LunarScience

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During the first decades of the Moon's exploration, the Moon race, the largest part of scientific payloads and instruments were used to assess if the lunar environment could support humans and under which conditions. Most instruments were cameras, video of photographic, mapping the surface of the Moon from distance to find suitable landing sites, taking close-up imagery just before crashing on the Moon, or landers taking photographs of the lunar dust. Sample returns were also the most efficient way of studying the lunar regolith. In the past two decades, real science was conducted on the moon or around it, and this page lists the experiments that have taken place since 1950.

Soon, the first Google Lunax X-Prize (GLXP) teams shall land on the Moon and will probably increase this list a lot. One of the teams, Part-time Scientists from Germany, has made a call for payloads, cubesat-sized science packages that will land on the moon and return data to earth. The first goal of this page is to have a rough idea of what can be done with minor monetary investment, while still being useful, and possibly answer the call for payload.

Science with direct measurements taken of or from the surface of the Moon

From lunar orbit or intersecting trajectory

This section is incomplete

Gamma-ray spectrometry can be used from orbit to map the surface distribution of an element. The surface is continuously bombarded by cosmic rays, which make it emit gamma rays, then measured by the spectrometer. An example use was the mapping of KREEP distribution by the Lunar Prospector spacecraft.

Micrometeroid characterisation and detection by first orbiters.

Chang'e 1 and 2 had stereo cameras, laser altimeter, imaging spectrometer in visible and near-IR spectrum, Gamma and X-ray spectrometers, microwave radiometer for ground penetration up to 30m, and high energy particle and solar wind detectors. That was the first microwave (radar) mapping of the Moon.

The electromagnetic environment was also studied from orbit, by Chandrayaan-1, Lunar Prospector and LADEE. Chandrayaan-1 spacecraft mapped a "mini-magnetosphere" at the Crisium antipode on the moon's far side, using its Sub-keV Atom Reflecting Analyzer (SARA) instrument. Lunar Prospector spacecraft detected changes in the lunar nightside voltage during magnetotail crossings. LADEE has probably done more about magnetic field, to be completed.

From the surface, of the surface

X-ray spectrometers provide data very easy to interpret to obtain qualitative information about the elemental composition of a material. Matching data with well-known sample measurements or even standard spectra can lead to quantitative results. The main issue with such devices is producing X-rays, or other sources of energy that will make target elements radiate at X-ray levels of energy.

Infrared spectrometry can similarly inform about molecular composition.

This section is incomplete

In 2013, the YuTu rover from the Chinese mission Chang'e 3 carried three instruments: an alpha particle X-ray spectrometer (APXS) described in this paper (PDF) and an infrared spectrometer, both used to analyse the composition of soil or rocks on the surface; a couple of stereo cameras for collision avoidance and trajectory planning. The APXS sensor was the only instrument at the end of the robotic arm. The sensor's head was quite small and had a mass of only 752g. It also comprised a radio-isotope heater unit, to survive the lunar night, adding 390g. The APXS could also be used as a range sensor, measuring the X-ray count rate. The first two spectra can be found in the PDF linked above. There was also a part of the instrument in the rover, not in the arm, the total mass is unknown. Details and pictures of the device can be seen here.

There is a mention of a microwave sonar underneath the YuTu rover here, but not on the wikipedia page.

From the surface, of the rest of the universe

This section is incomplete

Lunar Ultraviolet Telescope (LUT). In 1972 Apollo 16 brought a 76mm far-UV telescope and in 2013 the Chang'e 3 lander had a 150mm near-UV telescope onboard. Lunar telescopes allow for long term monitoring of a target, because the moon has a low rotation rate, and with no UV filtering as from Earth atmosphere. Construction details and pictres can be found here, instruments section.

In 2013, the Chinese lander Chang'e 3 had an extreme ultraviolet camera whose purpose was to study the plasmasphere of the Earth and its variation with solar activity. The camera has a 15 degrees field of view. Details can be found here, instruments section.

What we know about the lunar environment

This section is incomplete

Topography of the Moon

Atmosphere

Regolith

Radiation

Magnetic field

Main article

Gravity map