Archive for October, 2010

Recovery of a Jovian Trojan 2010 OY75

A new interesting object was discovered during the survey of October 15th. From our measurements of the first night, it was proposed that the object might be gravitationally bound to the largest planet in the solar system – Jupiter. The decision was made to continue observing the object iJTA033. Measurements obtained the second night, supported the hypothesis that the new object was located beyond the main asteroid belt. The observations of the 17th of October removed all doubt – the object was gravitationally bound to Jupiter. Since a temporary designation had not yet been obtained, I sent a letter to the director of the MPC, Timothy Spar. Within a few hours our observations were tied to an object discovered by the space telescope WISE on June 26, 2010. After two nights of observations the designation 2010 OY75 was given to an asteroid recovered by the observatory ISON-NM after 2.5 months.

The precision of the orbit of 2010 OY75 was significantly improved – it actually did belong to a rather rare family of asteroids – Jovian Trojans, located at the L4 point. At the moment 4525 asteroids of the family are known, 2792 of them are at the L4 point (“Greeks”), and the remaining 1733 – are at the L5 point (“Trojans”).

Near-Earth asteroid 2010 RN80 – one month after discovery

A month has passed since the discovery of our first near-Earth asteroid – 2010 RN80. In 30 days we have received 164 observations from 22 observatories around the world. As a result we have a sufficiently reliable orbit with the parameter U equal to 5. Overall, the first quality analysis of the asteroid ephemerides substantiates that the object has not come close to the Earth since the beginning of the era of CCD observations. A close approach to the Earth occurred on 5 Oct 1983;  that approach was closer than this year’s – the asteroid passed at a distance of 0.09 a.u. This year’s passage will be October 18th. Minimum distance of 2010 RN80 wil be at 08:34:38.50 +/- 8 seconds (UT).  At that time it will be 16.668 million km. away (0.1114 a.u.).

In these days the asteroid’s brightness will be at maximum, on the order of mag. 17, a little brighter than the calculated value. By the way, the estimate of the absolute magnitude of the asteroid (H) during this month changed from 20.4 to 20.1. Along with that, the estimate of the diameter of the body increased from 260 to 570 meters. Its size and the fortunate relative positions of the asteroid and Earth allow for observing it in small telescopes until February of 2011. The next close approach to the Earth, although not as close (the distance will be 0.17 a.u.), will be in 2037 (with a certainty of 58%). Its estimated brightness will be magnitude 18.5 to 19.

But most interestingly, 2010 RN80 turns out to be a near-Mars asteroid! With a high probability we can say that our object more frequently comes closer to the Red planet. In the last 30 years the asteroid passed close to Mars 7 Jul 1987 (+/- 12 days TCA3Sg = 17652) at a distance similar to the current approach to the Earth, of 0.1132 a.u. But the closest approach will be Mar. 6, 2105 (+/- 16 days, TCA3Sg = 23173); the asteroid will pass by Mars at a distance of only 0.046 a.u.! The next encounter with Mars will be in 2136.

Although between Oct. 15 and Nov. 1, 2010 RN80 will cross the Milky Way, observing conditions will remain excellent. It will climb higher in the northern sky. Nov. 20, the asteroid will be less than 4 degrees from Polaris. I hope that over the next several months, the orbit of our asteroid will be refined and based on all the observations, in February of 2011 the final analysys of the evolution of its orbit will be published. And we will continue the search for new and interesting Solar System objects!

Binary asteroids – another interesting lecture in the SETI institute

Sorry, this entry is only available in Russian.

October 2010
« Sep   Nov »