http://en.wikipedia.org/wiki/Quasistarhttp://arxiv.org/abs/1102.5098Large clouds of hydrogen and helium were common in the early universe. Begelman says that if such a cloud collapsed into a massive star, a dense knot of the gas could pile up so rapidly in its core that it would collapse into a small black hole.When that happens in stars just a few times as massive as the Sun, the enormous energy released is enough to blast away the surrounding layers of gas, revealing a brilliant supernova explosion.But as long as a quasistar is at least 1000 times the mass of the Sun, its great bulk could have absorbed all that energy, containing the supernova with no more than a shudder, becoming a black-hole sun.
MDIS – Mercury Dual Imaging System – wide and narrow angle imagersGRNS – Gamma ray and neutron spectrometer - This instrument will detect gamma rays and neutrons that are emitted by radioactive elements on Mercury's surface or by surface elements that have been stimulated by cosmic rays. It will be used to map the relative abundances of different elements and will help to determine if there is ice at Mercury's poles, which are never exposed to direct sunlight. Magnetometer (MAG): This instrument is at the end of a 3.6 meter (nearly 12-foot) boom, and will map Mercury's magnetic field and will search for regions of magnetized rocks in the crust. Mercury Laser Altimeter (MLA): This instrument contains a laser that will send light to the planet's surface and a sensor that will gather the light after it has been reflected from the surface Mercury Atmospheric and Surface Composition Spectrometer (MASCS): This spectrometer is sensitive to light from the infrared to the ultraviolet and will measure the abundances of atmospheric gases, as well as detect minerals on the surface. Energetic Particle and Plasma Spectrometer (EPPS): EPPS measures the composition, distribution, and energy of charged particles (electrons and various ions) in Mercury's magnetosphere. Radio Science (RS): RS will use the Doppler effect to measure very slight changes in the spacecraft's velocity as it orbits Mercury. This will allow scientists to study Mercury's mass distribution, including variations in the thickness of its crust.
http://www.spacex.com/falcon9.phphttp://www.spacex.com/F9-001.phpLike Falcon 1, Falcon 9 is a two stage, liquid oxygen and rocket grade kerosene (RP-1) powered launch vehicle. It uses the same engines, structural architecture (with a wider diameter), avionics and launch system.The Falcon 9 tank walls and domes are made from aluminum lithium alloy. SpaceX uses an all friction stir welded tank, the highest strength and most reliable welding technique available. Like Falcon 1, the interstage, which connects the upper and lower stage for Falcon 9, is a carbon fiber aluminum core composite structure. The separation system is a larger version of the pneumatic pushers used on Falcon 1.
Space and Astronomy Update 04.03.11
NASA Ends Stardust• Comet hunter program• Decided to use lat of fuel for an experiment• Mission previously collected sample of comet dust from comet Wild2• Orbit was tweaked to meet Tempel 1 on 02/14 – Tempel1 was hit by an impact mission in 2006 but data was not successfully gathered • The Stardust flyby provided footage of the Tempel 1 crater
Physicists create heavier antimatter• Heaviest form of antimatter seen to date – Only anti-helium nuclei though
‘Quasi-stars’ spawned early black holes• A quasi-star is formed when a very large dust cloud coalesces to form a star. – If large enough it theoretically can have a black hole at its center. – Such a black hole can quickly grow to thousands of time the sun’s mass – The energy of such a star is formed of the radiation from its mass falling into the black hole at the core – Such a black hole eventually eats its star layers and anything close. It can reach a billion solar masses.
Sun-less habitable planets?• Dark matter could make it possible – In some models dark matter interacts with nuclei of regular matter atoms causing gravitation bounding. – Energy is released in the eventual annihilation of the dark matter deep within a planet – It is only expected sufficient interaction could occur near the center of galaxies however. – But once enough dark matter is bound the planet can self-sustain its heat for a very long time.
Near Earth Asteroid Surveys• As of today – 7922 NEOs, 824 of dia> 1 km, 1214 classed as potentially hazardous• Next phase expectations – Total of 50000 NEOs with diameter > 140m – 10,000 potentially hazardous• Earth asteroid scopes – PAN-starrs 1 operating in Hawaii, PAN-starrs 2 in 2012 and future plans for PAN Starrs 4 – Large Synoptic Survey Telescope for wide field survey is in the design phase
Dark Energy, Not an Illusion• New measurements of exploding stars support the theory• Universe expansion rate increasing – Dark energy was theorized to explain this – An alternate idea was that there was less matter in our area so less gravity• The new measurements give an expansion rate to high for the alternate theory – Though some now propose a void within a void • Epicycles, anyone?
Messenger: Mercury Mission• Why Mercury? – Odd day cycle (6 months log but 88 day orbit) – Only half mapped previously – Made of as much as 85% iron-core • Twice normally expected – Only other planet in system with global magnetic field • Mercury’s field is thought to have different origin
Messenger Mercury Probe• Schedule – August 3, 2004 -- MESSENGER Launch August 2005 -- Earth flyby October 2006 -- Venus flyby June 2007 -- Venus flyby January 2008 -- Mercury flyby October 2008 -- Mercury flyby September 2009 -- Mercury flyby March 2011 -- Yearlong science orbit of Mercury begins
Ultra cool brown Brown Dwarf?• Odd room temperature brown dwarf found – Apparently at a mere 30 C • Coolest found before this is 100 C. – Discovered using NASA’s Infrared Spitzer Telescope• Orbits a white dwarf 63 ly from Earth – Ways 7 times as much as Jupiter – Orbit is too wide to be considered as possibly a large planet
SpaceX: Something Big is Coming• Elon Musk of SpaceX will hold a press conference in Washington Tuesday – Thought to be about the Dragon spacecraft – But SpaceX already has a contract with NASA on this so perhaps something else? – Perhaps a Falcon 9 announcement? • EVENT: SpaceX CEO Elon Musk to Talk About the Next Big Thing TIME: 11:20 AM DATE: Tuesday, April 5th, 2011 • Webcast: http://www.visualwebcaster.com/spacex
SpaceX Falcon 9• Nine engine next generation after Falcon 1 – Nine Merlin engines • Engine proven in the Falcon 1 program – First commercial mission launch last June• Lowest rocket based prices to orbit – Capacity to Leo 10 metric tons • Cost ~$49M – Capacity to GEO 4500 kg • Roughly same cost
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