... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . Asteroid 2010 SO16 and the Earth follow similar orbits around . the Sun. ... out a horseshoe shape in space, taking 175 years to go from . ... Asteroid 2010 SO16 takes 175 years to make the trip from one end of the horseshoe to the other. ... Currently, three other horseshoe companions of the Earth are known to exist but, unlike 2010 SO16, these linger for a few thousand years at most before moving on to different orbits. ...

... More on 51 Peg: . The discovery of a Jupiter--mass planet in orbit around the solar--type star 51Peg has been reported by Michel Mayor and Didier Queloz (Geneva Observatory) on October 6th at the 9th Cambridge workshop on "cool stars, stellar systems, and the sun" held at Florence (Italy). ... Recall that the measurements of radial velocity only yield v sin i which in turn gives us M sin i. For most values of i, sin i will be greater than 0.5 and this gives a mass estimate of 0.5 Jupiter masses. ...

... 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! ...

Astronomy Picture of the Day . Animation of Asteroids Passing Near Earth . ... The above time-lapse animation follows the orbit of the Earth around the Sun for two months in 2002 as numerous asteroids , also known as minor planets , approach and pass by. ... Although none of the plotted objects came inside the orbit of our Moon, our Solar System is filled with objects as small as bits of sand, usually left by a comet, that appear as meteors as they streak into the Earth's atmosphere every day. ...

... In addition to the planets and their satellites the solar system contains a large number of smaller but interesting objects. There are thousands of known asteroids and comets and undoubtedly many more unknown ones. ... There are also some asteroids whose orbits carry them closer to the Sun than the Earth (Aten, Icarus, Hephaistos). Most comets have highly elliptical orbits which spend most of their time in the outer reaches of the solar system with only brief passages close to the Sun. ...

... Comet Tutorial . ... On July 1, 1993 an image was taken with the Hubble Space Telescope (HST) that clearly shows at least 15 individual fragments in one image frame of the train. ... This made an accurate orbit (or orbits) difficult to determine; however, after numerous observations of the comet, astronmers determined that the comet had passed within 96,000 kilometers (60,000 miles) of the center of Jupiter or 25,000 kilometers (16,000 miles) from the cloud tops during the July 8, 1992, approach. ...

... The awsome spectacle of a brilliant comet, with its long ghostly tail streaming behind it, is a rare event. ... Only one other comet, Comet Halley, was seen so far from the Sun, giving scientists an opportunity to watch it as it slowly warmed up and sprouted a tail. ... Comets are the Rip Van Winkles of the solar system -- mini-worlds that have changed little during their 4.5-billion-year nap far from the Sun. ... Observing Comets . ... Once, comets inhabited the entire solar system. ...

Astronotes Armagh Planetarium's Stellar Blog! ... Moon . Planets . ... Monthly Sky Notes . ... February . ... The ringed planet will be quite bright, but unlike Jupiter it will not be the brightest point of light in the sky, this accolade will return to Sirius which is the brightest star in our night sky in the constellation of Canis Major. ... Seven days later on February 18, the Moon will be in its full Moon phase. ... Tweets that mention Wonders of the February Night Sky | ... Astronotes . ...

... Asteroid Introduction (This Page) . ... Asteroid Summary . Asteroids . Gaspra , Ida & Dactyl , Toutatis , Castalia , Vesta , Geographos, Mathilde . ... NEAR Spacecraft Homepage . Near-Earth Asteroid 3753 - Earth's Curious Companion . ... Then on October 1991 asteroid 951 Gaspra was visited by the Galileo spacecraft and became the first asteroid to have hi-resolution images taken of it. ... Both Gaspra and Ida are classified as S-type asteroids composed of metal-rich silicates. ... Gaspra . ...