Phase II Final Report - NASA's Institute for Advanced Concepts

Chapter 1.0 Introduction
1.3 Mission
craters’ magnetic signatures, can lead to a greater understanding of the early history of magnetism
on Mars. Also, by identify young craters in older terrain and mapping the magnetic fields
around these craters, information relevant to the thermal evolution of the planet can be obtained.
The history of Mars’ magnetic field may be an important link for understanding the radiation
environment due to the early sun's solar wind.
From previous scientific investigation, it is know that the magnetism of Mars varies greatly over
the planet’s surface. It is very highly magnetized at certain locations (an order of magnitude
greater than the magnetic field strength on Earth, and at altitudes an order of magnitude higher
than on Earth, greater than 1,500 nT at 100 km altitude, and greater than 250 nT at 400 km altitude),
and weakly magnetized at others. The locations of the strong magnetic fields correspond
with some of the older and highly cratered areas of Mars.
Presently there is no active mechanism for forming a uniform magnetic field (as on Earth).
Because of this lack of a planetary magnetic field, it is much easier to measure the crustal magnetization
directly. This crustal magnetization can exceed several Gauss (200,000 nT). The magnetic
landscape of Mars was first discovered by the Mars Global Surveyor spacecraft. This
spacecraft measured many large scale, highly magnetic locations on the surface of Mars, many
extending over hundreds of kilometers. However, due to the distance from the surface, small
scale variations in the magnetic fields, which are believed to exist could not be discerned. The
Entomopter can be used to investigate these magnetic field regions and provide high resolution
data on the magnetic field strength variations within these regions. An example of the differences
between the magnetic fields on Mars and Earth are shown in Figure 1-14.
Earth Magnetic Field
Mars Magnetic Field
Figure 1-14: Magnetic Field Shape on Earth and Mars
The magnetic field mapping done by the Entomopter would enable a greater understanding of
the crustal magnetism on Mars. For this to be accomplished, it would require that measurements
of the magnetic field be performed with enough spatial resolution to relate magnetism to specific
geologic features and structures. With the Entomopter, the spatial resolution on these measurements
would be less than 1 m, orders of magnitude greater than what is achievable from orbit.
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