The Kinematics of Main Sequence Stars from HIPPARCOS Data
Abstract
We analyze a kinematically unbiased sample of 5610 stars around the south celestial pole that (i) have MK spectral types in the Michigan catalogues with luminosity class V and (ii) had photometric parallaxes that placed them within 80 pc of the Sun. We bin the stars by B-V and determine for each bin the solar motion from proper motions alone. As expected, the U and W components of the derived solar motions do not vary significantly from bin to bin, while the V component varies systematically. As the classic Stroemberg relation predicts, V is a linear function of the variance S^2 within each bin around the solar motion. Extrapolating V(S^2) to S=0 we determine the solar motion with respect to the LSR, obtaining a significantly smaller value of V than is usually employed. Parenago's discontinuity in the dependence of S^2 on spectral type emerges with exceptional clarity.
- Publication:
-
Hipparcos - Venice 1997
- Pub Date:
- August 1997
- Bibcode:
- 1997ESASP.402..473B