... 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 . ...

... Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2011 October 22 . Jupiter Near Opposition . ... Explanation: On October 29 (UT) , Jupiter, the solar system's largest planet , will be at opposition, opposite the Sun in planet Earth's sky, shining brightly and rising as the Sun sets. ... About APOD | ... NASA Official: Phillip Newman Specific rights apply . ...

... Planets . ... Stars . Exoplanets . ... Most exoplanets so far discovered fall into the category of тАШhot JupitersтАЩ, these are giant planets orbiting very close to their parent star. ... Note that we have discovered so many hot Jupiters because they are the easiest type of planet to find, they are not necessarily particularly common in the galaxy. ... Subsequently several similar hot and€а fuzzy worlds have been discovered the same way, proving this that this planet is not a one-off oddball. ...

... 14.05.2015 . ... Credit Copyright: Damian Peach / SEN Explanation: In this sharp snapshot, the Solar System's largest moon Ganymede poses next to Jupiter, the largest planet. Captured on March 10 with a small telescope from our fair planet Earth, the scene also includes Jupiter's Great Red Spot, the Solar System's largest storm. In fact, Ganymede is about 5,260 kilometers in diameter. ... Though its been shrinking lately , the Great Red Spot's diameter is still around 16,500 kilometers. ...

... Earth is the tiny spot between Jupiter and the Sun). ... Distance Radius Mass Name Orbits (000 km) (km) (kg) --------- ------- -------- ------- ------- Sun 697000 1.99e30 Jupiter Sun 778000 71492 1.90e27 Saturn Sun 1429000 60268 5.69e26 Uranus Sun 2870990 25559 8.69e25 * Neptune Sun 4504300 24764 1.02e26 * Earth Sun 149600 6378 5.98e24 Venus Sun 108200 6052 4.87e24 Mars Sun 227940 3398 6.42e23 Ganymede Jupiter 1070 2631 1.48e23 + Titan ... Extrema .. ...

Jupiter is the largest of the nine planets, more than 10 times the diameter of Earth and more than 300 times its mass. ... The mean density of Earth is 5.245 times that of water. The pull of gravity on Jupiter at the top of the clouds at the equator is 2.4 times as great as gravity's pull at the surface of Earth at the equator. ... It is tipped about 11њ to Jupiter's axis of rotation, similar to Earth's, but it is also offset from the center of Jupiter by about 10,000 kilometers (6,200 miles). ...

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. ...

... 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.. ...

... 8, ``Celestial Mechanics'', 2002 Formation and migration of trans -- Neptunian objects S. I. Ipatov 1;2 1 Institute of Applied Mathematics, Moscow, Russia 2 NASA/GSFC, Greenbelt, USA We support the Eneev's idea [1] that the largest (with diameter d?100 km) trans ­ Neptunian objects ( TNOs ) moving now in not very eccentric orbits ... The total amount of water delivered to the Earth during the formation of the giant planets was about the mass of water in the Earth's oceans. ...

What will happen when the fragments hit Jupiter? ... All the fragments will enter Jupiter's atmosphere at an angle of 42 degrees from the vertical and impact near a latitude of 44 degrees south, but on the back side of the planet as seen from Earth (about 10 degrees in longitude behind the edge of Jupiter, as seen from Earth). ... Any body moving through an atmosphere is slowed by atmospheric drag, by having to push the molecules of that atmosphere out of the way. ...

... Science Users Information Future Facilities and Development E-ELT jump to navigation jump to content . ... Observing with ESO Telescopes . ... In December 2012 ESO Council fully approved the E-ELT Programme ( more , more , even more , still more ). ... In December 2014 ESO Council approved the construction of the E-ELT in two phases, and authorised spending on Phase 1 . ... 15 Jan 2012] Announcement of the E-ELT Workshop "Shaping E-ELT Science and Instrumentation" , 25 February 01 March 2013 . ...

... 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. ...

... About meteorites . ... Meteoritic data . Impact Crater Smerdyachee . ... Based on Smerdyachee's depth, near circularity, and its mounded wall, and analysis by N.A. Fillin of nearby Roshal, Russia, the Estonian scientists Yu.V. Krestlane and K.H. Mella proposed in 1987 that Smerdyachee Lake is a meteorite crater. ... In 2002, the Laboratory of Meteoritics of the Vernadsky Institute of Geochemistry and Analytical Chemistry of the Russian Academy of Sciences explored this mysterious lake. ...

... Tonight's Sky . ... The Magazine . ... Observing . ... 50 Weirdest Objects . ... Supernova showered Earth with radioactive debris . ... Gravitational wave search provides insights into galaxy evolution and mergers . ... The double star 54 Leonis, spiral galaxy NGC 3198, and emission nebula NGC 3199 . ... Observing springtime deep-sky objects with a large telescope . ... near earth objects . ... Receive news, sky-event information, observing tips, and more from Astronomy's weekly email newsletter. ...

T he Siding Spring Survey (SSS) is a Near-Earth Object search program that utilises the 0.5-m Uppsala Schmidt Telescope at Siding Spring Observatory, N.S.W., Australia. ... The mission of the Siding Spring Survey is to contribute to the inventory of near-earth objects (NEOs), or more specifically, the potentially hazardous asteroids (PHAs) and comets (PHOs) that may pose a threat of impact and thus harm to civilization. ... Based on the CSS Mission page . ... Siding Spring Survey Main Page . ...

Venus under the clouds. ... Venus is the second from the Sun and the nearest to the Earth planet of solar system. ... As for Venus, it has the densest atmosphere, the smallest rotation around the axis and the least eccentricity of the orbit Venus is the only planet whose own rotation is opposite it’s rotation around the Sun. ... The radiolocation survey of Venus by the soviet station "Venera - 15" and "Venera - 16" brought out in 1984 in the planets satellite`s orbit shoued the tarces of long walls. ...

... Kepler is a mission designed to detect and characterize Earth-sized planets around solar-like stars. The sizes of the planets are determined from the decrease in light from a star that occurs during planetary transits, and the orbital period is determined from the repeatability of the transits. ... These goals are accomplished by continuously and simultaneously monitoring a single field of 140,000 stars for evidence of brightness changes caused by transits of Earth-sized or larger planets. ...

... A dynamo is created in a magnetic field by an electric circuit, part of which is moving relative to the rest (additional conditions must also be met). ... Furthermore, the plasma between them conducts electricity very well along its magnetic field lines, which act as if they were wires connecting Io and the planet (drawing). ... The drawing is not to scale. ... The Hubble Space Telescope , using its Wide Field and Planetary Camera 2, has been photographing auroras of the planet Jupiter. ...

The cold, dry, and stable air above the summits of the Antarctic plateau provides the best ground-based observing conditions from optical to sub-millimetre wavelengths to be found on the Earth. Pathfinder for an International Large Optical Telescope (PILOT) is a proposed 2 m telescope, to be built at Dome C in Antarctica, able to exploit these conditions for conducting astronomy at optical and infrared wavelengths. ... Australia Telescope National Facility . ...

The AstroGuide . ... AstroGuide | ... AstroGuide Listing . ... See many more Astronomy Listings by: Category or Alphabet . This project was established in mid-1998 to help coordinate, and provide a focal point for, the study of those comets and asteroids that can approach the Earth's orbit. ... Web Site . ... Unless otherwise specified, web site content Copyright 1994-2016 John Huggins All Rights Reserved . dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET" . are trademarks of John Huggins ...