Outer Solar System (OSS)A Planetary and Fundamental Physics Mission to Neptune, Triton and KBO
B. Christophe on behalf of OSS Team
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OSS
Eddington’s Parameter at 10-7
Deep SpaceGravity at 10 pm/s2
NeptuneTriton
Kuiper Belt Object
Od
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Mis
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Mission to N
eptune, Triton and K
BO
Planetary PhysicsFundamental Physics
Inline with Fundamental Physics Roadmaps Advisory Group Report
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Deep Space Gravity Test
Accurate Navigation of S/CAccurate Navigation of S/C
Radio-Science
Laser-Science
PositioningPositioning
1-way or2-waysX+Ka band
VLBI
What is the S/C trajectory ?What is the S/C trajectory ?
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Laser Science: two concepts
One-way pulsed laser(proposed by E. Samain – OCA)
Two-ways continuous coherent laser(proposed by P. Wolf – SYRTE)
Clock
Spectral Filter
Linear Photo-
Detection
Coarse Timing (FPGA)
Res = 10 ns
Temporal Filter (x pseudo
random code)
Calculator
Fine Timing(Vernier)
Res = 10 ps
Frequency Synthesis
Telemetry
Laser pulse
Clock
Spectral Filter
Linear Photo-
Detection
Coarse Timing (FPGA)
Res = 10 ns
Temporal Filter (x pseudo
random code)
Calculator
Fine Timing(Vernier)
Res = 10 ps
Frequency Synthesis
Telemetry
Laser pulse
TESA TCL Terminal
PLL Laser
USO
100 MHzfrom ground
to ground
PBS
1064 nmMercury Ion JPL or Horace Syrte clock
Adaptative Optics on ground
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Deep Space Gravity Test
Accurate Navigation of S/CAccurate Navigation of S/C
Radio-Science
Laser-Science
PositioningPositioning
1-way or2-ways
Non Gravitational ForcesNon Gravitational Forces
DC Accelerometer< 10 pm/s2
X+Ka bandVLBI
Is S/C on a geodesic ?Is S/C on a geodesic ?
What is the S/C trajectory ?What is the S/C trajectory ?
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DC Accelerometer GAP
Noise of MicroSTAR
1.E-13
1.E-12
1.E-11
1.E-10
1.E-09
1.E-08
1.E-05 1.E-04 1.E-03 1.E-02 1.E-01 1.E+00
Frequency (Hz)
No
ise
(m
/s2 /H
z1/
2 )
Total
Detector
Wire damp
ADC
CPD
Meas
Recomb
PID
Electrostatic accelerometer MicroSTAR based on heritage of
CHAMP, GRACE and GOCE missions(developed by ONERA)
Bias Rejection System rotating stage with piezo-electric motor
(developed by ZARM)
Perfo ~ 1 pm/s2
For more details, see Benjamin Lenoir Poster
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General Relativity Test / Geodesy
Deep Space Gravity(OSS)
Gravitational Wave(LISA)
Equivalence Principle(Microscope)
GRACE / NGGMCHAMP GOCE
Orbit determinationMeasure of NG
Variation of Laser LinkDrag Compensation
Differential accelerationDrag Compensation
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OSS Spacecraft
RPW (x3)
MAG
Imaging instruments
Laser telescope
HGA
Towards Earth
Towards ram
Boresights direction for planetary observation GAP on
settable plate
ASRG
ASRG
4 tanks symmetric wrt GAP,
interconnected fluid
Imaging instruments
Fundamental Physics Inst.
DC Accelerometer : 3.5 kg / 3 WRadio-Science: 3.5 kg / 40 WUSO: 1.5 kg / 5.5 W1-way Laser Science: 14.5 kg / 20 W2-ways Laser Science:25 kg / 80 W
Planetary instruments
UV Spectrometer: 5.0 kg / 12 WHigh Resolution Narrow Camera: 9.8 kg / 14 WIR Spectrometer / Wide Angle Camera:
10.1 kg /7.5 WRadio Plasma Wave: 4.7 kg / 7.9 WThermal Map Imager: 7.0 kg / 20 WMagnetometer: 3.3 kg / 3 WDust Particle Detector: 3.5 kg / 9 W
S/C Data Sheet
Mass: 540 kg (48 kg payload)Available Power: 294 W BoL, 250 W EoLComm: 2.1 m antenna, Band KaAttitude Control: 3 axis (±0.03°)Propulsion: 4 tanks of hydrazine
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Self-gravity Management
• Accelerometer at S/C CoG• S/C mass far from accelerometer • Symmetry of tanks• Membranes for ergol location• Thermal Gauging & Book Keeping for ergol mass
Self-gravity < 14 pm/s2
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Conclusions
• OSS was not selected by ESA for Cosmic Vision M3• Fundamental Physics Objectives considered strong• Planetary Objectives considered weak (flyby instead orbiter)• RTG availability considered as a risk• Launcher cost by US considered as a strategic risk
• OSS allows to do pioneer work on• Merging of Fundamental and Planetary Physics as recommended by
FPRAT• Adaptative optics for 2-ways laser link• DC accelerometer with 1 pm/s2 accuracy• S/C design for severe self-gravity requirement
• Future works should concerns• Integration of the DC accelerometer in the S/C• Convincing planetary community of interest of accelerometer
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Acknowledgement to OSS scientific supporters
• European side: PI B. Christophe (ONERA)• CESR (France) : Nicolas André• DLR / Institute of Planetary Research (Germany): Ralf Jaumann, Jörn Helbert, Hauke Hussmann, Nicole Schmitz, Frank Sohl, Katrin Stephan• DLR / Institute of Space System (Germany): Hansjörg Dittus, Marco Sharringhausen, Tim van Zoest• GeoAzur / OCA (France) : Gilles Métris, Etienne Samain• IGEP, TU Braunschweig (Germany): Karl-Heinz Glassmeier, Daniel Heyner• Imperial College (United Kingdom) : Patrick Brown, Michelle Dougherty, Tim Sumner• Institute for Geophysics and Meteorology / Univ. Köln (Germany) : Martin Pätzold• Institute for Planetology / Westfälische Wilhelms Universität (Germany): Harry Hiesinger• Institut für Geowissenschaften / Max Planck Institute (Germany): Frank Postberg, Ralf Srama• Institut für Physik und Astronomie / Universität Postdam (Germany): Jürgen Schmidt• Instituto Superior Técnico (Portugal): Frederico Francisco, Paulo J.S. Gil, Jorge Páramos• JIVE (The Netherlands) : Sergei V. Progrebenko• LATMOS (France): Jean-Louis Bertaux, François Leblanc, Eric Quemerais• LESIA / Observatoire de Paris (France): Antonella Barucci, Baptiste Cecconi, Laurent Lamy• LKB / ENS (France) : Jean-Michel Courty, Brahim Lamine, Serge Reynaud• ONERA (France) : Bruno Christophe, Bernard Foulon, Benjamin Lenoir, Agnès Levy, Vincent Michau, Clélia Robert, Marc Séchaud, Pierre Touboul• Rutherford Appleton Laboratory (United Kingdom): Robert Bingham• Service d'Astrophysique/IRFU CEA Saclay (France) : Roland Lehoucq• SYRTE / Observatoire de Paris (France): Peter Wolf• Universidade do Porto (Portugal): Orfeu Bertolami• University of Oxford (UK): Leigh Fletcher• ZARM (Germany) : Claus Lämmerzahl, Hanns Selig
• US side: co-PI L. Spilker (JPL)• Cornell University: Dr. Don Banfield• JPL / NASA: Dr. John D. Anderson (retired), Dr. Sami W. Asmar, Dr. Glenn Orton, Dr. Kim R. Reh, Dr. Linda J. Spilker, Dr. Thomas R. Spilker• Lowell Observatory: Dr. Will Grundy• Planetary Science Institute: Dr. Candice Hansen• UCLA: Dr. Johnatan Aurnou, Dr. Ravit Helled, Dr. Kunio Sanayagi