Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Odyssey 2 : A mission toward Neptune and Triton to test General
  Relativity   Odyssey 2 will be proposed in December 2010 for the next call of M3 missions
for Cosmic Vision 2015-2025. This mission, under a Phase 0 study performed by
CNES, will aim at Neptune and Triton. Two sets of objectives will be pursued.
The first one is to perform a set of gravitation experiments at the Solar
System scale. Experimental tests of gravitation have always shown good
agreement with General Relativity. There are however drivers to continue
testing General Relativity, and to do so at the largest possible scales. From a
theoretical point of view, Einstein's theory of gravitation shows
inconsistencies with a quantum description of Nature and unified theories
predict deviations from General Relativity. From an observational point of
view, as long as dark matter and dark energy are not observed through other
means than their gravitational effects, they can be considered as a
manifestation of a modification of General Relativity at cosmic scales. The
scientific objectives are to: (i) test the gravitation law at the Solar System
scale; (ii) measure the Eddington parameter; and (iii) investigate the
navigation anomalies during fly-bys. To fulfil these objectives, the following
components are to be on board the spacecraft: (i) the Gravity Advanced Package
(GAP), which is an electrostatic accelerometer to which a rotating stage is
added; (ii) radio-science; (iii) laser ranging, to improve significantly the
measure of the Eddington parameter. The second set of objectives is to enhance
our knowledge of Neptune and Triton. Several instruments dedicated to
planetology are foreseen: camera, spectrometer, dust and particle detectors,
and magnetometer. Depending on the ones kept, the mission could provide
information on the gravity field, the atmosphere and the magnetosphere of the
two bodies as well as on the surface geology of Triton and on the nature of the
planetary rings around Neptune.

23
The categories of this paper are: solv-int
1
The categories of this paper are: cs
19
The categories of this paper are: eess
8
The categories of this paper are: hep-ex
32
The categories of this paper are: atom-ph
36
The categories of this paper are: cmp-lg
2
The categories of this paper are: math
14
The categories of this paper are: math-ph
37
The categories of this paper are: supr-con
10
The categories of this paper are: q-bio
20
The categories of this paper are: acc-phys
18
The categories of this paper are: econ
33
The categories of this paper are: plasm-ph
21
The categories of this paper are: adap-org
4
The categories of this paper are: cond-mat
7
The categories of this paper are: hep-th