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: http://www.stsci.edu/stsci/meetings/planets/abs/prog20.html
Дата изменения: Tue Oct 22 19:36:13 1996 Дата индексирования: Sun Dec 23 00:54:15 2007 Кодировка: |
Our curiosity is naturally drawn to the solar-type stars (G dwarfs, roughly) since we live around one ourselves, and they are also - perhaps not coincidentally - a preferred sample when looking for planets beyond the solar system. This is because G dwarfs, especially old ones like the Sun, are:
A census of the nearby solar-type stars is in progress. It will soon use colors and parallaxes from Hipparcos to define a volume-limited sample of ~5,000 G dwarfs within 50 pc (i.e., down to a V magnitude of about 9). A preliminary estimate of which stars these are has been made, based on existing information. Additional observations are being made to determine which stars are in binary systems, and it is also possible to estimate ages. Stars that have stellar companions within ~10 AU are not promising targets for planet searches, nor are the very young stars. Both qualities - duplicity and age - weed out about 1/2 of the starting sample, meaning that ~1/4 of the stars are suitable targets. That is about 1,000 stars, roughly, or 1 µSagan.
In this talk I will discuss some of what is known about stars like the Sun, how that can be applied to the search for extra-solar planets, and some of the other motivations for pursuing these studies.
Last update: 10/22/96 11:00:29