The Stellar Planet Survey (STEPS) is an ongoing astrometric search for giant planets and brown dwarfs around a sample of ~30 M-dwarfs. We have discovered several low-mass companions by measuring the motion of our target stars relative to their reference frames. We describe the STEPS method for stellar centroiding that enables our ~1 milliarcsecond relative astrometry. We describe one of the astrometrically discovered companions, GJ 1210B, which was later confirmed with an imaging observation. GJ 1210 A and B have spectral types M4-5, based on their luminosities, inferred masses, and colors.
@article{arxiv.astro-ph/0501025,
title = {Discovering M-Dwarf Companions with STEPS},
author = {S. H. Pravdo and S. B. Shaklan and J. Lloyd and G. F. Benedict},
journal= {arXiv preprint arXiv:astro-ph/0501025},
year = {2007}
}