Tuesday, 6 March 2007

2007 February notes: 2007 BD7, 2007 BZ48 and 2007 DA61

The first half of February was reasonably favourable with 8 nights used up to the 14th and 49 hours logged, while the last half of the month was very poor, with just 4 cloud interrupted hours logged over 3 nights.

Apollo object 2007 BD7 discovered on 23 Jan 2007 from Lowell was followed on four nights up to 6th Feb as it approached Earth, with it's phase angle reaching about 90 degrees on the last night. It was moving swiftly into evening twilight and with the phase angle continuing to increase and magnitude fading rapidly it was not seen again.

Another Apollo 2007 BZ48, discovered by the Mt. Lemmon Survey in January and making a close approach in February, was also observed on four nights, last seen on the morning of the 7th within hours of it passing Earth at 4.5 Lunar distances at a moderately fast 56"/minute.

The only object imaged from the NEO Confirmation Page in the last half of the month was 2007 DA61, during a half hour gap in the clouds on 25th Feb. This turned out to have a perihelion distance of 2.6 AU, in a highly elliptical orbit, elements available by early March giving P=134 years and indicating perihelion at the beginning of March 2007 (though these values may change somewhat as further positions are obtained). It appeared completely stellar in my images and is likely to be a Damocloid asteroid, but it is possible it might show some signs of outgassing with large instruments in the coming weeks.