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: http://www.stsci.edu/~inr/thisweek1/2008/thisweek335.html
Дата изменения: Tue Dec 2 21:50:48 2008 Дата индексирования: Wed Jan 14 14:22:59 2009 Кодировка: Поисковые слова: star trail |
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| Program Number | Principal Investigator | Program Title | Links |
| 11103 | Harald Ebeling, University of Hawaii | A Snapshot Survey of The Most Massive Clusters of Galaxies | Abstract |
| 11110 | Stephan McCandliss, The Johns Hopkins University | Searching for Lyman alpha Emission from FUSE Lyman Continuum Candidates | Abstract |
| 11130 | Luis Ho, Carnegie Institution of Washington | AGNs with Intermediate-mass Black Holes: Testing the Black Hole-Bulge Paradigm, Part II | Abstract |
| 11158 | R. Michael Rich, University of California - Los Angeles | HST Imaging of UV emission in Quiescent Early-type Galaxies | Abstract |
| 11201 | Nitya Kallivayalil, Harvard University | Systemic and Internal motions of the Magellanic Clouds: Third Epoch Images | Abstract |
| 11213 | Gerard T. van Belle, California Institute of Technology | Distances to Eclipsing M Dwarf Binaries | Abstract |
| 11218 | Howard E. Bond, Space Telescope Science Institute | Snapshot Survey for Planetary Nebulae in Globular Clusters of the Local Group | Abstract |
| 11230 | Christopher P. O'Dea, Rochester Institute of Technology | HST FUV Observations of Brightest Cluster Galaxies: The Role of Star Formation in Cooling Flows and BCG Evolution | Abstract |
| 11289 | Jean-Paul Kneib, Laboratoire d'Astronomie Spatiale | SL2S: The Strong Lensing Legacy Survey | Abstract |
| 11612 | Kris Davidson, University of Minnesota - Twin Cities | Eta Carinae's Continuing Instability and Recovery - the 2009 Event | Abstract |
| 11943 | Douglas R. Gies, Georgia State University Research Foundation | Binaries at the Extremes of the H-R Diagram | Abstract |
| 11957 | Harold A. Weaver, The Johns Hopkins University Applied Physics Lab | Hubble Investigation of Asteroid 21 Lutetia in Support of the Rosetta Mission Flyby | Abstract |
| 11962 | Adam Riess, The Johns Hopkins University | A New Supernova in the Antennae; Narrowing in on the Hubble Constant and Dark Energy | Abstract |
GO 11213: Distances to Eclipsing M Dwarf Binaries
Artist's impression of a cool binary system
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Eclipsing binaries are stellar systems where the orbital plane lies in the line of
sight, leading to the components undergoing mutual eclipses. These systems are
extremely powerful probes of stellar properties, since (given the appropriate radial
velocity measurements) they permit direct measurement
of |
GO 11289: SL2S - The Strong Lensing Legacy Survey
ACS images of galaxy-galaxy Einstein ring lenses from the Sloan survey
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Gravitational lensing is a consequence the theory of general relativity. Its importance as an astrophysical tool first became apparent with the realisation (in 1979) that the quasar pair Q0957+561 actually comprised two lensed images of the same background quasar. In the succeeding years, lensing has been used primarily to probe the mass distribution of galaxy clusters, using theoretical models to analyse the arcs and arclets that are produced by strong lensing of background galaxies, and the large-scale mass distribution, through analysis of weak lensing effects on galaxy morphologies. Gravitational lensing can also be used to investigate the mass distribution of individual galaxies. Until recently, the most common background sources were quasars. Galaxy-galaxy lenses, however, offer a distinct advantage, since the background source is extended, and therefore imposes a stronger constraints on the mass distribution of the lensing galaxy than a point-source QSO. The CFHT Legacy survey provides a powerful tool for identifying candidate galaxy-galaxy lenses. Optical ground-based imaging, even from Hawaii, cannot match the results from a 2.4-metre telescope in orbit. Thus, the present program is using WFPC2 imaging to verify the nature of those candidates. The high resolution images can then be analysed to model the underlying mass distribution. |
GO 11957: Hubble Investigation of Asteroid 21 Lutetia in Support of the Rosetta Mission Flyby
A comparison between fly-by images of the asteroid Gaspra and the two martian satellites, Phobos
(lower) and Deimos (upper)
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ESA's Rosetta mission aims to make the first ever landing on a cometary nucleus. As such, it is a follow-up to the Giotto mission, which encountered, imaged and was sand-blasted by Comet Halley during the latter's 1986 perihelion passage. Rosetta was launched on 2 March 2004, and will rendezvous with Comet 67P/Churyumov-Gerasimenko in early 2014. After an extensive period of mapping the comet, Rosetta will release the lander, named Philae (the island in the Nile river where the Rosetta stone was found), which will land on the comet's surface and transmit back data on the chemical composition. On its way to Comet 67P/Churyumov-Gerasimenko, Rosetta will make a number of fly-bys of Earth and Mars, boosting the orbital energy, and will encounter two asteroids: 2867 Steins (September 5, 2008) and 21 Lutetia (July 10, 2010). The current HST observations are in preparation for the second encounter. Lutetia is a main-belt asteroid with an estimated diameter of 100 kilometres and a potentially unusual composition: although classified as a metallic (type M) asteroid, the spectral characteristics are somewhat unusual. Deep HST imaging with WFPC2 will be used to search for dust debris and for low-mass companions. |