LAGEOS Flash Observation Program
Douglas Currie (currie@nscpmail.physics.umd.edu)
Thu, 24 Apr 1997 13:39:49 -0400
The following is in conformity with the SeeSat request for new
subscribers to introduce themselves. It also serves to invite
interested members of SeeSat-L Network to provide a unique contribution
to our project at the University of Maryland for the confirmation of the
General Theory of Relativity and to support an International Geophysical
and Geodetic Observational Program.
The LAGEOS geodetic satellites (08820 and 22195) produce a
series of
glints or flashes. While these are too faint for naked-eye
observations, they may easily be seen with a small telescope. Timing
information on these flashes permit the estimation of the spin axis of
the satellite. The orientation of the spin axis determines the photon
thrust (a.k.a. photon recoil forces, photon rocket forces, and
Earth-Yarkowsky and Solar Yarkowsky effects) which is the largest un-
modeled force affecting the orbit of these satellites.
We have been observing these glints over the past eight years at
the
Geophysical, Geodetic, and Astronomical Optical Site of the Goddard
Space Flight Center. Petras Avizonis has just completed a Ph.D. thesis
which, among other objectives, demonstrated that these measurements may
be used obtain a very precise determination of the spin axis
orientation, and to track the dynamical evolution of the rotational
vector of LAGEOS I.
The project has thus reached the stage that a continuous
monitoring of
the rotational vector can be used for the analysis of the orbits of the
LAGEOS satellites, and thus significantly contribute the to the
Geophysical, Geodetic and General Relativistic Science of the Satellite
Laser Ranging Program of NASA and the National Space Agencies of other
countries.
In conclusion, I would like to invite you to see a more detailed
description of our program , which is described on our web page for the
LAGEOS Spin Axis Monitoring Network:
http://www.physics.umd.edu/rgroups/astro-metro/lageos/lagchoice.html
These Web Pages are still under construction. The pages with
the
description of the LAGEOS Monitoring Program, and the methods of
observing are compete. The registration and data entry pages should be
available in a few days. The orbit and burst prediction pages, required
for those without LAGEOS elements, will be a little longer.
Please direct any questions, comments, suggestions or
complaints, on
either our Program or the Web pages to me at --
currie@hubble.physics.umd.edu -- . This is an exciting program, and
your contribution will help to make you and the amateur community
significant participants of this endeavor. I look forward to this
collaboration.
Doug Currie
Professor of Physics
University of Maryland
The following is in conformity with the SeeSat request for new
subscribers to introduce themselves. It also serves to invite
interested members of SeeSat-L Network to provide a unique contribution
to our project at the University of Maryland for the confirmation of the
General Theory of Relativity and to support an International Geophysical
and Geodetic Observational Program.
The LAGEOS geodetic satellites (08820 and 22195) produce a
series of
glints or flashes. While these are too faint for naked-eye
observations, they may easily be seen with a small telescope. Timing
information on these flashes permit the estimation of the spin axis of
the satellite. The orientation of the spin axis determines the photon
thrust (a.k.a. photon recoil forces, photon rocket forces, and
Earth-Yarkowsky and Solar Yarkowsky effects) which is the largest un-
modeled force affecting the orbit of these satellites.
We have been observing these glints over the past eight years at
the
Geophysical, Geodetic, and Astronomical Optical Site of the Goddard
Space Flight Center. Petras Avizonis has just completed a Ph.D. thesis
which, among other objectives, demonstrated that these measurements may
be used obtain a very precise determination of the spin axis
orientation, and to track the dynamical evolution of the rotational
vector of LAGEOS I.
The project has thus reached the stage that a continuous
monitoring of
the rotational vector can be used for the analysis of the orbits of the
LAGEOS satellites, and thus significantly contribute the to the
Geophysical, Geodetic and General Relativistic Science of the Satellite
Laser Ranging Program of NASA and the National Space Agencies of other
countries.
In conclusion, I would like to invite you to see a more detailed
description of our program , which is described on our web page for the
LAGEOS Spin Axis Monitoring Network:
http://www.physics.umd.edu/rgroups/astro-metro/lageos/lagchoice.html
These Web Pages are still under construction. The pages with
the
description of the LAGEOS Monitoring Program, and the methods of
observing are compete. The registration and data entry pages should be
available in a few days. The orbit and burst prediction pages, required
for those without LAGEOS elements, will be a little longer.
Please direct any questions, comments, suggestions or
complaints, on
either our Program or the Web pages to me at --
currie@hubble.physics.umd.edu -- . This is an exciting program, and
your contribution will help to make you and the amateur community
significant participants of this endeavor. I look forward to this
collaboration.
Doug Currie
Professor of Physics
University of Maryland
--
======================================================
Douglas G. Currie currie@hubble.physics.umd.edu
Astro-Metrology Group Office Voice (301) 405 6046
Department of Physics Office FAX (301) 314 9525
University of Maryland Home Voice (301) 384 6602
College Park, MD 20742 Home FAX (301) 384 5329
http://www.physics.umd.edu/rgroups/astro-metro/
======================================================