Log file for SPACIT Version 7.1.1.
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Comments From File: math9749.bsp
Objects In This Ephemeris
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Name Id-code
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Asteroid Mathilde...2000253
Approximate Time Coverage
From: February 9, 1996
To : January 24, 2002
Status
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This is the latest official Mathilde ephemeris for use by the NEAR
project. It represents the latest knowledge of the position of the
asteroid Mathilde as of June 25, 1997.
This ephemeris (math9749.bsp) updates and replaces the ephemeris of
June 11, 1997 --- math9740.bsp.
IF YOU HAVE THE FILE math9740.bsp, YOU SHOULD REMOVE IT FROM YOUR
SYSTEM.
No updates to this ephemeris are planned.
Production/History of this Ephemeris
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This ephemeris was produced by Bill Taber of the Navigation Ancillary
Information Facility (NAIF) at the Jet Propulsion Laboratory on June
25, 1997 for use by the NEAR project. It was transformed to SPK format
from a numerical integration performed by Don Yeomans of the Solar
Systems Dynamics group of the Astrodynamics and Navigation section
(section 312) of the Jet Propulsion Laboratory. Yeomans' internal
solution number for this ephemeris is solution 49.
The ephemeris is based on observations over the interval 1885 Dec.
to June 24, 1997. The observations include several recent observations
reduced relative to the Hipparchos Star Catalog.
The ephemeris was integrated using the JPL developmental ephemeris
DE-403 to provide a gravitational force model.
Usage
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To determine the state of Mathilde with respect to any object other
than the sun, you need at a minimum a planetary ephemeris. Since the
planetary ephemeris used for the dynamical force model in the
integration of the Mathilde ephemeris was DE-403, it is highly
recommended that you use DE403 when computing states of Mathilde with
respect to anything other than the sun.
DE403 is available via anonymous ftp on NAIF's ftp server: naif-sun
(ip address 128.149.126.11) in the directory
pub/naif/generic_kernels/spk. Both binary and transfer format
ephemerides are available. They are in the files.
de403s.bsp ( binary format )
de403s.xsp ( transfer format )
de403s.cmt ( comments about de403s )
To determine the state of Mathilde with respect to the NEAR spacecraft
you will need a trajectory file for the NEAR spacecraft. At present
NAIF does not possess such a trajectory file. We recommend that you
contact the NEAR project for assistance in obtaining a NEAR spacecraft
ephemeris.
The current estimate for the radius of Mathilde is:30.5 km.
The current estimate for the GM of Mathilde is : 0.0198 km**3/sec**2
Accuracy
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The plane of the sky residuals in the position of Mathilde as viewed
from earth relative to the Hipparchos catalog are less than 0.5
arcseconds.
The current estimated 1-sigma uncertainty in the position of Mathilde
at the time of NEAR encounter is approximately 186 km in the direction
of Mathilde's velocity, 32 km in the direction orthogonal to the
orbital plane of Mathilde and 30 km in the direction radial from the
sun.
In B-plane coordinates the 1-sigma uncertainty in the position of Mathilde
are
Radial component --- T : 152 km;
Out of plane --- R : 34 km;
Time of Flight --- S : 111 km.
(See the reference sited below for a more detailed analysis of
the accuracy of this ephemeris).
References
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JPL IOM 312.1-96-031 dated June 4, 1997.
Inquiries
If you have any questions regarding this ephemeris contact
Bill Taber
btaber@spice.jpl.nasa.gov
Phone (818) 354-4279
FAX (818) 393-6388
JPL
MS 301/125L
4800 Oak Grove Drive
Pasadena, CA 91109
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Summary for SPK file: math9749.bsp
Leapseconds File : /usgs/cpkgs/isis3/data/base/kernels/lsk/naif0010.tls
Summary Type : Entire File
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Segment ID : Asteroid Mathilde
Target Body : Body 2000253, MATHILDE
Center Body : Body 10, SUN
Reference frame: Frame 1, J2000
SPK Data Type : Type 8
Description : Discrete States, Evenly Spaced, Lagrange Interpolation
UTC Start Time : 1996 FEB 08 23:58:57.815
UTC Stop Time : 2002 JAN 23 23:58:55.815
ET Start Time : 1996 FEB 09 00:00:00.000
ET Stop time : 2002 JAN 24 00:00:00.000
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