Has there been any previous attempts or proposals to measure more
accurately the Parallax of stars by using a telescope on a space probe
which will travel into deep space thereby increasing the baseline by a
factor of 10 or more and
thus resulting in a much more accurate parallax measurement?

Hello mongolia-ga,

The Space Interferometry Mission (SIM), scheduled for launch in 2009,
will determine the positions and distances of stars several hundred
times more accurately than any previous program. This accuracy will
allow SIM to determine the distances to stars throughout the galaxy
and to probe nearby stars for Earth-sized planets.

“SIM is being developed by the Jet Propulsion Laboratory under
contract with NASA and in close collaboration with two industry
partners, Lockheed Martin Missiles and Space in Sunnyvale, California,
and TRW Inc., Space and Electronics Group in Redondo Beach,
California”
NASA: (SIM) space interferometry mission 
http://planetquest.jpl.nasa.gov/SIM/sim_what_is.html

Sim will be able to measure distances of stars with an improvement of
several hundred times over what is possible today.

“The Space Interferometry Mission will measure the position of stars
with an accuracy of 4 microarcseconds and will see parallaxes at a 10
percent accuracy level out to a distance of 482,000 million million
miles (or in astronomical units 25,000 parsec). In other words, SIM
would be able to see the grass in your yard grow every second, from as
far away as 10 kilometers, or more than 6 miles. With this accuracy
SIM will be able to measure the distance to any object in our Milky
Way Galaxy, as long as it's bright enough. This is an improvement of
several hundred times over what is possible today"

NASA: (SIM) space interferometry mission 
http://planetquest.jpl.nasa.gov/SIM/sim_measuring.html

The Mission

“The SIM spacecraft would be carried into orbit via the Space Shuttle,
though other launch options are also being explored. Once ejected from
the shuttle payload bay, initial deployments and checkout will take
place. Next, SIM will gradually be boosted into an orbit about the
Sun, via use of an integral propulsion module (IPM). In its final
orbit the spacecraft will slowly drift away from the Earth at a rate
of approximately 0.1 AU per year, reaching a maximum communication
distance of about 95 million kilometers after 5.5 years.”
NASA: (SIM) space interferometry mission 
http://planetquest.jpl.nasa.gov/SIM/sim_mission.html


Additional information that may interest you:

European astronomers designed the Hipparcos satellite specifically to
measure the parallax of nearby stars.  (..) Over the course of 3 years
in orbit, Hipparcos made millions of measurements of thousands of
stars. It measured the motion of each star about 100 to 150 times:
(..) The measurements made by Hipparcos were about ten times more
precise than those made by most ground-based telescopes. In addition,
Hipparcos was able to measure over 100,000 stars, which was way, way
more than all the astronomers in the history of the science had been
able to do from the ground. It was a real breakthrough. “
Michael Richmond at the Rochester Institute of Technology
http://spiff.rit.edu/classes/phys240/lectures/parallax/parallax.html


From a lecture by David Boal – Simon Fraser University
http://www.sfu.ca/~boal/390lecs/390lec1-2.pdf
“There is a lower limit to the minimum parallax that can be detected,
and this places an upper limit on how far away a star’s position can
be deduced using parallax. Space-based telescopes can detect p ~ 10-3
arc seconds, ten times better than typical resolution on Earth. This
distance limit corresponds to
d = 1 / 10-3 = 103 pc ~ 3000 ly (small compared to 30,000 ly to the
galactic centre)”


Search Criteria:

parallax measurement from a space probe
space based telescopes parallax measurement
parallax measurement from space


I hope that this information meets your needs. If anything I have
written is not clear, or if this is not the information you require,
please make a request for clarification and I will do my best to meet
your needs.


Best Regards,
Bobbie7-ga

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Request for Answer Clarification by mongolia-ga on 23 Feb 2003 07:23 PST

Dear Bobbie7
 
Indirectly you have answered by question. The URL's you have sent me
do indeed explain how the SIM spaceprobe will measure parallax's more
accurately than any measurements made up to now.
 
The real intent of my question was if any thought had been given to
the idea of increasing the accuracy simply by sending the spaceprobe
very far from earth (Lets say beyond the orbits of Jupiter or Saturn)
thereby increasing the base line by a large factor.

It would appear though that SIM will produce more accurate PARALLAX 
measurements using INTERFEROMETRY techniques. This would therefore
eliminate the need for what I have suggested.

 Regards
 Mongolia

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Clarification of Answer by bobbie7-ga on 23 Feb 2003 08:44 PST

Dear Mongolia,

In my research, the most accurate Parallax Measurements appears to be
via the SIM spaceprobe. Given the intent of your question, would you
prefer that I make a request to the editors for the removal of my
answer or does my answer satisfy you even so?

Thank you for your understanding.

Regards,
Bobbie7

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Request for Answer Clarification by mongolia-ga on 26 Feb 2003 05:16 PST

Dear BOBBIE7

I would still like to  search if there is any refeence to the  idea I
proposed.

 If you cannot find any reference ,I will of course accept your answer
as perfectly acceptable.

 Cheers 

  Mongolia

---

Clarification of Answer by bobbie7-ga on 26 Feb 2003 05:56 PST

Thank you for you patience Mongolia.
I will continue my search.
Bobbie7

---

Clarification of Answer by bobbie7-ga on 26 Feb 2003 08:47 PST

Hello again Mongolia,

I located the following reference of Interstellar Rocketry and
parallax measurements:

“Project Longshot was developed by the U.S. Navy and NASA in 1988 as a
design for an unmanned probe to Alpha Centauri.

(..)

Longshot would be assembled at International Space Station Alpha, and
would have a flight time of approximately 100 years.

(..)

The primary missions of Longshot are investigation of the interstellar
medium, investigation of the Alpha Centauri system, and Earth-Centauri
astrometry. Making parallax measurements with a baseline of 4.34
lightyears will increase accuracy of distance measurements to stars by
a factor of sixty thousand. Accurate distance measurements could be
made for stars up to 1.2 million parsecs away.”

Scientium: Interstellar Rocketry
http://216.239.57.100/search?q=cache:KQ6650EwNWoC:scientium.com/Commentary/Bowden_Essays/startrip/starship/rockets.htm+telescope+for+parallax+measurements+on+space+probe&hl=es&ie=UTF-8

Search Criteria:
telescope parallax measurements on space probe


I hope this is what your're seeking. If you need further information
please let me know.

Best Regards,
Bobbie7-ga