Archive for October, 2012
On 12 October 2012, 5:30 UTC, an asteroid 2012 TC4 (which I discussed earlier) made a close approach at 95 000 km from Earth. Its photometric observations were conducted at out observatory 24 hours before the closest approach. During the observations, the asteroid got closer to our planet from 583 400 to 508 600 kilometers. Accuired data allowed to estimate its rotational period, which is 12.2 minutes. More detailed data, as well as the magnitude graph, will be published in the Minor Planet Bulletin. Fast rotation of such small cosmic bodies that come close to Earth is common, and serves as proof of their origin from collisions. I should note that the period of 12.2 minutes isn’t the shortest among asteroids observed at ISON-NM observatory. For example, rotation period of another asteroid – 2012 KP24 is just 2.5 minutes! Absolute record at the moment belongs to the asteroid 2010 TD54, it makes a full rotation in just 42 seconds!
The analysis of evolution of the orbit of asteroid 2012 TC4 during its close approach to Earth shows that its orbit was affected by the gravitational influence of the Earth-Moon system. In the XY plane (in this case the ecliptic plane), the asteroid’s orbit was deflected by ~13 degrees from its original direction. The orbital period of 2012 TC4 around the Sun increased by 20%, from 1.45 to 1.74 years. The graph below shows this. The next close approach of this asteroid with Earth will happen in 5 years.
Translation by Maksim Kakitsev.
According to Lance Benner, a member of the radar team, later of this week should be held radar imaging of recently discovered asteroid 2012 TC4, which will be pass on October 12 at distance about 97,000 km from the Earth. Currently required astrometric and photometric support observations by ground-based telescopes.
A few hours the Earth will pass close to discovered two days ago an asteroid 2012 TV, and now we expect even closer flyby of asteroid, discovered by an US survey Pan-STARRS. Object that has the temporary designation P104imJ was discovered on October 4. Within 8 days, on October 12 (4:45 UT), the asteroid will flyby at least 97,000 km from the Earth. According to preliminary data, the size of the object can be from 15 to 30 meters.
Very interesting the lead time for discovering of such objects. Amateur, 40-cm telescope, was discovered larger object in just 2 days before it’s close approach, while powerful, professional 1.8-meter telescope, discovered the object of more than a week before it’s close approach to our planet.
Tomorrow, at 19:03 Moscow time, a Near-Earth asteroid will make a close approach. The asteroid was discovered at the privately owned Tenagra Observatory less than 24 hours ago. Currently, the object is still being confirmed by the Minor Planet Center and has been given temporary designation TCT501. The asteroid should pass at 256 500 km from Earth, which is inside the lunar orbit. Weather permitting, tomorrow we will conduct photometric observations of this object. This asteroid is estimated to be 25-50 meters in diameter.
Translation by Maksim Kakitsev.