Remote Sensing of the Moon and Planets

Professor Lucey's planetary science interests focus on the Moon and asteroids, but he has also conducted research and published papers on Mercury, Venus, and Mars. Dr. Lucey's lunar research has primarily exploited remote sensing data to understand the composition of the lunar crust and the surfaces of asteroids, and to improve the ability to derive quantitative information from remote sensing data of these objects.

For example, in collaboration with colleagues in Hawaii and Washington University at St. Louis, Dr. Lucey developed a method to derive the abundance of the elements iron (Fe) and titanium (Ti) from multispectral imaging of the Moon. He is currently working with scientists at Los Alamos National Laboratory to compare the measurements of Fe and Ti derived from the recent to the estimates he derived from multispectral imaging. This work has already resulted in the ability to map the abundance of the rare elements gadolinium and samarium on the Moon by comparing results from Dr. Lucey's Fe and Ti measurements with images of the Moon derived from Lunar Prospector's neutron spectrometer.

Dr. Lucey's spacecraft experience includes being a member of the science team on the Department of Defense/NASA joint mission to the Moon called Clementine and he still actively works on the data from this mission. He is also a Participating Scientist with the NASA Discovery Program Near-Earth Asteroid Rendezvous Mission.

Observations of the Moon in lunar eclipse

Dr. Lucey also conducts planetary astronomy and currently works on determining the thermal properties of the Moon by observing the lunar surface as it cools during lunar eclipses. Lunar eclipses occur when the Earth passes between the Moon and the Sun, so that the shadow of the Earth falls on the Moon. Because the Moon turns so slowly, the temperature of the surface of the Moon is near thermal equilibrium and is a strong function of the angle of the Sun (how far the Sun is above the lunar horizon) and to a lesser extent the brightness of the surface of the Moon (a bright part of the Moon will not absorb as much sunlight as a dark part and so will be somewhat cooler, though the entire surface of the Moon is by definition, cool, way cool). However, when the amount of sunlight changes very rapidly as it does during a lunar eclipse, the temperature of the surface cannot keep up with the rapid change. During a total eclipse when no sunlight falls on the Moon for a fairly long time, the surface cools off, and and different parts of the Moon cool off at different rates.

Areas covered with rocks tend to keep their heat (they have high thermal inertia). Areas covered with fine powder lose their heat very rapidly (they have low thermal inertia). So an image of the Moon in eclipse is very sensitive to the relative amount of rock and soil at the surface of the Moon. The relative amount of rock and soil at the surface of the Moon is partly governed by how long a portion of the Moon has been exposed to space. The light colored areas on the Moon are very ancient with surfaces at least 4.2 billion years old. They have been exposed to meteorite bombardment for such a long time that few rocks are left intact on the surface. Most of the rocks have been ground to fine powder. The dark colored parts of the Moon are actually covered by more recent lava flows which have many more rocks in their surfaces because they have not been ground up so thoroughly. In theory, we can compare the ages of different lava flows by comparing their thermal inertia (rock abundance). Some scientists think that some lava flows are very young (by lunar standards). We hope to determine if this idea is correct using infrared pictures of the Moon obtained in lunar eclipse.