Subject: [SLR-Mail] No. 843: ILRS Mission Support of GRACE
From: Carey Noll <Carey Noll <noll@cddisa.gsfc.nasa.gov>>

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SLR Electronic Mail          2001-11-28 09:29:00 UTC           Message No. 843 
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Author: Carey Noll
Subject: ILRS Mission Support of GRACE

Dear Colleagues:

The ILRS Governing Board has approved tracking of the GRACE mission,
presently scheduled for launch in early 2002.  SLR will complement GPS
tracking in support of POD for gravity field recovery.  Strategies to
track the two closely separated satellites are under discussion within
the SLR community.  The SLR Mission Support Request submitted by the
GRACE mission team is included below.  More information about the mission
can be found at the web sites:
http://www.csr.utexas.edu/grace/
http://op.gfz-potsdam.de/grace/index_GRACE.html

Regards,

Carey Noll.
Secretary, ILRS Central Bureau

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Name: GRACE (Gravity Recovery And Climate Experiment)

Host: NASA

Primary Tech Contact: Byron Tapley, UTCSR

Primary Science Contact: Byron Tapley, UTCSR

Alternate Tech Contact: Ab Davis, NASA/JPL

Alternate Science Contact: Christoph Reigber, GFZ

Tech Mailing Address: University of Texas at Austin, Center for Space
Research, 3925 W. Braker Lane, Ste. 200, Austin, TX, 78759, USA

Science Mailing Address: University of Texas at Austin, Center for
Space Research, 3925 W. Braker Lane, Ste. 200, Austin, TX, 78759, USA

Tech Fax: +1(512) 232-2443

Science Fax: +1(512) 232-2443

tech email: tapley@csr.utexas.edu

science email: tapley@csr.utexas.edu

Tech Web_Address: http://www.csr.utexas.edu/grace/

Science Web_Address: http://www.csr.utexas.edu/grace/

mission objectives: GRACE is a joint US/German satellite mission 
which will provide global high resolution estimates of the Earth&#180;s 
gravity field and its variability in time. For a detailed outline see

http://www.csr.utexas.edu/grace/                      or

http://op.gfz-potsdam.de/grace/index_GRACE.html

mission role: Complementary tracking system to onboard GPS for POD 
and for GPS data validation

launch date: Early 2002 

mission duration: 5 years

altitude: 500 - 300 km

inclination: 89.0 degrees

eccentricity: < 0.005

tracking sched: Start of SLR tracking immediately after separation of
S/Cs

spatial cov: Global

temporal cov: All times

data accuracy: Millimeter to centimeter ranging accuracy

coordinator: Rolf Koenig, GFZ

priority: Complementary to GPS

data source: GFZ

POD source: GPS

Analysis Center: UTCSR

npt time span: 5 s

tracking requests: All

delivery time: 0.5 h after data take at ILRS data centers

array info: 4 cube corner prism array, nadir facing. See
http://op.gfz-potsdam.de/grace/index_GRACE.html

tech contact for array info: Ludwig Grunwaldt

array contact number: grun@gfz-potsdam.de ; +49-331-288-1733

Comments: Drawing of satellite and array for mission planning 
purposes is available on 

http://op.gfz-potsdam.de/grace/index_GRACE.html

A proposal for scheduling twin tracking of both S/C
is in process.

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Ms. Carey Noll  Manager, Crustal Dynamics Data Information System (CDDIS)
Code 920.1                             E-mail:  noll@cddisa.gsfc.nasa.gov
NASA GSFC                                           Voice: (301) 614-6542
Greenbelt, MD 20771                                   Fax: (301) 614-5970
USA                  WWW:  http://cddisa.gsfc.nasa.gov/cddis_welcome.html
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From: Carey Noll <noll@cddisa.gsfc.nasa.gov> 

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