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| Titel |
Design constraints affecting magnetometers for Jupiter and Saturn missions |
| VerfasserIn |
H. O'Brien, P. Brown, C. Carr, M. Dougherty, T. Oddy, T. Beek |
| Konferenz |
EGU General Assembly 2009
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 11 (2009) |
| Datensatznummer |
250030183
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| Zusammenfassung |
| The magnetic field is a fundamental physical parameter, vital for the study of processes in
interplanetary space and at giant magnetospheres such as those found at Jupiter and
Saturn. Â It can provide information on induced or internal magnetic signatures at
planetary bodies; resolve the planetary rotation rate, plasma transport etc., and thus
its accurate measurement at multiple points in space and time is crucial in space
missions.  Â
Proposals currently being considered to the Jupiter and Saturn systems offer the
opportunity of taking multi-point magnetic field measurements with sensors located on
orbiters as well as landers and balloon platforms. These missions pose considerable
engineering challenges for payload developers. In addition to contending with extremely
low mass and power constraints as well as the expected intense radiation fluence, exposed
instrumentation (such as magnetometer sensors) must be capable of successful operation at
low temperatures, estimated at below 110K in the case of a Titan or Europa descent. Whilst
orbiter and balloon based instruments may be able to use heaters to maintain operating
temperatures of boom mounted sensors, power is unlikely to be available to heat lander based
instruments.
For the DC vector magnetic field measurement the traditional space magnetometer sensor
of choice, the fluxgate, is mass limited according to its noise performance (typical mass of the
order 200g) and generally operates at working temperatures of much higher than 110K
employing a heater element where necessary. It is therefore worthwhile to ask at the
mission concept stage if there are other technologies for DC field measurement that
can mitigate either the low mass constraints or permit heater free operation while
delivering science grade capability on the timescales of future Jupiter and Saturn
missions.
We describe two technology regimes capable of delivering low resource magnetometers
and how they may be targeted to orbiter, balloon and lander applications on the required
timescales. The first is based on a traditional fluxgate sensor but optimised for low
temperature operation and the second is a novel design based on a magneto-resistive sensing
element.Â
Note: if a decision has been made at the ESA level between the mission proposals
targeted at Saturn or Jupiter, then this submission will concentrate on the chosen mission. |
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