Here is where I admit I have never taken Geology or Organic Chemistry. This is my third time coming to LPSC and each time I come I learn there are more minerals yet to learn.
Today I spent my morning sitting in on sessions involving the new data coming down from the Lunar Missions Kaguya, Chang’e-1 and Chandrayaan-1. I’ll be doing the same this afternoon, and right now I’m sitting in a session on “What does the community want in future Moon Missions?”
The first thing I personally learned is I need to learn what more minerals mean and why they matter on the moon. To this end, I have received the following book recommendations: The Lunar Source Book, and New Views on the Moon. I will be beginning for my university to get both as soon as I get home.
Trying to figure out minerals was (and is) an important part of today because so much of the data coming back from the money is tracing out the composition of the moon in a variety of orbiting spectrometers and spectral imagers. In English, there are now instruments orbiting the moon that can separate out the light from different atoms and molecules to study their relative abundances and pinpoint their locations.
The first of these new spectrometers discussed today was the CIXS X-Ray Spectrometer on Chandrayaan-1, and Indian mission that is currently exploring the moon. This little camera (and really, anything that gets launched is probably little), is able to measure the abundances of rock-forming elements like Magnesium, Aluminum, Silicon, Calcium, Titanium, and Iron. Many of these minerals are things that are also useful for building and for life. While the instrument, like all X-Ray telescopes, has bad resolution, it gets great data. It’s resolution is about 25km. To work, it needs the sun to give of X-Rays (something that is normal when the sun is active), so the X-Rays can interact with the lunar surface and get re-emitted up to the detector. Unfortunately, the Sun refuses to be active. A few wimpy flares have allowed instrument testing, and Mg / Al / Si have all been detected. It still annoying not to be able to use the instrument to its fullest potential due to a lack of solar x-rays. This was not expected when this and other X-Ray instruments were launched. Scientists using the KAGUYA X-Ray spectrometer are having similar lack of data issues, thanks to the Sun’s lack of sun spots and related flares.
Luckily, NASA’s Moon Mineral Mapper (M^3) doesn’t need anything to work other then itself. This is to me the neatest flying instrument. Also mounted on Chandrayaan-1, it has a 140 meter per pixel resolution and a 40 km wide field of view. As it scans across the lunar surface, it simultaneously gathers data across a wide range of IR to visible wavelengths. This data can we used to trace out where different minerals exist on the moon (see image above – rainbows are spectral data). For instance, in work presented by C.M. Peters, images cutting across the Orientale Basin show differences in the geology of different places. Working from outside the basin (the Hevelius Formation) in to the Mare Basalts (lava inside the basin), they find the surface composition changes from Feldspathic breccias (Feldspar is a rock that crystallizes from magma) to shocked Anorthosite (a type of feldspar that makes up the light areas of the moon), to unshocked crystalline anorthosite, to high Calcium pyroxene (a rock made of silicate minerals) and pyroclastic (volcanic) rocks in the center. (Do you see why I decided I need to learn more about minerals?)
Work like this, and like that presented by R.O. Green, show the potential this instrument has to allow us to understand the surface of the moon in new details. This data for the first time allows us to carefully map the geophysics as well as the morphology (Craters and volcanoes, etc). Also working on the problem of composition is the SELENE SP abd GRS on KAGUYA.
In addition, other mission instruments have been working to measure gravitational pull as a function of position (and thus the density distribution of lunar materials), the radiation environment around the moon, the distribution of magnetic materials, and even to make temperature maps (where it is cold, there is the potential for volatiles like Oxygen.
Between now and next year I need to learn mineralogy…