In case anyone's looking for yet another reason to "take data", a few days ago the folks at Goldstone were planning radar observation of minor planet 2009 WV25 but found the its position was so poorly known they were not sure exactly where to point their equipment. So they sent out a request to the amateur community asking folks to find the little bugger and map its position. A number of us did so and today we received the following. So chalk this one up to yet another instance where amateurs helped the pros. patrick :) p.s. This kind of taking data (astrometry) is much easier than what I posted about a few days ago (photometry). On 02 Dec 2009, at 15:49, Lance Benner wrote:
Goldstone radar observations of near-Earth asteroid 2009 WV25 this afternoon have been successful. We got strong echoes within seconds and obtained a bandwidth consistent with expectations given the rotation state and estimated size of this object.
We haven't measured the size yet but are configuring to do so in the short time remaining on this, our only radar track to observe this asteroid.
Thank you very much to everyone who reported astrometry. We used everything that had been reported up though today's Daily Orbital Update (MPEC 2009-X03). Photometry reported in the last two days shrank the 3-sigma plane-of-sky pointing uncertainties from about 33 arcseconds to 5.6 arcseconds and were critical to our ability to point.
Prior to the radar observations, the 3-sigma time delay uncertainty was about 18000 microseconds (2700 km). After obtaining three Doppler measurements, we reduced the uncertainty to about 180 microseconds (27 km), an improvement by a factor of 100.