A Few Representative Projects

An Extrasolar Planet Search

We search for PLANETS near Proxima Centauri and Barnard's Star by detecting wiggles in their motion. Why would Proxima Cen wiggle? It and any associated planet would orbit a common center of mass. No, we have not found any planets, yet. Here is some information about Proxima Centauri and a status report on our search.
Often in astronomy one looks for one thing and finds another. The FGS are also very good photometers. Proxima Centauri turned out to be a periodic variable star. The announcement paper was based on less than half the data sets we have now. The period may have changed to 82 days from the originally announced 41 days. Finally, here is an example of the periodograms which we use in our search. The only frequency for which there is any power in both x and y is near 0.013 /day. We remain skeptical that it is an astronomical effect.

Hatzes, Kuerster, and Cochran are obtaining high precision (+/- 100 m/s) radial velocity measures of Proxima Cen from ESO. We should know if the planet exists or not by comparing periodicities seen in the astrometry with any found in the radial velocity results. So far, the eight epochs obtained over 2 years are not inconsistent with a variation with a period near 90 days. More data are required to rule out noise as the producer of this variation.

Here is some information about Barnard's Star . We are in the middle of our series of observations of this object. They will continue through 1995-6 (Cycle 5). Thus far, neither astrometric nor radial velocity measurements have yielded a planet.

Cleaning Up the Hyades Color-Magnitude Diagram

Here is a color picture of a typical star cluster (M35). The color-magnitude (or Hertzsprung-Russell) diagram shows the main-sequence to have width. Some of this width is due to unresolved binary stars. We are inspecting many members of the Hyades star cluster in an effort to tighten up the HR diagram. The Hyades are a cornerstone of the cosmic distance scale.

POS Mode Calibration of FGS 3

The Parallax of delta Cephei

Jupiter Relativity Experiment

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