Lunar Reconnaissance Orbiter Camera

Predicting Imaging Conditions - The Temperature Model

Hi, my name is Prasun Mahanti and I am involved with temperature modeling for the LRO Narrow Angle Camera [NAC]. The NAC is a digital camera and uses semiconductor devices to take a picture similar to your own digital camera. As an example, when the NAC is looking at a mountain on the Moon, the image is recorded by a charge coupled device (CCD) instead of film. Semiconductors (here a CCD) are very temperature sensitive, so the noise characteristics of the returned image varies when the temperature goes up and down. Several of us in the LROC Science Operations Center therefore are tasked with forecasting the probable temperature of the NAC CCD a few days in advance. For a given temperature appropriate image acquisition commands can be sent to LRO for different positions around the Moon to insure the best-quality images.

My job is to build a thermal model using existing temperature records from the mission so far. The model is used to predict the future temperature of the NAC focal plane as the LRO takes images of the Moon. The fun part of this modeling is the uncertainty.  We do not know for sure, but we try our best to mathematically model a physical phenomena and eventually, get closer to the truth. Knowing the imaging conditions makes it possible for the LRO NAC to take a much better image. So far we have always been very close in our estimates!