Joe wrote:
This looks really good for us! Thanks, Joe
I have add a qualifier on this. Although the LCROSS impact dates and times are a report by a first-person LCROSS team member, the impact times are inconsistent with prior LCROSS statements. As the the Raupe blog analysis at http://lunarnetworks.blogspot.com/2009/05/moon-at-lcross-impact.html notes, at the May 21 press conference, an LCROSS team member stated that they were trying to time the impact when the Moon was over Keck (and the slit spectrograph at IRTF). This is what I have always understood was going to happen (that the impact will be timed to favor the big Hawaii observatories). This figure shows the sublunar position of the Moon at 10:30 UT and 13:30 UT on 10-8-2009: http://members.csolutions.net/fisherka/astronote/photos/20091009MoonPosFig1.... At 10:30 UT, the Moon is over New Mexico and only at about 46 degs alt at Hawaii. The Moon would transit Hawaii about 3:43 Hawaii time (13:43 UT) at a much higher local Hawaii altitude. For the Intermountain Time Zone, you really only have a two hour window between 10:30UT and 12:30UT before Intermountain astronomical twilight where the impact can be imaged at a better altitude in Hawaii but still be visible in the Intermountain west. Pacific coasters have another hour of darkness to work with. In short, I suspect and hope the actual impact date and time will firm up somewhere in this two hour window. At 12:30UT, the situtation will be reversed, the Moon will be at about 76 degrees over Hawaii and only about 45 degrees in alt in Utah. So again, like most LCROSS announcements, things are provision, may change before the impact and probably involve windows of opportunity several hours in duration. But, things are still looking much better for North Am observers, however, the impact date and time finally firms up. But it looks like the impact will be a sufficiently real thing for Utah to start dusting off my telescope for (or wiping the rain water off it given today's weather). -:) Clear Skies - Kurt