LCROSS May 2009 Campaign
Although not yet formally announced as part of the NASA LCROSS Ground-based Observation Campaigns, Drs. Wooden and Kelley have reserved the 2009 May 6 -- 04:00 to 09:59 UT time slot on the IRTF telescope in Hawaii for "project 118", which has formerly been a code name for LCROSS practice.
The times mentioned for May observing run suggest that photos will be taken from the IRTF site starting at on before sunset.
The following diagrams, generated with the LTVT Earth Viewer, shows the position of the Moon relative to the Earth, and the location of the night-day terminator on Earth at the start and end of the run. At the beginning, the Moon should be simultaneously visible from much of North and South America; and at the end, from Australia.
(click on the thumbnails to see full-sized LTVT screenshots)
| **2009 May 06** | |
| **Start: 04:00 UT** | **End: 09:59 UT** |
| [](http://ltvt.wikispaces.com/file/detail/LCROSS_2009May06_0400UT_EarthView.jpg) | [](http://ltvt.wikispaces.com/file/detail/LCROSS_2009May06_0959UT_EarthView.jpg) |
The red and blue lines are the terminator on the Earth (as seen from the Moon).
This aerial view from over the Moon's north pole plots several potential LCROSS target locations on a recent, and presumbably highly accurate, topographic map published by the Kaguya scientists in the February 13, 2009 issue of Science magazine.
An observer looking square to the limb will see the targets disposed left to the right in the manner shown.
The simulation on the left was created using LTVT to remap an image by American amateur Tom Bash on March 8, 2009 at 04:25 UT. It was taken with similar lighting (Sun's colongitude = 50.2° and latitude = +1.0°), but with much less libration in latitude (+0.3°). As a result of the smaller libration in latitude, a substantial part of the northern region that will be seen on May 6th was not visible on March 8th, and is represented in the simulation by the black and blue areas.
| [](http://ltvt.wikispaces.com/file/detail/LCROSS_2009May06_0700UT_TargetLocations_TomBashPhoto.JPG) | [](http://ltvt.wikispaces.com/file/detail/IRTF_2009May06_0700UT_AstronoMinsk_HalfScale_annotated.JPG) |
The simulation on the right is painted using a full disk mosaic taken by the AstronoMinsk imagers on April 06, 2009 at 18:10 UT. The original libration in latitude was stronger than in the left-hand simulation, so there is less missing areas.
The letters indicate where the LCROSS targets (identified in the previous screenshot) would appear as seen from Earth at the time of the IRTF observations. The Moon is oriented as it would appear in an equatorially mounted telescope (celestial north up), and the pixel scale is half that of the IRTF slit jaw viewing camera.
At the midpoint of the LCROSS practice run on May 6, 2009 (at 07:00 UT), the Sun will be at a longitude of 39.2°E (colongitude 50.8°) and a latitude of +1.5°. The librations as seen from Hawaii will be +5.4° in longitude and +6.4° in latitude.
The following list gives dates and times from January 2000 through January 2010 on which similar conditions could be observed. It was prepared with a special version of the LTVT Libration Tabulator, searching for similar colongitudes (rather than for sun angles at a particular feature, as it normally does). The list consists of a series of start and end lines defining the intervals in which the colongitude was within ±10° of the LCROSS value simultaneous with the Moon's north pole being tipped toward Earth (as seen by a geocentric observer).
Times when the Sun's latitude (as well as its longitude/colongitude) is close to the LCROSS value will most resemble the lighting on May 6th (ones with a higher solar latitude -- the lunar "summer" will show more light on the poles, while ones with a lower latitude will show more features in shadow). Those with a libration in latitude similar to the LCROSS value will most closely resemble the geometry of the May 6th observations.
- LCROSS_2009May06_SimilarDates.txt 9 kb; rev. 8 Mar 2009 <-- click to view
This page has been edited 6 times. The last modification was made by - 
JimMosher on May 3, 2009 9:24 pm