Geoff Marcy and Paul Buttler have discovered their fourth extra-solar planet. For updates on their progress, visit their web site The Search for Extra-Solar Planets. The 'F7' star Tau Bootis is a 4.5 magnitude star located about 60 light years away and is slightly hotter than the Sun. Tau Bootis The purported planet has a mass of perhaps 3.6 Jupiters and orbits once every 3.3 DAYS! It is 6.9 million miles from Tau Bootis. The star has a companion called GL 527B in an orbit with a radius of 540 AU. CAMERON A., HORNE K., PENNY A. & JAMES D., in 1999 announced "Probable detection of starlight reflected from the giant exoplanet orbiting Tau Bootis. Which was published in the Journal Nature, volumn 402, page 751.
The velocity curve, confirmed by the Harvard AFOE group is as follows:
Copyright 1997 Dr. Sten Odenwald
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