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| Titel |
Nitrogen Ion TRacing Observatory (NITRO) concept: a possible mission for next ESA's M-class call |
| VerfasserIn |
Masatoshi Yamauchi, Iannis Dandouras, Nikolaos Paschalidis |
| Konferenz |
EGU General Assembly 2014
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 16 (2014) |
| Datensatznummer |
250089616
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| Publikation (Nr.) |
 EGU/EGU2014-3822.pdf |
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| Zusammenfassung |
| Nitrogen is a key element for life as an inevitable part of the amino acid and protein, and
its oxidation state (NH3 or N2 or NOX) in the ancient atmosphere is one of the
key factors that determine the difficulty in forming amino acid without biological
processes. Considering the fact that nitrogen molecule with triple chemical binding
is much more difficult to be desolved/ionized than oxygen molecule with double
chemical binding, and that dependence of the ion outflow from the ionosphere on the
geomagnetic activity is more drastic for cold nitrogen ion than cold oxygen ions, it is
important to understand the dynamic of N+ and N2+ at different solar conditions
as compared to oxygen dynamics or proton dynamics. However, nearly no such
observation exists at low energy less than keV, except very little observations for thermal
nitrogen.
One reason for lack of such measurement is difficulty in separating hot N+ from hot O+ even
with the modern instruments, causing past instruments on board magnetospheric missions not
targeting such separation but rather targeting higher temporal and spatial resolutions.
However, with recent improvement of mass-separating ion analyser, it is now most likely
possible to separate O+ and N+ by masking H+ and He++ and by limiting the angular
coverage to minimize the contamination. In this sense, the nitrogen study in the
magnetosphere requires a dedicated space mission.
At moment there are two options: (1) pioneering single spacecraft mission with minimum
instrumentation to detect hot nitrogen ions of missing energy range from 50 eV to 10 keV in
the past missions; and (2) multi-spacecraft mission to make a comprehensive understanding
of the dynamics of nitrogen ions in the magnetosphere. Here we present necessary spacecraft
and instrumentation for the second option because that will be fitted into the M-class
mission (450 MEUR) that European Space Agency most likely announces soon this
year.
The mission consists of three spacecraft, two mid-altitude satellites for in-situ measurement
with gradient information (by the second spacecraft), and one low-altitude satellite for
outward remote sensing to obtain line-of-sight integration information. Instrumentation for
such a mission also benefits studies on the inner magnetosphere, substorms, and basic plasma
physics such as ion energization. We welcome contributions for the model instrumentation
fitting into the mission particularly the optical ones toward the coming European M-class
announcement. The other ideas to detect the nitrogen ions and their dynamics are also very
welcome. |
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