... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... Risks Comparable to NEOs . ... The Increasing Rate of Discovery of Asteroids . ... Comet and Asteroid Collision Probabilities . ... Extreme albedo comets and the impact hazard (PDF Format) . ... Asteroid Impact Animations . ... Workshop on Scientific Requirements for Mitigation of Hazardous Comets and Asteroids - 2002 . ... The Spaceguard Survey Report, 1992 (PDF) . Tsunami from Asteroid/Comet Impacts . ...

... A Large Space Station Over Earth . ... 14.04.2010 . ... Credit Copyright: STS-131 Crew, Expedition 23 Crew, NASA Explanation: The International Space Station is the largest object ever constructed by humans in space. ... The station is so large that it could not be launched all at once -- it is being built piecemeal with large sections added continually by flights of the Space Shuttle . ... April . ... 2009 2010 . ... Publications with keywords: ISS - Earth . Publications with words: ISS - Earth . ...

Astronotes Armagh Planetarium's Stellar Blog! ... Solar System . ... Planets . ... This bizarrely shrunken planetary system was found by NASAтАЩs Kepler mission, hence the parent star has been named Kepler-11. ... Planetary scientist and Kepler science team member Jack Lissauer said ?These six planets are mixtures of rock and gases, possibly including water.тАЭ €аNone of these strange new worlds are likely to be home to any form of life; their surface conditions are simply too extreme. ...

... 2010 April 14 . A Large Space Station Over Earth . Credit: STS-131 Crew, Expedition 23 Crew, NASA . Explanation: The International Space Station is the largest object ever constructed by humans in space. ... The station is so large that it could not be launched all at once -- it is being built piecemeal with large sections added continually by flights of the Space Shuttle . ... On the far right, a crescent Earth slices through the blackness of space. ... About APOD | ...

... I t was long thought that Titan was the largest satellite in the solar system but recent observations have shown that Titan's atmosphere is so thick that its solid surface is slightly smaller than Ganymede's . ... R ecent observations with the Hubble Space Telescope show remarkable near infrared views of Titan's surface (right and top). ... T he observations by HST also indicate that Titan's rotation is in fact synchronous like most of Saturn's other moons. more images . ... Saturn .. ...

... ESO is building what will be the World's largest optical telescope array, The Very Large Telescope (VLT). The VLT Project organisation is responsible for the design and construction of the Unit Telescopes, including enclosures, optics, adapter-rotators and coating unit. ... Unit Telescopes Overview - This page is outdated, an update is in process. ... Secondary mirror (M2 Unit) - This page is outdated, an update is in process. ... Coating Unit - This page is outdated, an update is in process. ...

Titan . ... Hubble Space Telescope Images of Titan's surface . ... Later that year, it will release the European-built Huygens probe for a descent through Titan's atmosphere. ... This artist's rendering shows the European Space Agency's Huygens probe descending into the atmosphere of Saturn's moon Titan after being released by NASA's Cassini spacecraft. ... This artist's rendering shows the Huygens probe on the surface of Saturn's moon Titan after being released by NASA's Cassini spacecraft. ...

... Tonight's Sky . ... Observing . ... Sky this Month . ... Observing Podcasts . ... Astronomy for Kids . ... Observing springtime deep-sky objects with a large telescope . ... Seasonal Observing . ... How massive must a colliding body be to disturb Earth's orbit? ... Get instant access to subscriber content on Astronomy.com! ... If you are already registered on Astronomy.com, please log in below. ... Receive news, sky-event information, observing tips, and more from Astronomy's weekly email newsletter...

... Jay Apt (Ph.D.) . NASA Astronaut (Former) . ... PUBLICATIONS: Dr. Apt shared his images and knowledge in the publication Earth in Orbit : NASA Astronauts Photograph the Earth , written in conjunction with NASA scientists Michael Helfert and Justin Wilkinson and published by the National Geographic Society. ... From 1976 to 1980 he was a staff member of the Center for Earth & Planetary Physics, Harvard University, supporting NASA s Pioneer Venus Mission by making temperature maps of Venus from Mt. ...

... 142,800 Mean density (kg/m^3) .. ... 5.203 Rotation period (length of day in Earth hours).. 9.8 Revolution period (length of year) (in Earth years). 11.86 Obliquity (tilt of axis) (degrees).. 3.08 Orbit inclination (degrees).. 1.3 Orbit eccentricity.. 0.048 Mean surface temperature (K)........................ 120 (cloud tops) Visual geometric albedo.. 0.44 Atmospheric components.............................. 90% hydrogen, 10% helium, .07% methane Rings.. ...

... On the morning of Thursday, 26 February, amid the Gal pagos Islands, the Sun will fade from view. Not the culmination of ancient prophecy, but none less mystical, Earth's small Moon will be executing a slow slide past the enormous Sun. ... And anyone living in southern North America, Central America, northern South America, or on islands and cruise ships in the Caribbean Sea will, weather permitting, have the opportunity to experience the wonder of a solar eclipse. ...

Program Number . ... Gordon Drukier, Yale University . Shooting Stars: Looking for Direct Evidence of Massive Central Black Holes in Globular Clusters . Abstract . ... Hubble Heritage Observations of Arp 148 . ... The Sloan Digital Sky Survey (SDSS) has proven a powerful tool for identifying new lens candidates, although high angular resolution HST observations are essential for confirming those candidates as genuine gravitational lensing systems (see Program GO 10886). ... Past weeks: . ...

Image credit: Michael Nolan, Arecibo Observatory. These radar images of near-Earth asteroid 2001 SN263 were obtained on 2008 Feb 12 and 13. ... Image from Feb 12 . ... First near-Earth triple asteroid discovered by Arecibo Observatory . ... was discovered this week by astronomers at the sensitive radar telescope at Cornell University?s Arecibo Observatory in Puerto Rico. ... For example, Arecibo has discovered more than half of the near-Earth binary asteroid systems discovered since 1999. ...

... Bad Astronomy . ... Bitesize Astronomy . ... Bad Astro Store . ... Slacker Astronomy . ... Keep Bad Astronomy close to your heart, and help make me filthy rich. ... Life Under the Moon . ... Seeing Jupiter's Moons . ... Time Zones and the Spherical Earth . A Companion to the Earth? ... December 19, 1999) . ... Big Moon, Little Moon . ... How Big is the Moon? ... 14, 2000) . ... 2008 Phil Plait. ... Subscribe to the Bad Astronomy Newsletter! Talk about Bad Astronomy on the BA Bulletin Board! ...

Lectures . ... Home Lectures Lecture Series 2010-2011 Lecture Series 2010-2011 ? Greening the Earth Using Space Resources? by Greg Matloff . ... Lecture Series 2010-2011 . ... Beyond New York City . ... Observing Resources for Amateur Astronomers - Part 1: Beginning Observers . ... A History of the First Forty Years of the Amateur Astronomers Association . ... Amateur Astronomers Medal . ... 2016 Amateur Astronomers Association of New York Designed by Press Customizr Powered by . ...

... Asteroid . ... In case you didn't hear about it, which you probably didn't: On Jan. 7, an asteroid 1,000 feet across -- nearly three times the current diameter of Marlon Brando -- barely missed the Earth, which is most likely your planet of residence. ... What if this asteroid had hit the Earth? ... As it happens, the American Astronomical Society was holding a conference in Washington AT THE VERY SAME TIME as the asteroid nearly hit the Earth. ...

... The Round Earth . ... Aristarchus around 270 BC derived the Moon's distance from the duration of a lunar eclipse (Hipparchus later found an independent method). ... Let R be the radius of that circle and T the time it takes the Moon to go around once, about one month. ... Viewed from Earth, a "new Moon" (occuring between the time a thin crescent is last seen before sunrise and the time one is seen shortly after sunset) happens when the Moon in its apparent motion around the sky overtakes the Sun. ...

... This year's eclipse is unique in duration. ... Although, at the present time, there are 6 solar observatories belonging to leading space agencies in orbit around the Earth, the eclipse of 22 July, 2009, will only be seen by two of them: the Russian CORONAS-PHOTON satellite equipped with TESIS telescopes and Japan's HINODE satellite fitted with an XRT space telescope. ... TESIS will be the first of the two devices (and the very first on Earth) to witness the solar eclipse. ...

... The First (Experimental) International Astronomy Olympiad . The following olympic problems were proposed for the participants on the theoretical part: Grades 8-10 . ... Why is it sometimes better to use a small telescope in orbit around the Earth than it is to use a large telescope on a mountain top? ... What will an observer looking to the Moon through the telescope see? ... Paper with a drown circle and table of maximal elongations of Mercury and Venus had been done for participants. ...

... Satellite data ] . ... The SCANOR system provides receiving and processing of the Earth-surface pictures made in visible and infra-red bands and transferred by satellites of the NOAA polar orbiter series (in the HRPT mode). ... The SCANOR system includes the desktop receiving device connected to an IBM AT 386 type computer, and the parabolic antenna with the guiding mechanism. The SCANOR system possesses the state-of-art software providing registration and processing of the received data. ...