes - exoplanetsguest8aa6ebb
The search for extrasolar planets has become one of the most attractive problems in modern astrophysics. The biggest observatories in the world are involved in this task as well as little amateur instruments. There is also a huge variety of astronomical methods used for their investigation. Here I present the projects for searching for exoplanets by transit method and our observations of the planet WASP-2b. We observed a transit on 3/4 August 2008 with a 354 mm Schmidt-Cassegrain Celestron telescope and CCD SBIG STL 11000M camera. By precise photometry made using MaximDL software we obtained the light curve of the star system. Decrease of brightness by 0.02m is detected. Analyzing our data we estimate the radius of the planet and inclination of its orbit. Our results are in good correlation with the published information in literature.
This document describes a method for searching Kepler K2 lightcurves for transiting planets orbiting eclipsing binary star systems (circumbinary planets). The researchers search K2 data to identify eclipsing binaries, then remove the binary signal to search for planetary transits. They test two methods for removing the binary signal: clipping eclipses, and dividing by the moving median. Detection efficiency is determined by injecting artificial planets and measuring recovery rates with respect to planet parameters. Moving median removal yields a higher detection efficiency of around 20% compared to 11% for eclipse clipping.
The canarias einstein_ring_a_newly_discovered_optical_einstein_ringSérgio Sacani
This document reports the discovery of a newly discovered optical Einstein ring (ER) called the "Canarias Einstein Ring". It was discovered serendipitously in imaging data from the Dark Energy Camera. Follow-up spectroscopy with the Gran Telescopio CANARIAS confirmed the nature of the system, with the lens being an early-type galaxy at a redshift of z=0.581 and the source being a starburst galaxy at z=1.165. Analysis of the system determined the Einstein radius to be 2.16 arcseconds and the total enclosed mass producing the lensing effect to be 1.86 ± 0.23 × 1012 solar masses.
This document summarizes the discovery of HIP 116454b, the first planet discovered by the Kepler K2 mission. The host star HIP 116454 is a bright, nearby K-dwarf observed during the K2 engineering test in February 2014. Analysis of the K2 photometry using a new technique revealed a single transit, indicating a super-Earth sized planet with a radius of 2.53 R⊕. Follow-up radial velocity observations and photometry from other telescopes confirmed the planet and refined its properties to a mass of 11.82 M⊕ and orbital period of 9.1 days. This makes HIP 116454b one of the few super-Earth exoplanets around bright stars amenable to detailed
An earth sized_planet_with_an_earth_sized_densitySérgio Sacani
1) Researchers observed the exoplanet Kepler-78b using the HARPS-N spectrograph to measure its mass.
2) They measured Kepler-78b's mass to be 1.86 Earth masses, giving it a density similar to Earth, implying a rocky composition of iron and rock.
3) The small size of Kepler-78b makes it the smallest exoplanet yet measured for both mass and radius, establishing that Earth-sized planets can be terrestrial.
The kepler 10_planetary_system_revisited_by_harpsSérgio Sacani
This document discusses observations of the Kepler-10 planetary system made with the HARPS-N spectrograph. The observations resulted in improved precision for the masses of Kepler-10b and Kepler-10c. Kepler-10b's mass was determined to be 3.33 ± 0.49 Earth masses, confirming its rocky composition. Kepler-10c's mass of 17.2 ± 1.9 Earth masses makes it the first strong evidence of a class of more massive solid Neptune-sized planets with longer orbital periods. The improved mass measurements will help constrain models of the internal structure and composition of these planets.
Detection of solar_like_oscillations_in_relies_of_the_milk_way_asteroseismolo...Sérgio Sacani
Asteroseismic constraints on K giants make it possible to infer radii, masses and ages of tens
of thousands of field stars. Tests against independent estimates of these properties are however
scarce, especially in the metal-poor regime. Here, we report the detection of solar-like
oscillations in 8 stars belonging to the red-giant branch and red-horizontal branch of the globular
cluster M4. The detections were made in photometric observations from the K2 Mission
during its Campaign 2. Making use of independent constraints on the distance, we estimate
masses of the 8 stars by utilising different combinations of seismic and non-seismic inputs.
When introducing a correction to the Δν scaling relation as suggested by stellar models, for
RGB stars we find excellent agreement with the expected masses from isochrone fitting, and
with a distance modulus derived using independent methods. The offset with respect to independent
masses is lower, or comparable with, the uncertainties on the average RGB mass
(4 − 10%, depending on the combination of constraints used). Our results lend confidence to
asteroseismic masses in the metal poor regime. We note that a larger sample will be needed
to allow more stringent tests to be made of systematic uncertainties in all the observables
(both seismic and non-seismic), and to explore the properties of RHB stars, and of different
populations in the cluster.
Science with small telescopes - exoplanetsguest8aa6ebb
The search for extrasolar planets has become one of the most attractive problems in modern astrophysics. The biggest observatories in the world are involved in this task as well as little amateur instruments. There is also a huge variety of astronomical methods used for their investigation. Here I present the projects for searching for exoplanets by transit method and our observations of the planet WASP-2b. We observed a transit on 3/4 August 2008 with a 354 mm Schmidt-Cassegrain Celestron telescope and CCD SBIG STL 11000M camera. By precise photometry made using MaximDL software we obtained the light curve of the star system. Decrease of brightness by 0.02m is detected. Analyzing our data we estimate the radius of the planet and inclination of its orbit. Our results are in good correlation with the published information in literature.
This document describes a method for searching Kepler K2 lightcurves for transiting planets orbiting eclipsing binary star systems (circumbinary planets). The researchers search K2 data to identify eclipsing binaries, then remove the binary signal to search for planetary transits. They test two methods for removing the binary signal: clipping eclipses, and dividing by the moving median. Detection efficiency is determined by injecting artificial planets and measuring recovery rates with respect to planet parameters. Moving median removal yields a higher detection efficiency of around 20% compared to 11% for eclipse clipping.
The canarias einstein_ring_a_newly_discovered_optical_einstein_ringSérgio Sacani
This document reports the discovery of a newly discovered optical Einstein ring (ER) called the "Canarias Einstein Ring". It was discovered serendipitously in imaging data from the Dark Energy Camera. Follow-up spectroscopy with the Gran Telescopio CANARIAS confirmed the nature of the system, with the lens being an early-type galaxy at a redshift of z=0.581 and the source being a starburst galaxy at z=1.165. Analysis of the system determined the Einstein radius to be 2.16 arcseconds and the total enclosed mass producing the lensing effect to be 1.86 ± 0.23 × 1012 solar masses.
This document summarizes the discovery of HIP 116454b, the first planet discovered by the Kepler K2 mission. The host star HIP 116454 is a bright, nearby K-dwarf observed during the K2 engineering test in February 2014. Analysis of the K2 photometry using a new technique revealed a single transit, indicating a super-Earth sized planet with a radius of 2.53 R⊕. Follow-up radial velocity observations and photometry from other telescopes confirmed the planet and refined its properties to a mass of 11.82 M⊕ and orbital period of 9.1 days. This makes HIP 116454b one of the few super-Earth exoplanets around bright stars amenable to detailed
An earth sized_planet_with_an_earth_sized_densitySérgio Sacani
1) Researchers observed the exoplanet Kepler-78b using the HARPS-N spectrograph to measure its mass.
2) They measured Kepler-78b's mass to be 1.86 Earth masses, giving it a density similar to Earth, implying a rocky composition of iron and rock.
3) The small size of Kepler-78b makes it the smallest exoplanet yet measured for both mass and radius, establishing that Earth-sized planets can be terrestrial.
The kepler 10_planetary_system_revisited_by_harpsSérgio Sacani
This document discusses observations of the Kepler-10 planetary system made with the HARPS-N spectrograph. The observations resulted in improved precision for the masses of Kepler-10b and Kepler-10c. Kepler-10b's mass was determined to be 3.33 ± 0.49 Earth masses, confirming its rocky composition. Kepler-10c's mass of 17.2 ± 1.9 Earth masses makes it the first strong evidence of a class of more massive solid Neptune-sized planets with longer orbital periods. The improved mass measurements will help constrain models of the internal structure and composition of these planets.
Detection of solar_like_oscillations_in_relies_of_the_milk_way_asteroseismolo...Sérgio Sacani
Asteroseismic constraints on K giants make it possible to infer radii, masses and ages of tens
of thousands of field stars. Tests against independent estimates of these properties are however
scarce, especially in the metal-poor regime. Here, we report the detection of solar-like
oscillations in 8 stars belonging to the red-giant branch and red-horizontal branch of the globular
cluster M4. The detections were made in photometric observations from the K2 Mission
during its Campaign 2. Making use of independent constraints on the distance, we estimate
masses of the 8 stars by utilising different combinations of seismic and non-seismic inputs.
When introducing a correction to the Δν scaling relation as suggested by stellar models, for
RGB stars we find excellent agreement with the expected masses from isochrone fitting, and
with a distance modulus derived using independent methods. The offset with respect to independent
masses is lower, or comparable with, the uncertainties on the average RGB mass
(4 − 10%, depending on the combination of constraints used). Our results lend confidence to
asteroseismic masses in the metal poor regime. We note that a larger sample will be needed
to allow more stringent tests to be made of systematic uncertainties in all the observables
(both seismic and non-seismic), and to explore the properties of RHB stars, and of different
populations in the cluster.
An earth sized_planet_in_the_habitable_zone_of_a_cool_starSérgio Sacani
This document describes the discovery of Kepler-186f, an Earth-sized planet orbiting within the habitable zone of its host star Kepler-186, a cool M-dwarf star. Kepler-186f receives a similar amount of stellar radiation as Earth and models suggest it could harbor liquid water on its surface if it has an Earth-like atmosphere. At 1.11 times the size of Earth, Kepler-186f is the smallest planet discovered to date within the habitable zone of its star. The five planets orbiting Kepler-186, including Kepler-186f, likely formed from the protoplanetary disk around the star and provide the first Earth-sized candidate for a habitable world.
This study analyzed transit observations of the Neptune-mass exoplanet GJ 436b taken with the Hubble Space Telescope. The transmission spectrum was found to be featureless, ruling out cloud-free hydrogen-dominated atmosphere models with high significance. The flat transmission spectrum is consistent with either an atmosphere containing high-altitude clouds located at a pressure of around 1 millibar, or a relatively hydrogen-poor atmosphere with 3% hydrogen and helium by mass. Bayesian atmospheric modeling showed that cloudy hydrogen-dominated or high-metallicity hydrogen-poor atmospheres provide the best fits to the data. Further observations are needed to distinguish between these scenarios.
We present deep optical images of the Large and Small Magellanic Clouds (LMC and SMC) using
a low cost telephoto lens with a wide field of view to explore stellar substructure in the outskirts
of the stellar disk of the LMC (r < 10 degrees from the center). These data have higher resolution
than existing star count maps, and highlight the existence of stellar arcs and multiple spiral arms in
the northern periphery, with no comparable counterparts in the South. We compare these data to
detailed simulations of the LMC disk outskirts, following interactions with its low mass companion,
the SMC. We consider interaction in isolation and with the inclusion of the Milky Way tidal field.
The simulations are used to assess the origin of the northern structures, including also the low density
stellar arc recently identified in the DES data by Mackey et al. (2015) at ∼ 15 degrees. We conclude
that repeated close interactions with the SMC are primarily responsible for the asymmetric stellar
structures seen in the periphery of the LMC. The orientation and density of these arcs can be used to
constrain the LMC’s interaction history with and impact parameter of the SMC. More generally, we
find that such asymmetric structures should be ubiquitous about pairs of dwarfs and can persist for
1-2 Gyr even after the secondary merges entirely with the primary. As such, the lack of a companion
around a Magellanic Irregular does not disprove the hypothesis that their asymmetric structures are
driven by dwarf-dwarf interactions.
1) Researchers observed 15 transits of the exoplanet GJ 1214b using the Hubble Space Telescope to measure its transmission spectrum from 1.1 to 1.7 microns.
2) The transmission spectrum was featureless, inconsistent with cloud-free atmospheres dominated by water, methane, carbon monoxide, nitrogen, or carbon dioxide.
3) The most likely explanation for the featureless spectrum is the presence of high-altitude clouds in the planet's atmosphere, which block the transmission of stellar light through the lower atmosphere.
A rock composition_for_earth_sized_exoplanetsSérgio Sacani
1) Researchers measured the mass of Kepler-78b, an Earth-sized exoplanet orbiting its host star every 8.5 hours, to be 1.69 ± 0.41 M⊕ using Doppler spectroscopy of the star's radial velocity variations.
2) Given the planet's radius of 1.20 ± 0.09 R⊕, its mean density of 5.3 ± 1.8 g/cm3 is similar to Earth's, suggesting a rocky composition of iron and rock.
3) Kepler-78b is the smallest exoplanet yet characterized with both an accurate mass and radius measurement, extending measurements of planetary composition into the size range of Earth and Venus.
Are we alone? How prevalent is intelligent life in the Universe? How are the recent exoplanet discoveries by NASA's Kepler mission bearing on this question?
The ASTRODEEP Frontier Fields catalogues II. Photometric redshifts and rest f...Sérgio Sacani
This document describes a public release of photometric redshifts and galaxy properties from multi-wavelength data in the Abell-2744 and MACS-J0416 galaxy cluster fields observed as part of the Frontier Fields program. Photometric redshifts were estimated using six different methods and have an accuracy of 3-5%. Accounting for gravitational lensing magnification, the H-band number counts agree with CANDELS at bright magnitudes but extend to intrinsically fainter galaxies of H=32-33. The Frontier Fields data allow probing galaxy stellar masses 0.5-1.5 dex lower than in wide fields, including sources with masses of 107-108 solar masses at z>5. Star formation rates can be detected 1
This document analyzes over 1,000 spectra of the Beta Pictoris system obtained between 2003-2011, identifying around 6,000 variable absorption features caused by transiting exocomets. Statistical analysis reveals two distinct populations of exocomets: Population S, which produces shallow absorption lines and consists of old exhausted comets trapped in resonance with a planet; and Population D, which produces deep lines and likely results from recent fragmentation of parent bodies. Physical properties like radial velocity, line width, and orbital parameters differ between the two populations, indicating two separate families of exocomets in the Beta Pictoris system.
A close pair_binary_in_a_distant_triple_supermassive_black_hole_systemSérgio Sacani
This document reports the discovery of a triple supermassive black hole system through radio observations. Very Long Baseline Interferometry observations revealed two flat-spectrum radio cores, labelled J1502SE and J1502SW, within the galaxy J1502S, separated by about 140 parsecs. Analysis of archival data provides further evidence of this close black hole pair through the detection of 'S-shaped' radio emission between the two cores, indicative of jet precession caused by the binary black holes. This is the closest black hole pair yet discovered and demonstrates a new method for finding binary black holes that cannot be spatially resolved with current instruments.
1) The document reports on phase-resolved emission spectroscopy observations of the exoplanet WASP-43b using the Hubble Space Telescope.
2) The observations tracked the planet over three full orbits and measured its thermal emission as a function of orbital phase, allowing the researchers to construct a map of the planet's atmospheric thermal structure.
3) The results found large day-night temperature variations at all measured altitudes, with temperature monotonically decreasing with increasing pressure. A low Bond albedo of 0.07-0.18 and offset of the hottest point from the substellar point were also derived.
A terrestrial planet_candidate_in_a_temperate_orbit_around_proxima_centauriSérgio Sacani
At a distance of 1.295 parsecs,1 the red-dwarf Proxima Centauri (α Centauri C, GL 551,
HIP 70890, or simply Proxima) is the Sun’s closest stellar neighbour and one of the best studied
low-mass stars. It has an effective temperature of only 3050 K, a luminosity of 0.1 per
cent solar, a measured radius of 0.14 R⊙
2 and a mass of about 12 per cent the mass of the
Sun. Although Proxima is considered a moderately active star, its rotation period is 83
days,3 and its quiescent activity levels and X-ray luminosity4 are comparable to the Sun’s. New
observations reveal the presence of a small planet orbiting Proxima with a minimum mass of
1.3 Earth masses and an orbital period of 11.2 days. Its orbital semi-major axis is 0.05 AU,
with an equilibrium temperature in the range where water could be liquid on its surface.5
This document discusses using future full-sky galaxy surveys from space telescopes to probe initial conditions and constrain primordial non-Gaussianity. It proposes launching a space telescope called SPHEREx to conduct a full-sky galaxy spectroscopy survey. This would allow probing the horizon-scale clustering needed to constrain the non-Gaussianity parameter fNL using both the galaxy power spectrum and bispectrum. Current forecasts suggest SPHEREx could achieve an uncertainty of σ(fNL) ~ 0.8 from the power spectrum alone and σ(fNL) ~ 0.2 when also including the bispectrum. However, challenges remain in applying photometric redshift indicators and understanding contributions to the squeezed bispectrum at higher orders.
This document provides information about constants and laws related to gravitational fields that commonly appear on exams for the PAU (University Access Test) in Castilla y León, Spain. It includes the values of gravitational acceleration on Earth (g0), Earth's radius (RT), Earth's mass (MT), and the gravitational constant (G). It then provides example problems applying Kepler's laws and Newton's law of universal gravitation to calculate orbital properties of planets, moons, and satellites. Sample problems calculate orbital periods, velocities, distances, and gravitational accelerations for bodies in the solar system like Jupiter, Mars, Mercury, the Moon, and artificial satellites.
The 19 Feb. 2016 Outburst of Comet 67P/CG: An ESA Rosetta Multi-Instrument StudySérgio Sacani
On 19 Feb. 2016 nine Rosetta instruments serendipitously observed an outburst of gas and dust
from the nucleus of comet 67P/Churyumov-Gerasimenko. Among these instruments were cameras
and spectrometers ranging from UV over visible to microwave wavelengths, in-situ gas, dust and
plasma instruments, and one dust collector. At 9:40 a dust cloud developed at the edge of an image
in the shadowed region of the nucleus. Over the next two hours the instruments recorded a signature
of the outburst that signicantly exceeded the background. The enhancement ranged from 50% of
the neutral gas density at Rosetta to factors >100 of the brightness of the coma near the nucleus.
Dust related phenomena (dust counts or brightness due to illuminated dust) showed the strongest
enhancements (factors >10). However, even the electron density at Rosetta increased by a factor 3
and consequently the spacecraft potential changed from 16V to 20V during the outburst. A
clear sequence of events was observed at the distance of Rosetta (34 km from the nucleus): within 15
minutes the Star Tracker camera detected fast particles ( 25 ms 1) while 100 m radius particles
were detected by the GIADA dust instrument 1 hour later at a speed of 6 ms 1. The slowest
were individual mm to cm sized grains observed by the OSIRIS cameras. Although the outburst
originated just outside the FOV of the instruments, the source region and the magnitude of the
outburst could be determined.
This document summarizes the discovery and characterization of Kepler-432 b, a massive exoplanet in a highly eccentric orbit around a red giant star. Key findings include:
1) Radial velocity measurements from the CAFE spectrograph revealed Kepler-432 b has a mass of 4.87 ± 0.48 MJup and moves in a highly eccentric orbit (e = 0.535 ± 0.030) around its host star.
2) Simultaneous modeling of Kepler photometry and radial velocity data determined Kepler-432 b has a radius of 1.120 ± 0.036 RJup and orbits every 52.5 days.
3) Analysis of high-resolution images found a nearby star
Pawan Kumar Relativistic jets in tidal disruption eventsBaurzhan Alzhanov
- Fast radio bursts (FRBs) are short, intense radio pulses that last about 1 millisecond. One FRB source produced multiple outbursts over several years.
- The leading model is that FRBs originate from young, highly magnetic neutron stars called magnetars. Charged particles are accelerated by magnetic reconnection, producing coherent curvature radiation observed as FRBs.
- FRBs provide insights into neutron star physics and energetic processes in magnetar magnetospheres. Predictions include observing FRB-like bursts at higher frequencies.
Uma equipe de astrofísicos usando o Observatório W. M. Keck no Havaí mediu com sucesso a galáxia mais distante já registrada e o mais interessante, capturou sua emissão de hidrogênio vista quando o universo tinha menos de 600 milhões de anos de vida. Adicionalmente, o método pelo qual a galáxia EGSY8p7 foi detectada dá uma ideia importante sobre como as primeiras estrelas no universo se acenderam depois do Big Bang.
Usando o poderoso espectrógrafo infravermelho do Observatório Keck, chamado MOSFIRE, a equipe datou a galáxia detectando sua linha de emissão Lyman-alpha – uma assinatura do gás hidrogênio quente, aquecido pela forte emissão ultravioleta de estrelas recém-nascidas. Embora, frequentemente seja possível detectar essa assinatura em galáxias próximas da Terra, a detecção da emissão Lyman-alpha nessas grandes distâncias é inesperada, já que ela é facilmente absorvida pelos numerosos átomos de hidrogênio que acredita-se existam no espaço entre as galáxias no nascer do universo. O resultado dá uma nova ideia sobre a reionização cósmica, o processo pelo qual nuvens escuras de hidrogênio foram partidas em seus prótons constituintes e elétrons pelas primeiras gerações de galáxias.
“Nós frequentemente observamos a linha de emissão Lyman-alpha do hidrogênio em objetos próximos já que eles são um dos traçadores mais confiáveis da formação de estrelas”, disse o astrônomo Adi Zitrin, do Instituto de Tecnologia da Califórnia, o Caltech, principal autor do estudo. “Contudo, à medida que penetramos mais fundo no universo, e então voltamos a tempos remotos, o espaço entre as galáxias continha um grande número de nuvens escuras de hidrogênio que absorviam esse sinal”.
The Internal Structure of Asteroid (25143) Itokawa as Revealed by Detection o...WellingtonRodrigues2014
- The authors detected an acceleration in the rotation rate of asteroid (25143) Itokawa through photometric observations spanning 2001 to 2013.
- By measuring rotational phase offsets between observed and modeled lightcurves, they found a YORP acceleration of 3.54 ± 0.38 × 10−8 rad day−2, equivalent to a decrease in the asteroid's rotation period of about 45 ms per year.
- Thermophysical modeling of the detailed shape model from the Hayabusa spacecraft could not reconcile the observed YORP strength unless the asteroid's center of mass is shifted by about 21 m along its long axis. This suggests Itokawa has two components with different densities that merged, either from a
This document contains a spelling list and sentences for students to practice words containing short vowel sounds. The 15-word spelling list includes common words like "part", "hard", "born", and "corn". There are also 5 short practice sentences using some of the words, such as questions about riding a horse, wanting more food, and sitting on a porch.
This spelling list for 5th period contains 15 words ending in -tion and -ture along with 5 sample sentences using some of the words. The words include mixture, nation, section, future, picture, fixture, motion, nature, feature, furniture, action, caution, station, adventure, and tuition. The sentences demonstrate the words being used in contexts like describing the first moon landing, allowing use of a book section, working at a fire station, enjoying sports with action, and replacing a light fixture.
This document contains a spelling list for 4th period with suffixes -ly, -ful, -er, and -or. It includes 15 words with those suffixes for students to study. It also provides 5 sample sentences using some of the spelling words, such as sentences about a visitor, a sailor, cheerful children, running quickly, and being a good helper.
An earth sized_planet_in_the_habitable_zone_of_a_cool_starSérgio Sacani
This document describes the discovery of Kepler-186f, an Earth-sized planet orbiting within the habitable zone of its host star Kepler-186, a cool M-dwarf star. Kepler-186f receives a similar amount of stellar radiation as Earth and models suggest it could harbor liquid water on its surface if it has an Earth-like atmosphere. At 1.11 times the size of Earth, Kepler-186f is the smallest planet discovered to date within the habitable zone of its star. The five planets orbiting Kepler-186, including Kepler-186f, likely formed from the protoplanetary disk around the star and provide the first Earth-sized candidate for a habitable world.
This study analyzed transit observations of the Neptune-mass exoplanet GJ 436b taken with the Hubble Space Telescope. The transmission spectrum was found to be featureless, ruling out cloud-free hydrogen-dominated atmosphere models with high significance. The flat transmission spectrum is consistent with either an atmosphere containing high-altitude clouds located at a pressure of around 1 millibar, or a relatively hydrogen-poor atmosphere with 3% hydrogen and helium by mass. Bayesian atmospheric modeling showed that cloudy hydrogen-dominated or high-metallicity hydrogen-poor atmospheres provide the best fits to the data. Further observations are needed to distinguish between these scenarios.
We present deep optical images of the Large and Small Magellanic Clouds (LMC and SMC) using
a low cost telephoto lens with a wide field of view to explore stellar substructure in the outskirts
of the stellar disk of the LMC (r < 10 degrees from the center). These data have higher resolution
than existing star count maps, and highlight the existence of stellar arcs and multiple spiral arms in
the northern periphery, with no comparable counterparts in the South. We compare these data to
detailed simulations of the LMC disk outskirts, following interactions with its low mass companion,
the SMC. We consider interaction in isolation and with the inclusion of the Milky Way tidal field.
The simulations are used to assess the origin of the northern structures, including also the low density
stellar arc recently identified in the DES data by Mackey et al. (2015) at ∼ 15 degrees. We conclude
that repeated close interactions with the SMC are primarily responsible for the asymmetric stellar
structures seen in the periphery of the LMC. The orientation and density of these arcs can be used to
constrain the LMC’s interaction history with and impact parameter of the SMC. More generally, we
find that such asymmetric structures should be ubiquitous about pairs of dwarfs and can persist for
1-2 Gyr even after the secondary merges entirely with the primary. As such, the lack of a companion
around a Magellanic Irregular does not disprove the hypothesis that their asymmetric structures are
driven by dwarf-dwarf interactions.
1) Researchers observed 15 transits of the exoplanet GJ 1214b using the Hubble Space Telescope to measure its transmission spectrum from 1.1 to 1.7 microns.
2) The transmission spectrum was featureless, inconsistent with cloud-free atmospheres dominated by water, methane, carbon monoxide, nitrogen, or carbon dioxide.
3) The most likely explanation for the featureless spectrum is the presence of high-altitude clouds in the planet's atmosphere, which block the transmission of stellar light through the lower atmosphere.
A rock composition_for_earth_sized_exoplanetsSérgio Sacani
1) Researchers measured the mass of Kepler-78b, an Earth-sized exoplanet orbiting its host star every 8.5 hours, to be 1.69 ± 0.41 M⊕ using Doppler spectroscopy of the star's radial velocity variations.
2) Given the planet's radius of 1.20 ± 0.09 R⊕, its mean density of 5.3 ± 1.8 g/cm3 is similar to Earth's, suggesting a rocky composition of iron and rock.
3) Kepler-78b is the smallest exoplanet yet characterized with both an accurate mass and radius measurement, extending measurements of planetary composition into the size range of Earth and Venus.
Are we alone? How prevalent is intelligent life in the Universe? How are the recent exoplanet discoveries by NASA's Kepler mission bearing on this question?
The ASTRODEEP Frontier Fields catalogues II. Photometric redshifts and rest f...Sérgio Sacani
This document describes a public release of photometric redshifts and galaxy properties from multi-wavelength data in the Abell-2744 and MACS-J0416 galaxy cluster fields observed as part of the Frontier Fields program. Photometric redshifts were estimated using six different methods and have an accuracy of 3-5%. Accounting for gravitational lensing magnification, the H-band number counts agree with CANDELS at bright magnitudes but extend to intrinsically fainter galaxies of H=32-33. The Frontier Fields data allow probing galaxy stellar masses 0.5-1.5 dex lower than in wide fields, including sources with masses of 107-108 solar masses at z>5. Star formation rates can be detected 1
This document analyzes over 1,000 spectra of the Beta Pictoris system obtained between 2003-2011, identifying around 6,000 variable absorption features caused by transiting exocomets. Statistical analysis reveals two distinct populations of exocomets: Population S, which produces shallow absorption lines and consists of old exhausted comets trapped in resonance with a planet; and Population D, which produces deep lines and likely results from recent fragmentation of parent bodies. Physical properties like radial velocity, line width, and orbital parameters differ between the two populations, indicating two separate families of exocomets in the Beta Pictoris system.
A close pair_binary_in_a_distant_triple_supermassive_black_hole_systemSérgio Sacani
This document reports the discovery of a triple supermassive black hole system through radio observations. Very Long Baseline Interferometry observations revealed two flat-spectrum radio cores, labelled J1502SE and J1502SW, within the galaxy J1502S, separated by about 140 parsecs. Analysis of archival data provides further evidence of this close black hole pair through the detection of 'S-shaped' radio emission between the two cores, indicative of jet precession caused by the binary black holes. This is the closest black hole pair yet discovered and demonstrates a new method for finding binary black holes that cannot be spatially resolved with current instruments.
1) The document reports on phase-resolved emission spectroscopy observations of the exoplanet WASP-43b using the Hubble Space Telescope.
2) The observations tracked the planet over three full orbits and measured its thermal emission as a function of orbital phase, allowing the researchers to construct a map of the planet's atmospheric thermal structure.
3) The results found large day-night temperature variations at all measured altitudes, with temperature monotonically decreasing with increasing pressure. A low Bond albedo of 0.07-0.18 and offset of the hottest point from the substellar point were also derived.
A terrestrial planet_candidate_in_a_temperate_orbit_around_proxima_centauriSérgio Sacani
At a distance of 1.295 parsecs,1 the red-dwarf Proxima Centauri (α Centauri C, GL 551,
HIP 70890, or simply Proxima) is the Sun’s closest stellar neighbour and one of the best studied
low-mass stars. It has an effective temperature of only 3050 K, a luminosity of 0.1 per
cent solar, a measured radius of 0.14 R⊙
2 and a mass of about 12 per cent the mass of the
Sun. Although Proxima is considered a moderately active star, its rotation period is 83
days,3 and its quiescent activity levels and X-ray luminosity4 are comparable to the Sun’s. New
observations reveal the presence of a small planet orbiting Proxima with a minimum mass of
1.3 Earth masses and an orbital period of 11.2 days. Its orbital semi-major axis is 0.05 AU,
with an equilibrium temperature in the range where water could be liquid on its surface.5
This document discusses using future full-sky galaxy surveys from space telescopes to probe initial conditions and constrain primordial non-Gaussianity. It proposes launching a space telescope called SPHEREx to conduct a full-sky galaxy spectroscopy survey. This would allow probing the horizon-scale clustering needed to constrain the non-Gaussianity parameter fNL using both the galaxy power spectrum and bispectrum. Current forecasts suggest SPHEREx could achieve an uncertainty of σ(fNL) ~ 0.8 from the power spectrum alone and σ(fNL) ~ 0.2 when also including the bispectrum. However, challenges remain in applying photometric redshift indicators and understanding contributions to the squeezed bispectrum at higher orders.
This document provides information about constants and laws related to gravitational fields that commonly appear on exams for the PAU (University Access Test) in Castilla y León, Spain. It includes the values of gravitational acceleration on Earth (g0), Earth's radius (RT), Earth's mass (MT), and the gravitational constant (G). It then provides example problems applying Kepler's laws and Newton's law of universal gravitation to calculate orbital properties of planets, moons, and satellites. Sample problems calculate orbital periods, velocities, distances, and gravitational accelerations for bodies in the solar system like Jupiter, Mars, Mercury, the Moon, and artificial satellites.
The 19 Feb. 2016 Outburst of Comet 67P/CG: An ESA Rosetta Multi-Instrument StudySérgio Sacani
On 19 Feb. 2016 nine Rosetta instruments serendipitously observed an outburst of gas and dust
from the nucleus of comet 67P/Churyumov-Gerasimenko. Among these instruments were cameras
and spectrometers ranging from UV over visible to microwave wavelengths, in-situ gas, dust and
plasma instruments, and one dust collector. At 9:40 a dust cloud developed at the edge of an image
in the shadowed region of the nucleus. Over the next two hours the instruments recorded a signature
of the outburst that signicantly exceeded the background. The enhancement ranged from 50% of
the neutral gas density at Rosetta to factors >100 of the brightness of the coma near the nucleus.
Dust related phenomena (dust counts or brightness due to illuminated dust) showed the strongest
enhancements (factors >10). However, even the electron density at Rosetta increased by a factor 3
and consequently the spacecraft potential changed from 16V to 20V during the outburst. A
clear sequence of events was observed at the distance of Rosetta (34 km from the nucleus): within 15
minutes the Star Tracker camera detected fast particles ( 25 ms 1) while 100 m radius particles
were detected by the GIADA dust instrument 1 hour later at a speed of 6 ms 1. The slowest
were individual mm to cm sized grains observed by the OSIRIS cameras. Although the outburst
originated just outside the FOV of the instruments, the source region and the magnitude of the
outburst could be determined.
This document summarizes the discovery and characterization of Kepler-432 b, a massive exoplanet in a highly eccentric orbit around a red giant star. Key findings include:
1) Radial velocity measurements from the CAFE spectrograph revealed Kepler-432 b has a mass of 4.87 ± 0.48 MJup and moves in a highly eccentric orbit (e = 0.535 ± 0.030) around its host star.
2) Simultaneous modeling of Kepler photometry and radial velocity data determined Kepler-432 b has a radius of 1.120 ± 0.036 RJup and orbits every 52.5 days.
3) Analysis of high-resolution images found a nearby star
Pawan Kumar Relativistic jets in tidal disruption eventsBaurzhan Alzhanov
- Fast radio bursts (FRBs) are short, intense radio pulses that last about 1 millisecond. One FRB source produced multiple outbursts over several years.
- The leading model is that FRBs originate from young, highly magnetic neutron stars called magnetars. Charged particles are accelerated by magnetic reconnection, producing coherent curvature radiation observed as FRBs.
- FRBs provide insights into neutron star physics and energetic processes in magnetar magnetospheres. Predictions include observing FRB-like bursts at higher frequencies.
Uma equipe de astrofísicos usando o Observatório W. M. Keck no Havaí mediu com sucesso a galáxia mais distante já registrada e o mais interessante, capturou sua emissão de hidrogênio vista quando o universo tinha menos de 600 milhões de anos de vida. Adicionalmente, o método pelo qual a galáxia EGSY8p7 foi detectada dá uma ideia importante sobre como as primeiras estrelas no universo se acenderam depois do Big Bang.
Usando o poderoso espectrógrafo infravermelho do Observatório Keck, chamado MOSFIRE, a equipe datou a galáxia detectando sua linha de emissão Lyman-alpha – uma assinatura do gás hidrogênio quente, aquecido pela forte emissão ultravioleta de estrelas recém-nascidas. Embora, frequentemente seja possível detectar essa assinatura em galáxias próximas da Terra, a detecção da emissão Lyman-alpha nessas grandes distâncias é inesperada, já que ela é facilmente absorvida pelos numerosos átomos de hidrogênio que acredita-se existam no espaço entre as galáxias no nascer do universo. O resultado dá uma nova ideia sobre a reionização cósmica, o processo pelo qual nuvens escuras de hidrogênio foram partidas em seus prótons constituintes e elétrons pelas primeiras gerações de galáxias.
“Nós frequentemente observamos a linha de emissão Lyman-alpha do hidrogênio em objetos próximos já que eles são um dos traçadores mais confiáveis da formação de estrelas”, disse o astrônomo Adi Zitrin, do Instituto de Tecnologia da Califórnia, o Caltech, principal autor do estudo. “Contudo, à medida que penetramos mais fundo no universo, e então voltamos a tempos remotos, o espaço entre as galáxias continha um grande número de nuvens escuras de hidrogênio que absorviam esse sinal”.
The Internal Structure of Asteroid (25143) Itokawa as Revealed by Detection o...WellingtonRodrigues2014
- The authors detected an acceleration in the rotation rate of asteroid (25143) Itokawa through photometric observations spanning 2001 to 2013.
- By measuring rotational phase offsets between observed and modeled lightcurves, they found a YORP acceleration of 3.54 ± 0.38 × 10−8 rad day−2, equivalent to a decrease in the asteroid's rotation period of about 45 ms per year.
- Thermophysical modeling of the detailed shape model from the Hayabusa spacecraft could not reconcile the observed YORP strength unless the asteroid's center of mass is shifted by about 21 m along its long axis. This suggests Itokawa has two components with different densities that merged, either from a
This document contains a spelling list and sentences for students to practice words containing short vowel sounds. The 15-word spelling list includes common words like "part", "hard", "born", and "corn". There are also 5 short practice sentences using some of the words, such as questions about riding a horse, wanting more food, and sitting on a porch.
This spelling list for 5th period contains 15 words ending in -tion and -ture along with 5 sample sentences using some of the words. The words include mixture, nation, section, future, picture, fixture, motion, nature, feature, furniture, action, caution, station, adventure, and tuition. The sentences demonstrate the words being used in contexts like describing the first moon landing, allowing use of a book section, working at a fire station, enjoying sports with action, and replacing a light fixture.
This document contains a spelling list for 4th period with suffixes -ly, -ful, -er, and -or. It includes 15 words with those suffixes for students to study. It also provides 5 sample sentences using some of the spelling words, such as sentences about a visitor, a sailor, cheerful children, running quickly, and being a good helper.
The Army Museums Ogilby Trust is the only national organisation that represents, supports and promotes the regimental and corps museums of the British Army. As an independent private charity it relies entirely on its own resources and the generosity of others to fund its work.
The document contains charts analyzing the Toronto housing market from March 2014. It includes charts showing monthly MLS sales, new listings, sales-to-new listings ratios, average home prices for the current and previous three years. Additional charts show monthly sales, new listings and average prices trends over time from 1995 to present. The final chart shows the share of average household income used for mortgage payments, property taxes and utilities on an average priced GTA home.
Hitunglah dengan menggunakan koefisien binomialJack Code
Dokumen tersebut membahas tentang penghitungan koefisien binomial dan barisan bilangan dengan definisi rekursif menggunakan kondisi awal tertentu untuk menghitung nilai k. Diberikan instruksi untuk menghitung koefisien binomial, koefisien dalam ekspresi, nilai k untuk kondisi awal tertentu, serta nilai barisan bilangan berdasarkan definisi rekursifnya.
This document provides a spelling list and sentences for practice that focus on words containing common diphthongs such as "ch", "tch", "sh", "th", "wh". The list includes 15 words to practice spelling like "bunch", "that", "wish", and "math". It also includes 5 sentences using some of the words to practice reading comprehension, such as questions about identifying people, descriptions of animal size, and expressions of desires.
This document contains a list of spelling words containing long e sounds and sample sentences for students to practice. The spelling words list includes 14 words containing long e sounds represented by ee, ea, and y. It also includes 5 short sample sentences for students to practice spelling and reading the words in sentences.
El documento describe el agua, incluyendo que está compuesta de moléculas de H2O, cubre el 71% de la superficie terrestre y es esencial para la vida. El agua se encuentra principalmente en los océanos, glaciares, depósitos subterráneos y atmósfera. Circula constantemente a través del ciclo de evaporación, precipitación y desplazamiento hacia los mares. Aproximadamente el 70% del agua dulce se usa para agricultura, 20% para industria y 10% para uso dom
The document contains charts analyzing the Toronto housing market from July 2013. It includes charts showing monthly MLS sales, new listings, sales-to-new listings ratios, average home prices for the current and previous three years. Additional charts show monthly sales and new listings trends since 1995. A final chart analyzes housing affordability based on average household income and costs of an average priced home.
We help organizations increase profits, productivity, and employee satisfaction. As a business consulting firm, we provide strategies and solutions to optimize workplace culture and performance. Our goal is to help companies thrive by creating positive work environments where people and business can grow together.
El documento se define como cualquier objeto creado por el ser humano que proporciona información, independientemente de su forma física o el propósito para el que fue creado. Los documentos no solo incluyen escritos e impresos, sino también planos, fotos, cintas magnéticas, sellos, pinturas y más, siempre que contengan información registrada. Los documentos son instrumentos importantes para guiar y coordinar las actividades diarias de las entidades porque sustentan la toma de decisiones y documentan objetivamente la gestión.
El documento habla sobre diferentes tipos de cables y equipos de red. Menciona que el cable coaxial tiene menor probabilidad de interferencia y puede transmitir datos a largas distancias, mientras que el cable trenzado está compuesto de varios cables individuales. También describe las fibras ópticas, topologías físicas y lógicas, switches, routers, categorías de cables y equipos de conectividad pasivos y activos.
This document discusses the key roles, events, and artifacts of Scrum. Scrum is a framework for agile project management that focuses on iterative development with sprints, daily stand-ups, and reviews. The three main roles are the Product Owner who manages requirements, the Scrum Master who facilitates the process, and the cross-functional Team who does the work. Key events include Sprint Planning, Daily Scrum, Sprint Review, and Retrospective while artifacts include the Product Backlog, Sprint Backlog, and working software.
A closely packed system of low mass, low-density planets transiting kepler-11Sérgio Sacani
The document summarizes the discovery of six transiting exoplanets orbiting the star Kepler-11. Photometry from the Kepler spacecraft revealed periodic dips in the star's brightness consistent with multiple transiting planets. Six planetary candidates were identified, with orbital periods ranging from 10 to 47 days for the inner five planets. Radial velocity measurements confirmed the planetary nature of the five inner planets and allowed for mass estimates. The outermost sixth planet was also validated as a planet. Analysis of the transit times, durations and depths provided insights into the properties, dynamics, and stability of this unique six-planet system.
This document summarizes the discovery of two Earth-sized planets orbiting the star Kepler-20. Precise photometric data from the Kepler spacecraft revealed periodic transit signals indicating planets with sizes of 1.03 times (Kepler-20 e) and 0.87 times (Kepler-20 f) Earth's radius orbiting the star. Statistical analysis shows the planetary interpretation of the transit signals is over three orders of magnitude more likely than alternative hypotheses. The planets are likely rocky in composition.
Water vapour absorption in the clear atmosphere of a Neptune-sized exoplanetGOASA
1) The transmission spectrum of the exoplanet HAT-P-11b was observed using Hubble and Spitzer space telescopes.
2) Water vapor absorption was detected at 1.4 micrometers in the atmosphere, indicating a clear atmosphere down to 1 mbar pressure.
3) The detection of water vapor and relatively large atmospheric scale height places an upper limit on the abundance of heavy elements in the atmosphere of around 700 times the solar value, consistent with core accretion planet formation theories.
Water vapour absorption_in_the_clear_atmosphere_of_a_neptune_sized_exoplanetSérgio Sacani
This document summarizes research on the transmission spectrum of the exoplanet HAT-P-11b, a Neptune-sized planet. Observations from the Hubble Space Telescope and Spitzer Space Telescope detected water vapor absorption in the planet's atmosphere at a wavelength of 1.4 micrometers. Analysis of the spectrum indicates the atmosphere is predominantly clear down to 1 mbar and has a hydrogen abundance similar to solar values. Atmospheric modeling suggests a metallicity around 190 times that of the Sun's, in agreement with core accretion planet formation theories. This makes HAT-P-11b the smallest exoplanet to date with a detected molecular signature in its atmosphere, providing new insights into the composition and formation of Neptune-sized
A nearby m_star_with_three_transiting_super-earths_discovered_by_k2Sérgio Sacani
This document reports the discovery of three transiting super-Earth planets orbiting a nearby bright M0 dwarf star, EPIC 201367065, using data from the K2 mission. Photometry from K2 reveals three planetary candidates with orbital periods of 10.056, 24.641, and ~45 days and radii between 1.5-2.1 Earth radii. Spectroscopy of the host star determines it has a mass of 0.601 solar masses, radius of 0.561 solar radii, and is located about 45 parsecs away, making the planets some of the coolest small planets known around a nearby star. The system presents an opportunity to measure the planet masses and constrain atmospheric compositions via future observations
A rocky planet_transiting_a_nearby_low_mass_starSérgio Sacani
Um exoplaneta rochoso do tamanho da Terra, orbita uma estrela pequena e próxima, poderia ser o mundo mais importante já encontrado além do Sistema Solar, disseram os astrônomos.
O planeta localiza-se na constelação de Vela, no hemisfério sul do céu e é próximo o suficiente para que os telescópios possam observar qualquer atmosfera que ele possua, um procedimento que poderia ajudar a registrar algum tipo de vida, se ela existisse em outros planetas, no futuro.
Denominado de GJ 1132b, o exoplaneta é cerca de 16% maior que a Terra, e está localizado a cerca de 39 anos-luz de distância, o que faz com que ele seja três vezes mais próximo da Terra do que qualquer outro exoplaneta rochoso já descoberto. Nessa distância, espera-se que os telescópios sejam capazes de fazer uma análise química de sua atmosfera, a velocidade dos seus ventos e as cores do pôr-do-Sol, que acontecem no exoplaneta.
Os astrônomos registraram o planeta à medida que ele passava na frente da sua estrela, uma estrela do tipo anã vermelha, com somente um quinto do tamanho do Sol. Apesar de muito mais fria e muito mais apagada que o Sol, o GJ 1132b, tem uma órbita tão próxima da estrela que as suas temperaturas superficiais atingem cerca de 260 graus Celsius.
Essa temperatura, obviamente, é muito alta para reter a água em estado líquido na superfície do exoplaneta, fazendo com que ele seja inóspito para a vida, mas não tão quente para queimar toda uma atmosfera que pode ter se formado no planeta.
The transit method detects exoplanets by observing periodic dips in a star's light caused by planets passing in front of the star. This method has discovered over 80% of known exoplanets. It allows determining planet properties like radius, atmosphere composition by analyzing light passing through. The Kepler space telescope extensively uses this method to study exoplanet candidates.
Eccentricity from transit_photometry_small_planets_in_kepler_multi_planet_sys...Sérgio Sacani
Artigo descreve estudo que mostra que a órbita dos exoplanetas terrestres são na sua maioria órbitas circulares, o que é bom para se procurar por vida e o que vem causando uma revolução no entendimento sobre os sistemas de exoplanteas.
No signature of_ejecta_interaction_with_a_stellar_companion_in_three_type_ia_...Sérgio Sacani
ARtigo descreve estudos de supernovas feitos com o Kepler e mostram que explosões podem ser geradas por estrelas anãs brancas simples, se chocando com outras ou se fundindo com outras.
Kepler’s last planet discoveries: two new planets and one single-transit cand...Sérgio Sacani
The Kepler space telescope was responsible for the discovery of over 2700 confirmed exoplanets, more than half of the total
number of exoplanets known today. These discoveries took place during both Kepler’s primary mission, when it spent 4 yr
staring at the same part of the sky, and its extended K2 mission, when a mechanical failure forced it to observe different parts of
the sky along the ecliptic. At the very end of the mission, when Kepler was exhausting the last of its fuel reserves, it collected
a short set of observations known as K2 Campaign 19. So far, no planets have been discovered in this data set because it only
yielded about a week of high-quality data. Here, we report some of the last planet discoveries made by Kepler in the Campaign
19 dataset. We conducted a visual search of the week of high-quality Campaign 19 data and identified three possible planet
transits. Each planet candidate was originally identified with only one recorded transit, from which we were able to estimate
the planets’ radii and estimate the semimajor axes and orbital periods. Analysis of lower-quality data collected after low fuel
pressure caused the telescope’s pointing precision to suffer revealed additional transits for two of these candidates, allowing
us to statistically validate them as genuine exoplanets. We also tentatively confirm the transits of one planet with TESS. These
discoveries demonstrate Kepler’s exoplanet detection power, even when it was literally running on fumes.
Final Year Project - Observation and Characterisation of ExoplanetsLucy Stickland
This document summarizes a student report on the observation and characterization of exoplanets. It explores various exoplanet detection techniques, recent increases in Earth-sized planet discoveries, and relationships between stellar and planetary parameters. The student conducted photometry on three known transiting exoplanets - Hat-P-25b, Wasp-43b, and Wasp-2b - using the Sedgwick telescope. Light curves were produced and used to calculate planetary properties. A program called the Exoplanetary Pixelization Transit Model was created and tested to better fit light curves computationally.
The mass of_the_mars_sized_exoplanet_kepler_138_b_from_transit_timingSérgio Sacani
Artigo da revista Nature, descreve o trabalho de astrônomos para medir o tamanho e a massa de um exoplaneta parecido com Marte, além de caracterizar por completo o sistema planetário da estrela Kepler-138.
This document summarizes the discovery of Kepler-413b, a Neptune-sized circumbinary planet orbiting the eclipsing binary star system Kepler-413. The planet has an orbital period of approximately 66 days and an eccentric orbit with a semimajor axis of 0.355 AU. Analysis of the Kepler light curve revealed the planet's orbit is misaligned with the binary star plane by about 2.5 degrees, causing it to sometimes fail to transit one of the stars. The orbital configuration of the system places the planet interior to the habitable zone but its obliquity may undergo fluctuations on precession timescales.
This summarizes a scientific study on long-distance quantum teleportation between two laboratories separated by 55 meters but connected by 2 kilometers of fiber optic cable. The key points are:
1) Researchers teleported quantum states (qubits) carried by photons at 1.3 micrometer wavelengths onto photons at 1.55 micrometer wavelengths between the two laboratories.
2) The qubits were encoded in time-bin superpositions and entanglement rather than polarization to make them more robust against decoherence in optical fibers.
3) A partial Bell state measurement was performed using linear optics at the receiving end to probabilistically teleport the quantum states over the long distance.
The extremely high albedo of LTT 9779 b revealed by CHEOPSSérgio Sacani
Optical secondary eclipse measurements of small planets can provide a wealth of information about the reflective properties
of these worlds, but the measurements are particularly challenging to attain because of their relatively shallow depth. If such signals
can be detected and modeled, however, they can provide planetary albedos, thermal characteristics, and information on absorbers in
the upper atmosphere.
Aims. We aim to detect and characterize the optical secondary eclipse of the planet LTT 9779 b using the CHaracterising ExOPlanet
Satellite (CHEOPS) to measure the planetary albedo and search for the signature of atmospheric condensates.
Methods. We observed ten secondary eclipses of the planet with CHEOPS. We carefully analyzed and detrended the light curves using
three independent methods to perform the final astrophysical detrending and eclipse model fitting of the individual and combined light
curves.
Results. Each of our analysis methods yielded statistically similar results, providing a robust detection of the eclipse of LTT 9779 b
with a depth of 115±24 ppm. This surprisingly large depth provides a geometric albedo for the planet of 0.80+0.10
−0.17, consistent with
estimates of radiative-convective models. This value is similar to that of Venus in our own Solar System. When combining the eclipse
from CHEOPS with the measurements from TESS and Spitzer, our global climate models indicate that LTT 9779 b likely has a super
metal-rich atmosphere, with a lower limit of 400× solar being found, and the presence of silicate clouds. The observations also reveal
hints of optical eclipse depth variability, but these have yet to be confirmed.
Conclusions. The results found here in the optical when combined with those in the near-infrared provide the first steps toward
understanding the atmospheric structure and physical processes of ultrahot Neptune worlds that inhabit the Neptune desert.
- Astrônomos descobriram que uma pequena estrela, do tamanho de Júpiter, possui uma tempestade muito parecida com a Grande Mancha Vermelha e que está ali, persistente por dois anos.
- Enquanto nos planetas, esse tipo de característica é normal, em estrelas essa é a melhor evidência encontrada até hoje.
- A estrela é chamada de W1906+40 e pertence a uma classe de objetos frios chamados de Anãs-L.
- Elas são consideradas estrelas pois fundem átomos e geram luz, como o Sol faz, enquanto que as anãs marrons são conhecidas como estrelas que falharam, pois elas não possuem o processo de fusão atômica em seu interior.
- Nesse novo estudo os astrônomos foram capazes de verificar as mudanças na atmosfera da estrela por dois anos. A técnica usada foi semelhante à de detecção de exoplanetas, analisando a curva de luz da estrela, que apresentava quedas, mas que não era por questão de planetas.
- Os astrônomos usaram o Spitzer e estudaram a luz infravermelha da estrela, que revelou uma gigantesca mancha escura que não era uma mancha magnética estelar, mas sim uma tempestade com um diâmetro equivalente ao de 3 Terras. O spitzer foi capaz de estudar camadas diferentes da atmosfera da estrela e esses dados junto com os dados do Kepler, revelaram com clareza a tempestade estelar.
- Futuras observações serão realizadas usando os dois equipamentos para tentar identificar esse tipo de tempestade em anãs marrons, por exemplo, e tentar descobrir se esse tipo de fenômeno é muito comum, ou é raro no universo.
A super earth_sized_planet_orbiting_in_or_near_the_habitable_zone_around_sun_...Sérgio Sacani
This document summarizes the discovery of a super-Earth-sized planet orbiting in or near the habitable zone of a Sun-like star called Kepler-69. Using data from the Kepler spacecraft, astronomers detected two planets transiting Kepler-69, called Kepler-69b and Kepler-69c. Kepler-69c is estimated to have a radius of 1.7 Earth radii and orbit every 242.5 days, placing it close to the star's habitable zone where liquid water could exist on the surface. At 1.7 Earth radii, Kepler-69c represents the smallest planet found by Kepler to be potentially habitable, and is an important discovery on the path to finding the first true Earth analog.
IOSR Journal of Applied Physics (IOSR-JAP) is an open access international journal that provides rapid publication (within a month) of articles in all areas of physics and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in applied physics. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
Astronomy from the Moon: From Exoplanets to Cosmology and Beyond in Visible L...Sérgio Sacani
We review what could be astronomy from the Moon in the next decades in the visible domain.
After a short review observational approaches, from photometry to high contrast and high angular
resolution imaging, We essentially focus on some promising scientific objectives, from Solar
System to the extragalactic domain. At the end, I add a proposal to use the Earth-Moon system to
test fundamental physics. Since this meeting is dedicated to the next decades of Astronomy from
the Moon, we consider projects and science objectives for several decades from now.
Astronomy from the Moon: From Exoplanets to Cosmology and Beyond in Visible L...
Transiting Exoplanets
1. Transiting Exoplanets
Ian Beagles and Eli Todd 16APR2014
Department of Physics and Astronomy, Northern Arizona University, Flagstaff, Arizona 86001
Abstract
The Kepler-9 system holds great scientific value as the first multi-planetary system found using
the photometric transit method. The transit time variations (TTVs) for Kepler-9’s planets are the first to
have been found in another system. Using transit data and radial velocity data from Holman et al.
(2010), we found the radius, period, TTV, semi-major axis, mass, and density for Kepler-9b, Kepler-9c,
and where possible, Kepler-9d. We found that Kepler-9b and 9c are Saturn-sized planets with 19.24 and
39.08 day periods respectively and Kepler-9d is a super-Earth-sized planet with a period of 1.59 days.
1. Introduction
The Kepler mission is designed to survey a section of the Milky Way Galaxy to discover the
frequency of Earth-size planets orbiting in the habitable zone of stars. Kepler is able to detect exoplanets
by observing the dimming of a star’s light when a planet passes in front of its host star. Several traits of
the planet can be calculated from the characteristics of the dip in the star’s light. The planet’s orbital
period can be determined by the frequency of the planet’s transits and the planet’s size is ascertained
by the transit depth. Other system and planetary properties are suggested by or refined from using data
from transit information. Multiple planets in the system are suggested by variations in a planet’s transit
duration. Because of the nature of detecting planetary transits, the planet’s inclination is limited to the
size of its star. This limit on inclination allows the mass and density of the planet to be calculated to a
high degree of accuracy when combined with radial velocity data.
Doppler spectroscopy, also known as the radial velocity method, uses the Doppler shifts in the
spectrum of a star to detect exoplanets. Using the radial velocity method, a minimum mass for the
planet orbiting the star can be determined from the spectral shifts caused by the planet. The actual
mass for the planet cannot be calculated from the radial velocity method without knowing the planet’s
inclination with respect to us. The planet’s inclination can be found if spectral lines for the planet can be
separated from the star’s spectral lines. Finding the inclination for the planets in a system where the
planets transit is much easier since the inclination is limited by the size of the star.
To date, Kepler has found over 900 confirmed exoplanets with ~4,000 other planetary
candidates (NASA 2013). The Kepler-9 system was first detected by Kepler in 2010 and was the first
multi-planetary system to be discovered using the transit method. Two gas giants and a super-Earth
have all been detected orbiting Kepler-9. The Kepler-9 system is of great interest as it is the first
extrasolar system whose planetary transit time variations (TTVs) have been obtained.
2. Data
The data provided to us contained data from the Kepler mission’s observations of the Kepler-9
system. This data was refined by Holman et al. in their 2010 article (hereafter H2010) to indicate which
data points correlated to the noise of Kepler-9 and which to the transits of Kepler-9’s planets. We then
used the flags provided by Holman et al. to color code the data provided by H2010 in order to easily
identify the transits of Kepler-9’s planets (Fig. 1). As of 2010 the existence of Kepler-9d was only posited
2. via TTVs in Kepler-9b and 9d by Holman & Murray in their 2005 article (hereafter H2005), and as can be
seen in Fig. 1 the transits of Kepler-9d lie almost entirely within the noise of Kepler-9. The existence of
Kepler-9d was later confirmed by Torres et al. in 2011 (hereafter T2011) via extensive computer
modeling and data analysis.
Using the data provided by H2010, we were able to determine: the periods of Kepler-9’s
planets, the TTVs for Kepler-9b and 9c, the semi-major axes of the planets, their radii, and using
photometric data, the mass and density of 9c and, the mass and density of both 9b and 9c using radial
velocity data provided in Holman et al. Supplementary Online Material 2010 (hereafter SOM).
Orbital Periods:
Using the transit flags from the data of H2010 we used MatLab separate out the transits of
Kepler-9b (Fig. 2), 9c (Fig. 4) and 9d (Fig. 6) and to then determine the mean periods of each planet
(Table 1), along with the standard deviation in those values. For 9b and 9c we used the lowest value of
the flagged data in each transit as the midpoint of each transit. For 9d we used the flagged data in the
range of BJD 78.5098-94.3872. This period lies in the first quarter of observation and within the first and
50 100 150 200 250 300
0.993
0.994
0.995
0.996
0.997
0.998
0.999
1
1.001
1.002
1.003
Days from BJD 2454900 (Days)
DetrendedKepler-9Flux(W/m2
)
Detrended Light Curve of Kepler-9 Data
Detrended Flux
Planet B
Planet C
Planet D
Planets B&D
Planets C&D
Figure 1: The detrended light curve data of the Kepler-9 system, color coded by the noise of Kepler-9 and the transits of its
planets. It can be seen that the transits of 9d (the red dots) lie almost entirely in the noise of Kepler-9. The discontinuities in
the data correspond to the breaks in the quarters, when Kepler-9 moves to a different detector after the rotation of the
Kepler spacecraft.
3. second orbits of 9b. We chose this range in order to minimize potential perturbations by 9b and error
from renormalization of data after the quarterly change to a different detector on the Kepler spacecraft
(H2010).
Kepler-9 Planetary Periods Period (Days) Error (days)
Planet 9b 19.2414 ±0.0263
Planet 9c 39.0816 ±0.0913
Planet 9d 1.5877 ±0.0610
Table 1: The mean orbital periods (in days) of the Kepler-9 planets as calculated using the H2010 data and MatLab. These
results lie within error tolerances of the values published in H2010.
While we chose the lowest valued points of the data flagged as transits for 9d within our range, as can
be seen (Fig. 7), these flagged transits do not possess the same symmetry as the flagged transits of
planets 9b (Fig. 3) and 9c (Fig. 5). The values that we calculated for these periods and their attendant
error have them straddle the values and error that were published in H2010 and for 9d, T2011.
Figure 2: The detrended light curve data of Kepler-9, filtered for the transits of planet 9b (the blue and magenta dots) and the
noise of Kepler-9 (the black dots). As can be seen, the third and seventh transits of 9b are missing. This is due to the quarterly
rotation of the Kepler spacecraft.
4. 134.75 134.8 134.85 134.9 134.95 135 135.05 135.1 135.15 135.2
0.993
0.994
0.995
0.996
0.997
0.998
0.999
1
1.001
Days from BJD 2454900 (Days)
DetrendedKepler-9Flux(W/m2
)
Detrended Light Curve of Kepler-9b Data
Detrended Flux
Planet B
Planet B&D
Figure 3: A magnified image of the fourth transit of Kepler-9b, with the vertical scale held constant. This view shows the
expected symmetrical nature of the dip in luminosity as 9b transits Kepler-9.
50 100 150 200 250 300
0.993
0.994
0.995
0.996
0.997
0.998
0.999
1
1.001
Days from BJD 2454900 (Days)
DetrendedKepler-9Flux(W/m2
)
Detrended Light Curve of Kepler-9c Data
Detrended Flux
Planet C
Planet C&D
Figure 4: The detrended light curve data of Kepler-9, filtered for the transits of planet 9c (the green dots) and the noise
of Kepler-9 (the black dots). Here, all of the transits of 9c can be seen, as they did not coincide with the quarterly
rotation of the Kepler spacecraft.
5. 263.8 263.9 264 264.1 264.2 264.3 264.4 264.5 264.6 264.7
0.993
0.994
0.995
0.996
0.997
0.998
0.999
1
1.001
Days from BJD 2454900 (Days)
DetrendedKepler-9Flux(W/m2
) Detrended Light Curve of Kepler-9c Data
Detrended Flux
Planet C
Planet C&D
Figure 5: A magnified image of the sixth transit of Kepler-9c, with the vertical scale held constant. This view shows the expected
symmetry in the nature of the dip in luminosity as 9c transits Kepler-9.
50 100 150 200 250 300
0.997
0.998
0.999
1
1.001
1.002
1.003
Days from BJD 2454900 (Days)
DetrendedKepler-9Flux(W/m2
)
Detrended Light Curve of Kepler-9d Data
Detrended Flux
Planet D
Figure 6: The detrended light curve data of Kepler-9, filtered for the transits of planet 9d (the red dots) and the noise of
Kepler-9 (the black dots). Here, it can be seen that the data flagged as transits of 9d lie almost completely within the noise of
Kepler-9.
6. Planetary Radii:
Using the periods that we had calculated and equation 1, we then calculated the radii of planets
9b, 9c and 9d (Table 2) using our code in MatLab.
𝑅 𝑝 = 𝑅∗√∆𝐹𝑙𝑢𝑥 (1).
Here; Rp is the radius of the plant in question, R∗ is the radius of Kepler-9, which was given to be 1.1Rʘ
and ΔFlux is the mean value of the flux when there is no transit i.e. 1 minus the flux at the mid-point of
the transit all divided by the mean value of the flux when there is no transit, again, 1 (Seager and
Mallen-Ornelas 2003).
The values that we calculated, along with the standard deviation in those calculations put them
on either side of the range of values published in H2010 and in the case of 9d, T2011.
75 76 77 78 79 80 81 82
0.997
0.998
0.999
1
1.001
1.002
1.003
Days from BJD 2454900 (Days)
DetrendedKepler-9Flux(W/m2
)
Detrended Light Curve of Kepler-9d Data
Detrended Flux
Planet D
Figure 7: A magnified image of the transits of Kepler-9d from BJD 75 - 82, with the vertical scale held constant. This plot
displays that the data flagged as 9d transits do not exhibit the characteristic symmetry in the luminosity dip that is found in
the transit data for planets 9b and 9c.
7. Kepler-9
Planetary Radii
Radius in Solar
Radii (Rp/Rʘ)
Error in Radius
(Rʘ)
Radius in
Jupiter Radii
(Rp/RJ)
Error in Radius
(RJ)
Planet 9b 0.0904 0.0011 0.8794 0.0103
Planet 9c 0.0875 0.0013 0.8515 0.0122
Planet 9d 0.0253 0.0046 0.2466 0.0444
Table 2: The mean Radii of Planets 9b, 9c and 9d in both solar radii and Jupiter Radii, along with the standard deviation in
those calculations. These values are within the error tolerance of the values published in H2010.
TTV:
Having calculated the average period of each planet in Kepler-9, we then plotted the predicted
mid-point of the transits (in BJD) along with the observed mid-points of the transits (in BJD) of 9b and 9c
(Figs. 8 and 11 respectively). We then used MatLab to find the best fit for the TTVs of 9b and 9c (Table
3). The error in the TTV calculations is large, but the values that we calculated for TTV of 9b and 9c still
encompass the values published in H2010.
Transit Time Variances TTV (Days) Error (Days)
Planet 9b -0.0127 ±0.0196
Planet 9c +0.0444 ±0.101
Table 3: The TTV values that we derived using the Kepler-9 data. Though the standard deviation in the TTVs is large, our
values are still consistent with those published in H2010.
Figure 8: A plot of the predicted and observed midpoints of the transits for Kepler-9b. The actual transits (black dots) are off-
set from the predicted Transits (red dots) for clarity.
50 100 150 200 250 300
0.9
1
1.1
1.2
1.3
1.4
1.5
Days from BJD 2454900 (Days)
Off-SetofY-AxisforVisibilityofDataPoints
Actual Transits vs. Predicted Transits for Kepler-9b
Actual Transits (black)
Predicted Transits (red)
8. Figure 9: A zoomed-in view of the last transit of 9c. This view of the predicted and actual midpoints of the transits, better
display the TTV as a function of time.
Figure 10: A plot of the predicted and observed midpoints of the transits for Kepler-9c. The actual transits (black dots) are
off-set from the predicted Transits (red dots) for clarity.
153.8 153.9 154 154.1 154.2 154.3 154.4 154.5 154.6
0.9
1
1.1
1.2
1.3
1.4
1.5
Days from BJD 2454900 (Days)
Off-SetofY-AxisforVisibilityofDataPoints
Actual Transits vs. Predicted Transits for Kepler-9b
Actual Transits (black)
Predicted Transits (red)
50 100 150 200 250 300
0.9
1
1.1
1.2
1.3
1.4
1.5
Days from BJD 2454900 (Days)
Off-SetofY-AxisforVisibilityofDataPoints
Actual Transits vs. Predicted Transits for Kepler-9c
Actual Transits (black)
Predicted Transits (red)
9. Figure 11: A zoomed-in view of the last transit of 9c. This view of the predicted and actual midpoints of the transits, better
display the TTV as a function of time.
Semi-major Axes:
Once we had calculated the values for planetary periods, radii, and TTV. We were then able to
calculate the semi-major-axes of the planets in the Kepler-9 system (Table 4) using the non-Newtonian
form of Kepler’s Third Law (Eqn. 2) and MatLab.
𝑎 𝑝 = √ 𝑃𝑝
2 ∗ 𝑀∗
3
(2).
Here; ap is the semi-major axis of the planet in question (in AU), Pp is the period of the planet in question
(in earth years) and M∗is the mass of the star that the planet in question orbits, in our case the mass of
Kepler-9 is taken to be one solar mass.
Kepler-9 Planetary Semi-
Major Axes
Semi-Major Axis: a
(AU)
Error
(AU)
Planet 9b 0.1405 ±0.0263
Planet 9c 0.2251 ±0.0913
Planet 9d 0.0266 ±0.0610
Table 4: The values that we calculated for the semi-major axes of Kepler-9b, 9c and 9d, along with their attendant error
tolerances. These values are within the error tolerances of the values published in H2010 and T2011.
The values that we obtained for the semi-major axes of planets Kepler-9b, 9c and 9d, when taking into
account their standard deviations, agreed with those values published in H2010 and T2011.
262.5 263 263.5 264 264.5 265 265.5 266
0.9
1
1.1
1.2
1.3
1.4
1.5
Days from BJD 2454900 (Days)
Off-SetofY-AxisforVisibilityofDataPoints
Actual Transits vs. Predicted Transits for Kepler-9c
Actual Transits (black)
Predicted Transits (red)
10. Calculation of Mass from Photometric Data:
Using the previously derived data and equation 3 (H2005), we were then able to calculate the
mass of Kepler-9c (Table 5) using the eccentricities of 9b and 9c as found in SOM. We then calculated
the density of 9c as mass per unit volume (g/cm3
) (Table 5).
𝑀 𝑐
𝑀∗
=
𝑇𝑇𝑉 𝑏[1−√2(
𝑎 𝑏
𝑎 𝑐−(1−𝑒 𝑐)
)
3
2
]2
45𝜋∗𝑃 𝑏[
𝑎 𝑏
𝑎 𝑐−(1−𝑒 𝑐)
]3
(3).
Here; Mc is the mass of Kepler-9c, 𝑀∗ is the mass of Kepler-9 (taken to be 1 solar mass), TTVb is the
transit time variation for 9b, ab is the semi-major axis of 9b, ac is the semi-major axis of 9c, Pb is the
period of 9b, and ec is the eccentricity of 9c’c orbit. All of these values were converted into SI units.
Photometric
Calculation of
Kepler-9c’s Mass
and Density
Mass
(kg)
Mass in
Solar
Masses
(MC/ Mʘ)
Error in
Solar Mass
(Mʘ)
Density
(g/cm3)
Error in
Density
(g/cm3)
Planet 9c 7.4477*1024
0.0039 ±0.0951 0.0078814 0.0008738
Table 5: The mass of Kepler-9c as calculated using the photometric data of the Kepler spacecraft. This value is not close to
the values that were published in H2010, but that is to be expected, as the error in out TTVs was large and this method of
mass derivation is known to be inaccurate.
Our values for the mass of Kepler-9c, in solar masses, and its density were off by 2 orders of magnitude.
This can be accounted for by the compounding of all of the experimental uncertainties contained in all
of the previous calculations used to obtain the values used for these calculations. This is one of the
reasons why calculating mass from photometric data is known to be wildly inaccurate.
Calculation of Masses from Radial Velocity Data:
Lastly, we used radial velocity data provided in SOM to determine the half-amplitude of the
radial velocity curve: K (Table 6), and equation 4 to recalculate the mass and density for Kepler-9c as
well as the mass and density of Kepler-9b (Table 7).
𝑀 𝑝 = 𝑣𝑟,∗√
𝑀∗ 𝑎 𝑝
𝐺
(4).
Here; Mp is the mass of the planet in question, vr,* is the radial velocity of Kepler-9, M∗ is the mass of
Kepler-9 (taken to be one solar mass), ap is the semi-major axis of the planet in question, and G is the
universal constant.
Half-amplitude of Kepler-9
Radial Velocity Curve (K)
K of Kepler-9 Planet
(m/s)
Error
(m/s)
Planet 9b 21.4200 ±0.0849
Planet 9c 12.5200 ±0.1067
Table 6: The values of K (the half-amplitude of the radial velocity curve) calculated from data in SOM, along with their errors.
11. We needed to calculate K in order to get the radial velocity of Kepler-9. As K = v∗sin(i), where i is
the inclination of the orbital plane of the planet with respect to the line of sight of the observer, and as
we take the value of sin(i) to approach unity then we can approximate K = v∗, where v∗ is the orbital
velocity of Kepler-9. We can also approximate the orbital velocity of Kepler-9 as the radial velocity of
Kepler-9 at these distances, hencevr,∗ = v∗.
Mass and
Density of
Kepler-9
Planets
Mass of
Planet
(kg)
Mass in
Jupiter
Masses
(Mp/MJ)
Error in
Jupiter Mass
(MJ)
Density of
Planets
(g/cm3)
Error in
Density
(g/cm3)
Planet 9b 5.3618*1026
0.2824 0.0888 0.5150 ±.0011
Planet 9c 3.9668*1026
0.2089 0.1400 0.4197 ±.0013
Table 7: The recalculated values of the masses and densities of Kepler-9b and 9c. These values agree very closely with the
values published in H2010.
The values that we obtained via this method agree with the published values (H2010) to within the error
tolerances.
3. Discussion of Results
From our results we were able to see that the ratio of the period of Kepler-9c’s period to 9b’s
period was 2.0279. This indicates that 9c and 9b are in a 2:1 mean motion resonance (MMR), this finding
agrees also with the findings of H2010. Due to the fact that Kepler-9d was not confirmed until 2011 by
T2011, and that the data points for the transits of 9d reside in the noise of Kepler-9 in H2010’s data the
period of 9d has a large error relative to its magnitude. This error, though comparatively large, still
places our calculations in agreement with the values in H2010.
Our ranges for the values of the periods of the planets “bracket” H2010’s values. This holds true
for our values of semi-major axes, planetary radii, planetary masses, and densities as well, though this
only holds for the masses and densities derived through the radial velocity method. As can be seen,
(Table 5) the value for the mass and hence the value for the density of Kepler-9c, as derived via the
Photometric data are nowhere near the published values. These values are off by a factor of two orders
of magnitude. This only confirms that this method of mass calculation is an inaccurate one. These
inaccuracies arise from compounded experimental uncertainties contained within all of the previous
calculations used to derive each successive value.
Fortunately the radial velocity method of computing mass, and hence density, is a much more
accurate method. Our values for the masses and densities of 9b and 9c (Table 7) agree very closely with
those published in H2010.
From the values that we derived (Table 2) for the planetary radii, we were able to conclude that
both Kepler-9b and 9c were Saturn-sized planets while 9d is a super-Earth-sized planet. Also (Table 4)
that they all orbit very close to Kepler-9 relative to Earth’s orbit, much less Jupiter’s.
The error ranges are very high with respect to the magnitudes of the values (Table 3) of the TTVs
for 9b and 9c. While we used the same methods as we used to find the TTVs for both 9b and 9c on 9d,
the resulting numbers were not valid data. The error was significantly larger than the value of the
calculated TTV for 9d. This is mainly due to the transits of 9d being obscured by the noise of Kepler-9.
12. 5. Conclusion
The values we calculated for the Kepler-9 system agreed with the published values in H2010 and
T2011. We were limited to using the provided data and equations instead of using H2010’s more
complex and sophisticated modeling techniques. Our method of calculating values for the Kepler-9
system resulted in larger errors than the published results. Kepler-9b and Kepler-9c were determined to
be Saturn-sized planets in a 2:1 MMR orbiting close to their parent star. Through our methods, only the
period, semi-major axis, and radius of Kepler-9d could be calculated since much of the data for Kepler-
9d was obscured by the noise from the rest of the Kepler-9 system. We found that Kepler-9d is a super-
Earth orbiting very close to its star which agrees with the conclusions published in T2011.
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