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This document contains a 15-question pre-assessment for an introductory modern astronomy course. The questions cover topics ranging from the order of objects in the solar system by distance from Earth, to the properties of star spectra, to Kepler's laws of planetary motion, to the formation of the solar system and properties of planets such as Venus, Neptune, and the Moon. The assessment is designed to gauge students' existing knowledge on fundamental astronomy concepts before beginning the course.
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761-3134-1-PB
This paper considers the plausibility of time dilation effects shown in the film Interstellar. It calculates that for an hour to pass on a planet orbiting a 100 million solar mass black hole while 7 years pass on Earth, the planet would need to orbit at 2.95 astronomical units from the black hole. However, this distance is inside the minimum stable orbit, so the planet would not be able to maintain that orbit around a non-rotating black hole. A rotating black hole could allow for a stable orbit at that distance. The paper also finds that travel times depicted in the film between the planet and a safe orbit are implausibly short.
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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.
opgave
1) A carbon atmosphere has been discovered on the neutron star located at the center of the Cassiopeia A supernova remnant. This resolves a mystery about the nature of this object and provides evidence of the extreme environments around neutron stars.
2) The carbon atmosphere is only about 10 cm thick but has a density similar to diamond and a pressure over 10 times that at Earth's core. Its high temperature of almost 2 million degrees is balanced by the neutron star's intense surface gravity, 100 billion times stronger than Earth's, resulting in an incredibly thin atmosphere.
3) Given the neutron star's radius of 14 km, calculate the total mass of the carbon atmosphere.
Hubble Info w/ Pictures
The Hubble Space Telescope is a robotic telescope located 593 km above Earth's surface. It was launched in 1990 as a joint NASA and ESA project, inaugurating the Great Observatories program. Hubble weighs 11 tons, is 13.2 m long and has a maximum diameter of 4.2 meters. It can obtain higher resolution images than ground-based telescopes.
A 2 4_determination_of_the_local_value_of_the_hubble_constant
We use the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST) to
reduce the uncertainty in the local value of the Hubble constant from 3.3% to 2.4%.
The bulk of this improvement comes from new, near-infrared observations of Cepheid
variables in 11 host galaxies of recent type Ia supernovae (SNe Ia), more than doubling
the sample of reliable SNe Ia having a Cepheid-calibrated distance to a total of 19; these
in turn leverage the magnitude-redshift relation based on 300 SNe Ia at z <0.15. All
19 hosts as well as the megamaser system NGC4258 have been observed with WFC3
in the optical and near-infrared, thus nullifying cross-instrument zeropoint errors in the
relative distance estimates from Cepheids. Other noteworthy improvements include a
33% reduction in the systematic uncertainty in the maser distance to NGC4258, a larger
sample of Cepheids in the Large Magellanic Cloud (LMC), a more robust distance to
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Cepheids in M31, and new HST-based trigonometric parallaxes for Milky Way (MW)
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12 3-2014 atsoa.ppt
Hello guys, this ppt contains my project work on photometric analysis of Supernova 2008gj..with collaborators Ms. Komal Kabara and Manikandan K........Take a look.......looking forward for your suggestions...
The Internal Structure of Asteroid (25143) Itokawa as Revealed by Detection o...
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 aMagnetic interaction of_a_super_cme_with_the_earths_magnetosphere_scenario_fo...
Solar eruptions, known as Coronal Mass Ejections (CMEs), are
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on G-type stars have implied that so called super-CMEs, possessing kinetic
energies 10 times of the most powerful CME event ever observed on the Sun,
could be produced with a frequency of 1 event per 800-2000 yr on solar-
like slowly rotating stars. We have performed a 3D time-dependent global
magnetohydrodynamic simulation of the magnetic interaction of such a CME
cloud with the Earth's magnetosphere. We calculated the global structure
of the perturbed magnetosphere and derive the latitude of the open-closed
magnetic eld boundary. We also estimated energy
uxes penetrating the
Earth's ionosphere and discuss the consequences of energetic particle
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761-3134-1-PB
This paper considers the plausibility of time dilation effects shown in the film Interstellar. It calculates that for an hour to pass on a planet orbiting a 100 million solar mass black hole while 7 years pass on Earth, the planet would need to orbit at 2.95 astronomical units from the black hole. However, this distance is inside the minimum stable orbit, so the planet would not be able to maintain that orbit around a non-rotating black hole. A rotating black hole could allow for a stable orbit at that distance. The paper also finds that travel times depicted in the film between the planet and a safe orbit are implausibly short.
The canarias einstein_ring_a_newly_discovered_optical_einstein_ring
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.
opgave
1) A carbon atmosphere has been discovered on the neutron star located at the center of the Cassiopeia A supernova remnant. This resolves a mystery about the nature of this object and provides evidence of the extreme environments around neutron stars.
2) The carbon atmosphere is only about 10 cm thick but has a density similar to diamond and a pressure over 10 times that at Earth's core. Its high temperature of almost 2 million degrees is balanced by the neutron star's intense surface gravity, 100 billion times stronger than Earth's, resulting in an incredibly thin atmosphere.
3) Given the neutron star's radius of 14 km, calculate the total mass of the carbon atmosphere.
Hubble Info w/ Pictures
The Hubble Space Telescope is a robotic telescope located 593 km above Earth's surface. It was launched in 1990 as a joint NASA and ESA project, inaugurating the Great Observatories program. Hubble weighs 11 tons, is 13.2 m long and has a maximum diameter of 4.2 meters. It can obtain higher resolution images than ground-based telescopes.
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We use the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST) to
reduce the uncertainty in the local value of the Hubble constant from 3.3% to 2.4%.
The bulk of this improvement comes from new, near-infrared observations of Cepheid
variables in 11 host galaxies of recent type Ia supernovae (SNe Ia), more than doubling
the sample of reliable SNe Ia having a Cepheid-calibrated distance to a total of 19; these
in turn leverage the magnitude-redshift relation based on 300 SNe Ia at z <0.15. All
19 hosts as well as the megamaser system NGC4258 have been observed with WFC3
in the optical and near-infrared, thus nullifying cross-instrument zeropoint errors in the
relative distance estimates from Cepheids. Other noteworthy improvements include a
33% reduction in the systematic uncertainty in the maser distance to NGC4258, a larger
sample of Cepheids in the Large Magellanic Cloud (LMC), a more robust distance to
the LMC based on late-type detached eclipsing binaries (DEBs), HST observations of
Cepheids in M31, and new HST-based trigonometric parallaxes for Milky Way (MW)
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12 3-2014 atsoa.ppt
Hello guys, this ppt contains my project work on photometric analysis of Supernova 2008gj..with collaborators Ms. Komal Kabara and Manikandan K........Take a look.......looking forward for your suggestions...
The Internal Structure of Asteroid (25143) Itokawa as Revealed by Detection o...
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- 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.
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Solar eruptions, known as Coronal Mass Ejections (CMEs), are
frequently observed on our Sun. Recent Kepler observations of super
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on G-type stars have implied that so called super-CMEs, possessing kinetic
energies 10 times of the most powerful CME event ever observed on the Sun,
could be produced with a frequency of 1 event per 800-2000 yr on solar-
like slowly rotating stars. We have performed a 3D time-dependent global
magnetohydrodynamic simulation of the magnetic interaction of such a CME
cloud with the Earth's magnetosphere. We calculated the global structure
of the perturbed magnetosphere and derive the latitude of the open-closed
magnetic eld boundary. We also estimated energy
uxes penetrating the
Earth's ionosphere and discuss the consequences of energetic particle
uxes
on biological systems on early Earth.
Low surface brightness_imaging_of_the_magellanic_system_imprints_of_tidal_int...
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.
Math Project
This document summarizes the steps taken to calculate the intersection point and speed of North Korean and American missiles hypothetically launched at the moon. It shows the work done to find that the missiles would intersect at approximately 10.4 days and 232,376.7 miles from Earth. It then calculates the speeds of each missile in miles per hour and kilometers per hour. It concludes that the American missile was able to intercept and destroy the North Korean missile in time to save the moon.
Math Project
This document summarizes the steps taken to calculate the intersection point and speed of North Korean and American missiles hypothetically racing to destroy the moon. It is determined that the American missile would intercept the North Korean missile at around 10.4 days and 232,376 miles from Earth, just in time to save the moon based on its average distance from Earth of 233,818 miles. However, it is noted that errors could occur due to rounding and because the moon's distance varies in its elliptical orbit.
Hubble
The Hubble Space Telescope is a robotic telescope located 593 km above Earth's surface. Named after Edwin Hubble, it was launched in 1990 as a joint NASA and ESA project. Hubble can obtain higher resolution images at 0.1 seconds of arc. The document then provides 10 examples of Hubble's best photos, which include galaxies, nebulae, and other celestial objects located between 2.5 to 114 million light years from Earth. Additional photos from Hubble are also presented showing various planets, moons, stars, and other astronomical phenomena in our solar system and beyond. The last photo shown is the Eagle Nebula, located in the constellation Serpens, which features young stars forming within gaseous emissions.
Hubble
The Hubble Space Telescope is a robotic telescope located 593 km above Earth's surface. Named after Edwin Hubble, it was launched in 1990 as a joint NASA and ESA project. Hubble weighs 11 tons and can obtain images with a resolution of 0.1 seconds of arc. The document then provides 10 examples of Hubble's best photographs, which include galaxies, nebulae, and other celestial objects located between 2.5 to 114 million light years from Earth. It concludes by showing an image of the Eagle Nebula, where young stars are forming within gaseous emissions.
Hubble
The Hubble Space Telescope is a robotic telescope located 593 km above Earth's surface. Named after Edwin Hubble, it was launched in 1990 as a joint NASA and ESA project. Hubble weighs 11 tons and can obtain images with a resolution of 0.1 seconds of arc. Some of Hubble's most famous images include the Galaxy Hat, the Eskimo Nebula, and the Hourglass Nebula. Other images show planets in our solar system, nebulae, galaxies, and more distant objects in space.
Hubble
The Hubble Space Telescope is a robotic telescope located 593 km above Earth's surface. Named after Edwin Hubble, it was launched in 1990 as a joint NASA and ESA project. Hubble weighs 11 tons and can obtain images with a resolution of 0.1 seconds of arc. The document then provides 10 examples of Hubble's best photographs, which include galaxies, nebulae, and other celestial objects located between 2.5 to 114 million light years from Earth. It concludes by showing an image of the Eagle Nebula, where young stars are forming within gaseous emissions.
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This document discusses ultra-compact binary star systems that emit gravitational waves (GWs) due to their short orbital periods and high masses. It provides an overview of GWs based on Einstein's theory of general relativity, which predicts that massive, accelerating objects will produce ripples in spacetime. The proposed LISA mission aims to directly detect these GWs using a triangle-shaped array of satellites that will measure fluctuations in spacetime caused by passing GWs. Data is presented on 10 known ultra-compact binary systems in the Milky Way, showing their properties allow for calculations of expected GW strain, orbital decay rates, coalescence times, and luminosities.
Exocometary gas in_th_hd_181327_debris_ring
An increasing number of observations have shown that gaseous debris discs are not an
exception. However, until now we only knew of cases around A stars. Here we present the first
detection of 12CO (2-1) disc emission around an F star, HD 181327, obtained with ALMA
observations at 1.3 mm. The continuum and CO emission are resolved into an axisymmetric
disc with ring-like morphology. Using a Markov chain Monte Carlo method coupled with
radiative transfer calculations we study the dust and CO mass distribution. We find the dust is
distributed in a ring with a radius of 86:0 0:4 AU and a radial width of 23:2 1:0 AU. At
this frequency the ring radius is smaller than in the optical, revealing grain size segregation
expected due to radiation pressure. We also report on the detection of low level continuum
emission beyond the main ring out to 200 AU. We model the CO emission in the non-LTE
regime and we find that the CO is co-located with the dust, with a total CO gas mass ranging
between 1:2 10 6 M and 2:9 10 6 M, depending on the gas kinetic temperature and
collisional partners densities. The CO densities and location suggest a secondary origin, i.e.
released from icy planetesimals in the ring. We derive a CO cometary composition that is
consistent with Solar system comets. Due to the low gas densities it is unlikely that the gas is
shaping the dust distribution.
Is there an_exoplanet_in_the_solar_system
We investigate the prospects for the capture of the proposed Planet 9 from other
stars in the Sun’s birth cluster. Any capture scenario must satisfy three conditions:
the encounter must be more distant than ∼ 150 au to avoid perturbing the Kuiper
belt; the other star must have a wide-orbit planet (a & 100 au); the planet must be
captured onto an appropriate orbit to sculpt the orbital distribution of wide-orbit
Solar System bodies. Here we use N-body simulations to show that these criteria may
be simultaneously satisfied. In a few percent of slow close encounters in a cluster,
bodies are captured onto heliocentric, Planet 9-like orbits. During the ∼ 100 Myr
cluster phase, many stars are likely to host planets on highly-eccentric orbits with
apastron distances beyond 100 au if Neptune-sized planets are common and susceptible
to planet–planet scattering. While the existence of Planet 9 remains unproven, we
consider capture from one of the Sun’s young brethren a plausible route to explain such
an object’s orbit. Capture appears to predict a large population of Trans-Neptunian
Objects (TNOs) whose orbits are aligned with the captured planet, and we propose
that different formation mechanisms will be distinguishable based on their imprint on
the distribution of TNOs
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This research article explores how the orbital configuration of Kepler-62f, a potentially habitable exoplanet in a five-planet system, could affect its climate and habitability. N-body simulations were used to determine the stable range of orbital eccentricities for Kepler-62f. Climate simulations using two global climate models then examined the planet's surface habitability across this range of eccentricities and for different atmospheric compositions. The simulations found multiple combinations of orbital and atmospheric parameters that could allow for surface liquid water on Kepler-62f, including higher orbital eccentricities coupled with high planetary obliquity or atmospheric CO2 levels above 3 bars.
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Planets in highly eccentric orbits form a class of objects not seen within our Solar System. The most extreme case known amongst these objects is the planet orbiting HD 20782, with an orbital period of 597 days and an eccentricity of 0.96. Here we present new data and analysis for this system as part of the Transit Ephemeris Refinement and Monitoring Survey (TERMS). We obtained CHIRON spectra to perform an independent estimation of the fundamental stellar parameters. New radial velocities from AAT and PARAS observations during periastron passage greatly improve our knowledge of the eccentric nature of the orbit. The combined analysis of our Keplerian orbital and Hipparcos astrometry show that the inclination of the planetary orbit is > 1.22◦, ruling out stellar masses for the companion. Our long-term robotic photometry show that the star is extremely stable over long timescales. Photometric monitoring of the star during predicted transit and periastron times using MOST rule out a transit of the planet and reveal evidence of phase variations during periastron. These possible photometric phase variations may be caused by reflected light from the planet’s atmosphere and the dramatic change in star–planet separation surrounding the periastron passage.
Lightyear
A light year is a unit of distance used to measure large distances in space. It is defined as the distance that light travels in one year, which is about 9.46 trillion kilometers. Looking at distant objects in the universe means seeing them as they appeared in the past, since it takes time for their light to reach us - the further away an object is, the further back in time we are seeing it. The universe is estimated to be at least 156 billion light years in size.
Evidence for a_distant_giant_planet_in_the_solar_system
A descoberta de um novo planeta, atualmente não é uma manchete que chama tanto assim a atenção das pessoas. Muito disso, graças ao Telescópio Espacial Kepler, que já descobriu quase 2000 exoplanetas e todo instante uma nova descoberta é anunciada, certo? Mais ou menos, a descoberta anunciada hoje, dia 20 de Janeiro de 2016, é um pouco diferente, pois não se trata de um exoplaneta, e sim de um novo planeta no Sistema Solar, e esse é um fato que intriga os astrônomos a muitos e muitos anos.
Porém, temos que ir com calma com esses anúncios. No artigo aceito para publicação no The Astronomical Journal (artigo no final do post), os autores, Mike Brown e Konstantin Batygin, do Instituto de Tecnologia da Califórnia, apresentaram o que eles dizem ser evidências circunstâncias fortes para a existência de um grande planeta ainda não descoberto, talvez, com uma massa 10 vezes a massa da Terra, orbitando os confins do nosso Sistema Solar, muito além da órbita de Plutão. Os cientistas inferiram sua presença, por meio de anomalias encontradas nas órbitas de seis objetos do chamado Cinturão de Kuiper.
O objeto, que os pesquisadores estão chamando de Planeta Nove, não chega muito perto do Sol, no ponto mais próximo da sua órbita ele fica a 30.5 bilhões de quilômetros, ou seja, cinco vezes a distância entre o Sol e Plutão. Apesar do seu grande tamanho, ele é muito apagado, e por isso ninguém até o momento conseguiu observá-lo.
Não existe ainda uma confirmação observacional da descoberta, mas as evidências são tão fortes que fizeram com que outros especialistas como Chad Trujilo do Observatório Gemini no Havaí e David Nesvorny, do Southwest Research Institute em Boulder no Colorado, ficassem impressionados e bem convencidos de que deve mesmo haver um grande planeta nas fronteiras da nossa vizinhança cósmica.
saturn
Saturn is the sixth planet from the sun. Some key facts:
- It was discovered by ancient peoples and named after the Roman god Saturn. Galileo first observed its rings in 1610 using a telescope.
- It has a orbital period of around 29 earth years and its most notable moon, Titan, is larger than Mercury and has lakes of liquid methane and ethane.
- Saturn's rings were discovered by Galileo and Huygens and are composed of millions of chunks of ice and rock.
- To survive on Saturn one would need protection from the cold temperatures and high winds, and secure food that wouldn't float away.
KNAC_Lewis_Banales_Hughes_final
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.
Hidden lives v2
Galaxies are massive collections of stars, gas and dust held together by gravity. There are different types of galaxies including spiral, elliptical and irregular galaxies. Galaxies form from dense fluctuations after the Big Bang and their structure depends on the initial rate of star formation - faster formation leads to elliptical galaxies while slower formation allows gas to collapse into disks forming spiral galaxies. Observations of the rotation curves of galaxies and hot gas show that galaxies contain far more mass than the visible mass accounted for, known as "hidden mass". Dark matter in the form of weakly interacting massive particles is currently the best candidate to explain this missing mass.
Astronomy - State of the Art - Telescopes
Telescopes help us learn about the universe by collecting more light than the human eye and seeing more detail. Larger telescopes collect more light and see sharper images, but the atmosphere limits ground-based telescope resolution. Telescope size has grown exponentially over time. Adaptive optics and interferometry allow telescopes to approach the theoretical resolution limit. While space telescopes avoid many atmospheric limitations, they are much more expensive to build and operate. The Hubble Space Telescope has revolutionized astronomy through high-quality images across the electromagnetic spectrum.
The parkes hi zone of avoidance survey
This document summarizes a blind HI survey of the southern Milky Way zone of avoidance conducted with the Parkes radio telescope. The survey detected 883 galaxies at Galactic longitudes 212° < l < 36° and latitudes |b| < 5° to a sensitivity of 6 mJy per 27 km/s channel. Fifty-one percent of detections had known optical/near-infrared counterparts, while 27% had new counterparts identified. The survey delineated large-scale structures in the Puppis and Great Attractor regions for the first time. Several newly identified galaxy concentrations and clusters were revealed that help trace the Great Attractor Wall.
Other Solar Systems and Life in the Universe
The presentation features the history of exoplanets, its proponents/discoverers and its recent studies and developments. Videos may not be available for PCs which does not support video clip formats..
Pre assessment test
This document appears to be a pre-assessment test containing multiple choice and fill-in-the-blank grammar questions. It tests parts of speech, punctuation, sentence structure, and includes a short writing prompt using the word "role". The document contains the student's name and date at the top and includes sections on grammar, punctuation, fragments, and a writing prompt. It provides a score sheet for the student to receive a score after completing the assessment.
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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.
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This document summarizes the steps taken to calculate the intersection point and speed of North Korean and American missiles hypothetically launched at the moon. It shows the work done to find that the missiles would intersect at approximately 10.4 days and 232,376.7 miles from Earth. It then calculates the speeds of each missile in miles per hour and kilometers per hour. It concludes that the American missile was able to intercept and destroy the North Korean missile in time to save the moon.
Math Project
This document summarizes the steps taken to calculate the intersection point and speed of North Korean and American missiles hypothetically racing to destroy the moon. It is determined that the American missile would intercept the North Korean missile at around 10.4 days and 232,376 miles from Earth, just in time to save the moon based on its average distance from Earth of 233,818 miles. However, it is noted that errors could occur due to rounding and because the moon's distance varies in its elliptical orbit.
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The Hubble Space Telescope is a robotic telescope located 593 km above Earth's surface. Named after Edwin Hubble, it was launched in 1990 as a joint NASA and ESA project. Hubble can obtain higher resolution images at 0.1 seconds of arc. The document then provides 10 examples of Hubble's best photos, which include galaxies, nebulae, and other celestial objects located between 2.5 to 114 million light years from Earth. Additional photos from Hubble are also presented showing various planets, moons, stars, and other astronomical phenomena in our solar system and beyond. The last photo shown is the Eagle Nebula, located in the constellation Serpens, which features young stars forming within gaseous emissions.
Hubble
The Hubble Space Telescope is a robotic telescope located 593 km above Earth's surface. Named after Edwin Hubble, it was launched in 1990 as a joint NASA and ESA project. Hubble weighs 11 tons and can obtain images with a resolution of 0.1 seconds of arc. The document then provides 10 examples of Hubble's best photographs, which include galaxies, nebulae, and other celestial objects located between 2.5 to 114 million light years from Earth. It concludes by showing an image of the Eagle Nebula, where young stars are forming within gaseous emissions.
Hubble
The Hubble Space Telescope is a robotic telescope located 593 km above Earth's surface. Named after Edwin Hubble, it was launched in 1990 as a joint NASA and ESA project. Hubble weighs 11 tons and can obtain images with a resolution of 0.1 seconds of arc. Some of Hubble's most famous images include the Galaxy Hat, the Eskimo Nebula, and the Hourglass Nebula. Other images show planets in our solar system, nebulae, galaxies, and more distant objects in space.
Hubble
The Hubble Space Telescope is a robotic telescope located 593 km above Earth's surface. Named after Edwin Hubble, it was launched in 1990 as a joint NASA and ESA project. Hubble weighs 11 tons and can obtain images with a resolution of 0.1 seconds of arc. The document then provides 10 examples of Hubble's best photographs, which include galaxies, nebulae, and other celestial objects located between 2.5 to 114 million light years from Earth. It concludes by showing an image of the Eagle Nebula, where young stars are forming within gaseous emissions.
Term Project Poster
This document discusses ultra-compact binary star systems that emit gravitational waves (GWs) due to their short orbital periods and high masses. It provides an overview of GWs based on Einstein's theory of general relativity, which predicts that massive, accelerating objects will produce ripples in spacetime. The proposed LISA mission aims to directly detect these GWs using a triangle-shaped array of satellites that will measure fluctuations in spacetime caused by passing GWs. Data is presented on 10 known ultra-compact binary systems in the Milky Way, showing their properties allow for calculations of expected GW strain, orbital decay rates, coalescence times, and luminosities.
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An increasing number of observations have shown that gaseous debris discs are not an
exception. However, until now we only knew of cases around A stars. Here we present the first
detection of 12CO (2-1) disc emission around an F star, HD 181327, obtained with ALMA
observations at 1.3 mm. The continuum and CO emission are resolved into an axisymmetric
disc with ring-like morphology. Using a Markov chain Monte Carlo method coupled with
radiative transfer calculations we study the dust and CO mass distribution. We find the dust is
distributed in a ring with a radius of 86:0 0:4 AU and a radial width of 23:2 1:0 AU. At
this frequency the ring radius is smaller than in the optical, revealing grain size segregation
expected due to radiation pressure. We also report on the detection of low level continuum
emission beyond the main ring out to 200 AU. We model the CO emission in the non-LTE
regime and we find that the CO is co-located with the dust, with a total CO gas mass ranging
between 1:2 10 6 M and 2:9 10 6 M, depending on the gas kinetic temperature and
collisional partners densities. The CO densities and location suggest a secondary origin, i.e.
released from icy planetesimals in the ring. We derive a CO cometary composition that is
consistent with Solar system comets. Due to the low gas densities it is unlikely that the gas is
shaping the dust distribution.
Is there an_exoplanet_in_the_solar_system
We investigate the prospects for the capture of the proposed Planet 9 from other
stars in the Sun’s birth cluster. Any capture scenario must satisfy three conditions:
the encounter must be more distant than ∼ 150 au to avoid perturbing the Kuiper
belt; the other star must have a wide-orbit planet (a & 100 au); the planet must be
captured onto an appropriate orbit to sculpt the orbital distribution of wide-orbit
Solar System bodies. Here we use N-body simulations to show that these criteria may
be simultaneously satisfied. In a few percent of slow close encounters in a cluster,
bodies are captured onto heliocentric, Planet 9-like orbits. During the ∼ 100 Myr
cluster phase, many stars are likely to host planets on highly-eccentric orbits with
apastron distances beyond 100 au if Neptune-sized planets are common and susceptible
to planet–planet scattering. While the existence of Planet 9 remains unproven, we
consider capture from one of the Sun’s young brethren a plausible route to explain such
an object’s orbit. Capture appears to predict a large population of Trans-Neptunian
Objects (TNOs) whose orbits are aligned with the captured planet, and we propose
that different formation mechanisms will be distinguishable based on their imprint on
the distribution of TNOs
T he effect_of_orbital_configuration)_on_the_possible_climates_and_habitabili...
This research article explores how the orbital configuration of Kepler-62f, a potentially habitable exoplanet in a five-planet system, could affect its climate and habitability. N-body simulations were used to determine the stable range of orbital eccentricities for Kepler-62f. Climate simulations using two global climate models then examined the planet's surface habitability across this range of eccentricities and for different atmospheric compositions. The simulations found multiple combinations of orbital and atmospheric parameters that could allow for surface liquid water on Kepler-62f, including higher orbital eccentricities coupled with high planetary obliquity or atmospheric CO2 levels above 3 bars.
Evidence for reflected_lightfrom_the_most_eccentric_exoplanet_known
Planets in highly eccentric orbits form a class of objects not seen within our Solar System. The most extreme case known amongst these objects is the planet orbiting HD 20782, with an orbital period of 597 days and an eccentricity of 0.96. Here we present new data and analysis for this system as part of the Transit Ephemeris Refinement and Monitoring Survey (TERMS). We obtained CHIRON spectra to perform an independent estimation of the fundamental stellar parameters. New radial velocities from AAT and PARAS observations during periastron passage greatly improve our knowledge of the eccentric nature of the orbit. The combined analysis of our Keplerian orbital and Hipparcos astrometry show that the inclination of the planetary orbit is > 1.22◦, ruling out stellar masses for the companion. Our long-term robotic photometry show that the star is extremely stable over long timescales. Photometric monitoring of the star during predicted transit and periastron times using MOST rule out a transit of the planet and reveal evidence of phase variations during periastron. These possible photometric phase variations may be caused by reflected light from the planet’s atmosphere and the dramatic change in star–planet separation surrounding the periastron passage.
Lightyear
A light year is a unit of distance used to measure large distances in space. It is defined as the distance that light travels in one year, which is about 9.46 trillion kilometers. Looking at distant objects in the universe means seeing them as they appeared in the past, since it takes time for their light to reach us - the further away an object is, the further back in time we are seeing it. The universe is estimated to be at least 156 billion light years in size.
Evidence for a_distant_giant_planet_in_the_solar_system
A descoberta de um novo planeta, atualmente não é uma manchete que chama tanto assim a atenção das pessoas. Muito disso, graças ao Telescópio Espacial Kepler, que já descobriu quase 2000 exoplanetas e todo instante uma nova descoberta é anunciada, certo? Mais ou menos, a descoberta anunciada hoje, dia 20 de Janeiro de 2016, é um pouco diferente, pois não se trata de um exoplaneta, e sim de um novo planeta no Sistema Solar, e esse é um fato que intriga os astrônomos a muitos e muitos anos.
Porém, temos que ir com calma com esses anúncios. No artigo aceito para publicação no The Astronomical Journal (artigo no final do post), os autores, Mike Brown e Konstantin Batygin, do Instituto de Tecnologia da Califórnia, apresentaram o que eles dizem ser evidências circunstâncias fortes para a existência de um grande planeta ainda não descoberto, talvez, com uma massa 10 vezes a massa da Terra, orbitando os confins do nosso Sistema Solar, muito além da órbita de Plutão. Os cientistas inferiram sua presença, por meio de anomalias encontradas nas órbitas de seis objetos do chamado Cinturão de Kuiper.
O objeto, que os pesquisadores estão chamando de Planeta Nove, não chega muito perto do Sol, no ponto mais próximo da sua órbita ele fica a 30.5 bilhões de quilômetros, ou seja, cinco vezes a distância entre o Sol e Plutão. Apesar do seu grande tamanho, ele é muito apagado, e por isso ninguém até o momento conseguiu observá-lo.
Não existe ainda uma confirmação observacional da descoberta, mas as evidências são tão fortes que fizeram com que outros especialistas como Chad Trujilo do Observatório Gemini no Havaí e David Nesvorny, do Southwest Research Institute em Boulder no Colorado, ficassem impressionados e bem convencidos de que deve mesmo haver um grande planeta nas fronteiras da nossa vizinhança cósmica.
saturn
Saturn is the sixth planet from the sun. Some key facts:
- It was discovered by ancient peoples and named after the Roman god Saturn. Galileo first observed its rings in 1610 using a telescope.
- It has a orbital period of around 29 earth years and its most notable moon, Titan, is larger than Mercury and has lakes of liquid methane and ethane.
- Saturn's rings were discovered by Galileo and Huygens and are composed of millions of chunks of ice and rock.
- To survive on Saturn one would need protection from the cold temperatures and high winds, and secure food that wouldn't float away.
KNAC_Lewis_Banales_Hughes_final
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.
Hidden lives v2
Galaxies are massive collections of stars, gas and dust held together by gravity. There are different types of galaxies including spiral, elliptical and irregular galaxies. Galaxies form from dense fluctuations after the Big Bang and their structure depends on the initial rate of star formation - faster formation leads to elliptical galaxies while slower formation allows gas to collapse into disks forming spiral galaxies. Observations of the rotation curves of galaxies and hot gas show that galaxies contain far more mass than the visible mass accounted for, known as "hidden mass". Dark matter in the form of weakly interacting massive particles is currently the best candidate to explain this missing mass.
Astronomy - State of the Art - Telescopes
Telescopes help us learn about the universe by collecting more light than the human eye and seeing more detail. Larger telescopes collect more light and see sharper images, but the atmosphere limits ground-based telescope resolution. Telescope size has grown exponentially over time. Adaptive optics and interferometry allow telescopes to approach the theoretical resolution limit. While space telescopes avoid many atmospheric limitations, they are much more expensive to build and operate. The Hubble Space Telescope has revolutionized astronomy through high-quality images across the electromagnetic spectrum.
The parkes hi zone of avoidance survey
This document summarizes a blind HI survey of the southern Milky Way zone of avoidance conducted with the Parkes radio telescope. The survey detected 883 galaxies at Galactic longitudes 212° < l < 36° and latitudes |b| < 5° to a sensitivity of 6 mJy per 27 km/s channel. Fifty-one percent of detections had known optical/near-infrared counterparts, while 27% had new counterparts identified. The survey delineated large-scale structures in the Puppis and Great Attractor regions for the first time. Several newly identified galaxy concentrations and clusters were revealed that help trace the Great Attractor Wall.
Other Solar Systems and Life in the Universe
The presentation features the history of exoplanets, its proponents/discoverers and its recent studies and developments. Videos may not be available for PCs which does not support video clip formats..
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G10 Science :Earth and Space -Learner's Module 1st Quarter
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1. d - the location of the epicenter
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This document discusses different types of volcanoes. It provides descriptions of cinder cones, shield volcanoes, composite volcanoes, and lava domes. Cinder cones are symmetrical cones up to 1,200 feet tall formed from a single vent. Shield volcanoes are very broad with shallow slopes and can be over 30,000 feet tall. Composite volcanoes are also known as stratovolcanoes, ranging from 1-10 km wide and up to 10,000 feet tall with steep slopes. They have explosive, dangerous eruptions. Lava domes are much smaller formations that occur when lava is too viscous to flow, piling up in a dome shape around 100 feet tall. Examples of each type
Volcanoes
Volcanoes are openings in the Earth's crust that eject lava, pyroclasts, and gases during eruptions. They consist of cones formed from accumulated volcanic materials and craters or calderas at the peak. Magma located below ground hardens into lava when it reaches the surface. Volcanoes can be cinder cones, shield cones, or composite cones depending on their composition and shape. They can be active, dormant, or extinct based on activity levels and pose dangers like gases, lava flows, and lahars during eruptions but also provide agricultural, energy, industrial, and tourism benefits.
Constellations
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Constellations
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Constellations
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Qasas un-nabiyeen volume 4 قصص النبيين الجلد الرابع
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The document provides details about a teacher training workshop on observing the transit of Venus. It includes the schedule, topics to be covered in lectures and demonstrations, and objectives of the workshop. The workshop aims to help teachers understand the importance of the transit, learn how to observe it safely and hold related activities, and discuss support options. It will cover the science and history of transits, observation techniques, and making observation equipment.
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みなさんこんにちはこれ何文字まで入るの？40文字以下不可とか本当に意味わからないけどこれ限界文字数書いてないからマジでやばい文字数いけるんじゃないの？えこ...
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Pre assessment
- 2. Q1. Arrange the following objects in the order of their distances from the Earth, which one is in the middle? (a) The asteroid Ada; (b) The Kuiper Belt Object Sedna; (c) The galaxy M31; (d) The planet Neptune; (e) The quasar 3C273.
- 5. Q2. A large dot in a star atlas represents (a) a big star; (b) a bright star; (c) a nearby galaxy; (d) a large star cluster; (e) an important double star.
- 7. Q3. The main reason astronomers prefer large telescopes is that they (a) collect more light; (b) are easier to track stars; (c) have higher magnifications; (d) can be controlled by computers; (e) can easily offset the effect of atmosphere turbulence.
- 9. Q4. Which of the following kinds of EM waves can pass through our atmosphere without significant absorption? (a) gamma-ray; (b) infrared; (c) microwave; (d) ultraviolet; (e) x-ray.
- 10. Credit: Addison Wesley Atmospheric Window 大氣視窗
- 12. Q5. A few dark lines and bright lines are present in the spectrum of a star. Which of the following statements concerning the spectrum of this star is correct? (a) The bright lines belong to its blackbody spectrum; (b) The bright lines are called emission lines; (c) The dark lines belong to its blackbody spectrum; (d) Doppler effect is responsible for the production of the dark lines; (e) The frequencies of the bright and dark lines depend only the surface temperature of the star.
- 15. Q6. (First statement): Since Jupiter-Sun distance is larger than the Earth-Sun distance, (Second statement): therefore, the angular size of the Sun for an Earth-based observer is larger than that for a Jupiter-based observer.
- 16. Size and distance in different scales
- 17. Q7. (First statement): Since the Gregorian calendar demands exactly one leap year in every four consecutive years, (Second statement): therefore, there are 24 leap years between 2001 and 2101.
- 19. Q8. (First statement): Since the ancient Greek divided the whole celestial sphere into 88 constellations, (Second statement): therefore, each star can only belong to one constellation.
- 21. Q9. (First statement): Since Kepler's first law states that the orbit of a planet around the Sun is elliptical, (Second statement): therefore, the magnitude of the gravitational force of a planet due to the Sun is greatest when their mutual distance is the smallest.
- 22. Kepler’s laws of planetary motion • Law of ellipses – the orbit of a planet about the sun is an ellipse with the sun at one focus • Law of equal areas – a line joining a planet and the sun sweeps out equal areas in equal intervals of time • Law of harmonies – the square of a planet’s sidereal period around the sun is directly proportional to the cube of the length of its orbit’s semi-major axis, a a
- 23. Q10. (First statement): Since the visual magnitude is a linear scale in light intensity, (Second statement): therefore, a magnitude 1.0 star is about 6.3 times brighter than a magnitude 3.0 star.
- 25. Q11. (First statement): Since the first step of solar system formation is the ejection of accretion disk within about 1 billion years, (Second statement): therefore, the age of our Solar System is about 1 to 2 billion years.
- 27. Q12. (First statement): Since the rotational period of the Moon relative to the Earth is exactly equal to the orbital period of the Moon relative to the Sun, (Second statement): therefore, the Moon is in synchronous rotation around the Earth.
- 29. Q13. (First statement): Since the axis of rotation of Venus is almost perpendicular to the orbital plane, (Second statement): therefore, seasons on Venus is very apparent.
- 32. Q14. (First statement): Since methane in the atmosphere of Neptune scatters blue light, (Second statement): therefore, Neptune is blue in color.
- 35. Q15. (First statement): Since meteoroids are particles in space that may enter the Earth's atmosphere upon the gravitational pull of the Earth, (Second statement): therefore, meteor showers can sometimes been seen on Earth.