Arecibo Observatory took radar images of asteroid 1998 QE2 and its moon as the space rock sailed safely past earth. The sequence of images show a dark, cratered asteroid 3.0 kilometers across (1.9 miles) across with a companion moon about 750 meters (2500 feet) in size. Both the asteroid and its moon passed 6 million kilometers (3.8 million miles) from earth. ... Radar images of asteroid 1998 QE2 (bottom) and its satellite (top) on June 6. ... Comparisons of QE2 to the size of an ocean liner . ...

... Dept. for Astrometry & Space Geodynamics . ... Dept. for Physics of Stars&Galaxies . ... Dept. for Physics of Planetary Systems . ... Science . ... All Pages . ... Research of the stars with planets which pass apparent star disk (transiting exoplanets). The transit method based on a detection star brightness decrease during a passing of planet in front of its disk. Observed brightness system decries when planet pass star disk and its volume depend of the relative sizes star and planet. ...

DARK MATTER IN THE UNIVERSE Paul J. Green UNSEEN MASS: Astronomers studying the motions of stars and galaxies throughout the universe have long noticed a strange discrepancy. Stars move around galaxies as if pulled by ten times the matter that we can see. ... GRAVITATIONAL LENSING: Since dark matter by definition cannot be directly observed, several recent searches have instead exploited the predicted gravitational effects of its mass on the observed light from nearby stars. ...

... Exposure Time Calculator (ETC) . Survey processing . ... VISTA is a 4-m class wide field survey telescope for the southern hemisphere, equipped with a near infrared camera (1.65 degree diameter field of view at VISTA's nominal pixel size) containing 67 million pixels of mean size 0.34 arcsec and available broad band filters at Z,Y,J,H,K s and a narrow band filter at 1.18 micron. A wide field visible camera, if constructed, could also be used on VISTA. ... Tile . ... ESO VISTA Public Surveys . ...

... Astrophysics Group . ... Optical Interferometry . Very Large Telescope Interferometer . ... Optical Interferometry Team Publications . ... VSI is currently the subject of a Phase A study, performed by a European consortium led by Laboratoire d?Astrophysique de l?Observatoire de Grenoble . The Cavendish optical interferometry group are members of the consortium, contributing mostly to the studies of the VSI internal fringe tracker and to the definition of the science cases. ...

MAIN PAGE . ... Nova Cygni August 1975! ... 1975/76: Comet West! ... Dr. Richard West (4th from left) & AAL members visiting SES Betzdorf on occasion of our club's 25th anniversary - October 1996 . Comet West Information . ... It was the brightest comet visible from Earth since Comet West in 1976. ... 1997: Comet Hale-Bopp! ... Thus Comet Hale-Bopp never got closer to Earth than Earth gets to the Sun. ... Comet Hale-Bopp JPL Page . ... 1999: Total solar eclipse over Luxembourg! ...

... Meade Series 4000 Nebular Filters incorporate the very latest in interference coatings technology. ... Technical Basis of the Meade Broadband Nebular Filter: As shown in the transmission graph below, the Meade Broadband Nebular Filter strongly rejects the light of sodium- and mercury-vapor lights as well as natural airglow and auroral emissions. ... Meade Series 4000 Narrowband Nebular Filters . ... Meade Series 4000 Oxygen-III Nebular Filters . ... Meade Series 4000 Photo-Visual Color Filters . ...

ARCSAT ID NUMBER: AS05 DESCRIPTIVE TITLE: Time Series photometry of F/G/K + M dwarf eclipsing binaries PI: Leslie Hebb OBSERVER(S): Leslie Hebb UNCERTIFIED/UNTRAINED OBSERVERS: HWS students, Michelle Gomez and Betty Vasquez COLLABORATORS: Yilen Gomez Maqueo Chew CONTACT INFORMATION: Leslie Hebb , hebb @hws.edu, 206-618-9843 TIME REQUESTED: 1 week in April INSTRUMENT: Flarecam FILTERS: griz COMMENTS: no BRIEF SCIENCE JUSTIFICATION ...

Next: Ejectors in Massive Binary Previous: Artificial Galaxy: Full Matrix . The first version of the Scenario Machine was aimed especially at the simulation of massive binary star evolution. ... First, there is a large class of intermediate mass binaries (say, consisting initially of 8 + 5 solar masses) that can also produce NS and thus lead to the formation of a bright X-ray source. ... Next: Ejectors in Massive Binary Previous: Artificial Galaxy: Full Matrix Mike E. Prokhorov . ...

ECLIPSES, TRANSITS OF MERCURY AND VENUS . Year 1999 . Year 2000 . Year 2001 . Year 2002 . Year 2003 . Year 2004 . Year 2005 . ... Total solar eclipse . ... Transit of Mercury across the solar disk . ... Total lunar eclipse . ... Partial solar eclipse . ... Partial lunar eclipse . ... Annular solar eclipse . ... Penumbral lunar eclipse . ... big map . ... Transit of Venus across the solar disk . ... Annular-total solar eclipse . ... Non-central annular solar eclipse . ...

RELATIVE SUNSPOT NUMBERS Description of Data from SGD Explanation of Data Reports: Relative Sunspot Numbers -- The relative sunspot number is an index of the activity of the entire visible disk of the Sun. ... The provisional daily Zurich relative sunspot numbers, Rz, were based upon observations made at Zurich and its two branch stations in Arosa and Locarno and communicated by M. Waldmeier of the Swiss Federal Observatory. ... This indicates the uncertainty above and below the predicted number. ...

... ON THE ROLE OF LARGE-SCALE PLASMA IRREGULARITIES AT THE FINAL STAGE OF ANOMALOUS ABSOPTION DEVELOPING UNDER HF HEATING OF THE IONOSPHERE . ... Fig. ... With the aid of numerical statistical modeling based on multiple ray tracing it is shown that in presence of large-scale irregularities the reflected signal amplitude mean value is increased significantly. ... Dependence of the mean amplitude of the reflected from the ionosphere signal on the large-scale (10-50 km) electron density irregularity level...

You Can Make Stellar Images Brighter . Articles | ... A few months ago I wrote an article titled "You Can’t Make Them Brighter". So why am I now writing that you can make them brighter. ... The image of a focused star is actually a small disk called the Airy disk, named after the 19 th century scientist Sir George Airy. ... For a given aperture, a smaller Airy disk means that the light is focused to a smaller disk and is therefore brighter. ... www.astronomy.net . About Astronomy Net | ...

... This glossary is not meant to be an exhaustive list of techno-definitions. ... Is there a term you don't see here? ... Do you know how to pronounce the CONSTELLATIONS , STARS , or the PLANETS and their MOONS ? ... First Law - the orbit of each planet is an ellipse with the sun at a focus . ... LIGHT BUCKET: A common slang term for a large apertures . ... LIGHT POLLUTION: The illumination of the night sky caused by artificial light sources on the ground (streetlights, billboards, etc.) ...

... Spherical aberration, coma, and astigmatism are also easily observed using the star test. ... Off-axis images are complex. ... Fig. ... Diffraction by a circular aperture as a function of defocus for no aberration Airy Disk 1 wave defocus Less than 1 wave defocus Fig. ... Diffraction by a circular aperture as a function of defocus for third-order spherical aberration Paraxial Focus Small distance inside paraxial focus Moderate distance from marginal focus Immediate neighborhood of marginal focus Fig...

... Measurements of magnetic fields on scales larger than galaxy clusters are needed to distinguish between fields generated in the primordial Universe and those generated at later epochs, with implications for particle physics, cosmology, and astrophysics. ... In this talk I will review mechanisms for generating magnetic fields across cosmic time, implications for post-recombination physics, and current observational constraints on intergalactic magnetic fields. ...

... An overall criterion for standard-star selection is the accuracy needed in the final results: if you need more accuracy, you will need more standard stars. ... While it is possible to get a rough estimate of the extinction by observing different standard stars at high and low airmasses, the relatively large conformity errors in most photometric systems, together with the low accuracy of some standards, make this method very inefficient (see Young [ 10 ], p.178). ...

The telescope configured for measurements of exoplanet transit light curves is seen from the north side in this May 2010 photo. Lower portions of the dome have been insulated to reduce daytime heating by radiation from the warm metal dome. ... The interior of the dome is seen soon after the encoder upgrade in February 2007. ... Karen Collins, a research astronomer specializing in exoplanets, helped with the telescope installation in August 2006. ... kielkopf at louisville dot edu . ...

Total solar eclipse occurs on Friday, 1 August, 2008, in northern Canada, the Arctic, and Asia. The 2008 event will be visible in northern Canada, Greenland, Siberia, Mongolia and parts of China. The path of totality of the 2008 eclipse passes a couple of particularly interesting destinations and cities: Novosibirsk, in Siberia, Barnaul in Southern Siberia in Altai region, and the Altai Mountains region. ... Time of Novosibirsk . ... Solar Eclipse 2008 . Total Eclipse 2008 in Siberia . ...

... Visualization of such data has now become a complex 4-D data-mining problem, combining space and time, and finding interesting events in these large datasets. ... NEMO (Teuben 1994) and Starlab are traditional programming environments with which N-body simulations can be setup, run, and analyzed. ... By adding complete orbital information for a select number of stars we have started fully interactive data mining of our 4-D spacetime histories of these star cluster simulations runs. ...