Abstract
NASA designated Reiner Gamma (RG) as the landing site for the first
Payloads and Research Investigations on the Surface of the Moon (PRISM)
delivery (dubbed PRISM-1a). Reiner Gamma is home to a magnetic anomaly,
a region of magnetized crustal rocks. The RG magnetic anomaly is
co-located with the type example of a class of irregular
high-reflectance markings known as lunar swirls. RG is an ideal location
to study how local magnetic fields change the interaction of an airless
body with the solar wind, producing stand-off regions that are described
as mini-magnetospheres. The Lunar Vertex mission, selected by NASA for
PRISM-1a, has the following major goals: 1) Investigate the origin of
lunar magnetic anomalies; 2) Determine the structure of the
mini-magnetosphere that forms over the RG magnetic anomaly; 3)
Investigate the origin of lunar swirls; and 4) Evaluate the importance
of micrometeoroid bombardment vs. ion/electron exposure in the space
weathering of silicate regolith. The mission goals will be accomplished
by the following payload elements. The lander suite includes: The Vertex
Camera Array (VCA), a set of fixed-mounted cameras. VCA images will be
used to (a) survey landing site geology, and (b) perform photometric
modeling to yield information on regolith characteristics. The Vector
Magnetometer-Lander (VML) is a fluxgate magnetometer. VML will operate
during descent and once on the surface to measure the in-situ magnetic
field. Sophisticated gradiometry allows for separation of the natural
field from that of the lander. The Magnetic Anomaly Plasma Spectrometer
(MAPS) is a plasma analyzer that measures the energy, flux, and
direction of ions and electrons. The lander will deploy a rover that
conducts a traverse reaching ≥500 m distance, obtaining spatially
distributed measurements at locations outside the zone disturbed by the
lander rocket exhaust. The rover will carry two instruments: The Vector
Magnetometer-Rover (VMR) is an array of miniature COTS magnetometers to
measure the surface field. The Rover Multispectral Microscope (RMM) will
collect images in the wavelength range ~0.34–1.0 um.
RMM will reveal the composition, texture, and particle-size distribution
of the regolith.