- Scientific Mission:
- Infrared Astrometry (precise 3D mapping of positions and transverse velocities of stars with an accuracy of 1 milli-arcsecond in an infrared region)
- Engineering Mission:
- Demonstration of new satellite technologies including a precision mission telescope, precise attitude / thermal control (1 arecsec / 0.1 deg K), and satellite simulation
|Mass||35 kg (TBC) without separation mechanism|
|Size||50 cm cubic (TBC)|
|Attitude Control||Three axis stabilization|
|Communication||S-band / 100kbps|
|Mission Life||Two years|
|Orbit||Sun-Synchronous Orbit, LTAN(Local Time of Acsending Node) is TBC.|
|Mission life||2 years|
|Diameter of primary mirror||5cm|
|Relative angle of two FOVs|| 99.5 |
|Focal length||1.67 m|
|Field of view|| 0.5|
|Detector|| Back illuminated full depletion CCD, 1K |
|Pixel size|| 15|
|Spin period||100 min(TBC in detail according to the orbit hight),(0.001047rad / sec in angular velocity)|
|Exposure time||8.2sec(detector transit time of each stars)|
|precession time||2 month(TBC) around the Sun|
|Spin axis direction|| constant angle 45|
|Accuracy||3mas @ z = 7.5|
Major characteristics are shown in the table.
- Pre-phase A study started in 2003
- Conceptual design started in 2005
- Tests for Engineering Qualification Model was completed within 2009
- Flight Model to be completed in early 2011, and test complete at the end of FY 2011
- Launch scheduled for 2014
the operating principles of nano-Jasmine
- at the end of 2014 ∼ from Alcantera launch site in Brazil by a Ukrainian Cyclone-4 vehicle
- Initial hardware checkout
- about 1 month.
- Determine the satellite orbit
- On board GPS data reception. Kinematic point positioning in postprocessing on ground.
- Nominal observation
- 2 years (not guranteed).
- University of Tokyo 3m antenna and hopefully NAOJ Mizusawa 10m, 2 or 3 path in every 12hours.
Diameter of the primary mirror is 5cm. There are several folding mirrors in light path. Beam combiner is located in front of the primary mirror. Its angular stability (1 mas / 2 hours) is confirmed on FEM computation, and was checked in STM tests in July 2008.
Nano-JASMINE telescope observed anti Earth direction. Scanning angular velocity is determined as synchronous to the satellite orbital period.
information on the scanning law
Nano-JASMINE observes 99.5
design of the focal plane
There is only one 1K
Attitude and orbit are detected with star tracker and GPS on board.
LSF centroiding accuracy
Following to GAIA, PSF fitting is used for Centroid algorithms, and charge distortion model is applied for the change of CTI by radiation damage. We already confirmed the performance of center of mass method, and achieved 1/150 pixel accuracy. Dr. F. van Leeuwen suggest us (in JASMINE case) that PSF fitting should be also considered.
Data accuracies in indivisual steps are listed in the below table.
|stage|| 0.81|| 0.6|
|successive 2 spin observations||7.3mas||3.0mas|
|(including parallax factor)||3.8 mas||1.55mas|
The core data reduction for the Nano-JASMINE mission is planned to be done with Gaia's Astrometric Global Iterative Solution(AGIS). The collaboration started at 2007 prompted by Michael Perryman's idea and Uwe Lammers' proposal. In addition to similar design and operating principles of the two missions, this is possible thanks to the encapsulation of all Gaia-specific aspects of AGIS in a Parameter Database. Nano-JASMINE will be the test bench for Gaia AGIS software. The Nano-JASMINE catalogue will be more reliable because we can use well tested data reduction software.
Science working group starts at Feb. 2010. The leader is Asoc. Prof. Ryoichi Nishi at Niigata University. We now start to study what science will be available with astrometric data of Nano-JASMINE accuracy.
- Mission Payload:
- Jasmine Project Office, National Astronomical Observatory of Japan, Department of Physics, Kyoto University, etc.
- Spacecraft Bus:
- Intelligent Space Systems Laboratory, University of Tokyo