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Observe or Image the Moon for NASA

Steve Nelson


Many of us have observed the Moon and tried to take pictures or look at an extreme libration (tilting) that shows areas not usually seen from Earth. Dave North has always impressed me as the SJAA’s local loony expert. NASA is planning to crash a rocket into either the north or south pole area of the moon to look for traces of water. These observations are being supported by amateurs. There were contributions by several California astronomers in early December. Turns out I assisted the NASA AMES astronomer on one of her first research runs - when she was an undergraduate at UCSC in the early 1980’s. So keep posted on how things went on the website at the end of the article.

Excerpts from “LCROSS Public Observation Campaign Program Overview”

NASA’s Lunar Crater Observation and Sensing Satellite (LCROSS) Observation Campaign is seeking assistance from amateurs to develop a library of digital images of the lunar poles under varying phase and librations.

With a scheduled launch date as early as Apr. 24, 2009, the current plan is to impact the North Pole during the August-September time frame. If the target pole changes to the South Pole, Faustini crater becomes a favorable candidate crater for the LCROSS impacts. The floor of Faustini is believed to be older and probably possesses a fine-grained regolith (soil) that is more easily lofted into sunlight as opposed to a rocky-bottomed crater floor.

To prepare for the LCROSS impacts of a permanently shadowed crater, Dr. Diane Wooden of NASA’s Ames research Center is developing targeting protocols for ...IRTF atop Mauna Kea on the Big Island of Hawaii. ...

To ensure that the scattered light of the ejecta cloud enters the spectrometer’s entrance slit, the positioning of the telescope needs accurate to about 0.5 arc seconds. Most moderate to large telescopes have positioning uncertainties larger than this and rely on nearby guide stars to improve their pointing accuracies. However, for the moon, guide stars are not practical. Instead, Wooden and her colleagues need to point to recognizable craters near the poles and offset to the position of the impacts.

During the months leading up to the launch, amateur astronomers are encouraged to image the north and south poles of the moon. The goal is to obtain images that determine the scale of recognizable features observed in the wider field of view on amateur telescopes when compared with the higher spatial resolution near-infrared IRTF images. A secondary goal is to compare the dynamic range of images that allow the verification of detection of subtle variations in topography and albedo. This exercise also may help amateurs to prepare for obtaining images of the impact plumes. The impact plumes will occur in shadowed regions, but these shadowed regions likely will be adjacent to lit regions The coordinates for preferred locations for LCROSS impacts within permanently shadowed craters, as of October 2008, are given below. Crater A and F are in the north polar region and Faustini and Shoemaker are in the south polar region.

Crater A: 84.45 N, 62.2 E Crater F: 86.2 N, 38.4 EFaustini: -87.5 (S), 83.1 E Shoemaker: -88.3 (S), 43.4 E ...

Amateur astronomers have the opportunity to create a useful reference imaging data set for the LCROSS impact. They can be helpful in the development of an amateur astronomer atlas of the lunar poles at different lighting and libration conditions. Images taken under different phases produce subtle shifts in crater shadows that affect determination of “crater centers” in images. This can affect the determinations in the offsets between these reference craters and a target crater. Furthermore, images taken during phases on the opposite side of full moon may reveal subtle features that are useful in refining the pointing accuracy.

The message goes on to tell the details of reporting observations and downloading images.

For more information about the LCROSS Observation Campaign, visit:

Amateur discussion at http:/ and you can image cashcraft_20081208127etseq2.jpg from the files for that group.


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