What we do

We use the Fine Guidance Sensors aboard Hubble Space Telescope to measure star positions and study binary stars unresolvable using ground-based techniques. Stellar positions yield information on distance (parallax) and possible faint companions. We also work to tie the HIPPARCOS reference frame to an extragalactic (non-rotating) reference frame. Take a look at a few of our projects described in more detail.

A complete current projects list contains both GTO programs and those GO programs with which some of us are affliated.

What we've done

In the more than 20 years we have worked on this project, our paper production has evolved from "this is what we are going to do" to "this is what we did". We include recent papers and abstracts, and press releases as a guide to near-term future results. We've provided beautiful covers for the Astronomical Journal. We also developed software to aid us in our analyses.


While the misfigured primary mirror has caused us some problems (primarily a loss of binary star detection capability and measurement precision), our major irritation was that HST was not as stable a platform as we had hoped. The old solar arrays flexed and wiggled, driven by temperture changes caused by passage from sunlight to dark in each orbit. The new solar arrays , installed during the servicing mission in late 1993, are disturbing our platform far less.

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