Planets Around Sun-Like Stars
Picture Credit: E. Williams, G. Marcy, and L.-A. McConnaughey, (UC Berkeley), (SFSU)
Do many Sun-like
stars have
planets? Speculation on this point has been ongoing since
humanity's realization that other stars existed.
Only in the past year, however, have
answers and
discoveries been realized. The above plot summarizes the four
known cases of normal stars having planets. These cases are: our
Solar System,
51 Pegasi,
70 Virgini, and
47 Ursae Majoris. The later two cases
were discovered by astronomers led by
Geoff Marcy
and Paul Butler as part of a greater project inspecting 120 stars for
orbiting planets. Interestingly enough, the
planets around the later two stars have
temperatures
in the right range to allow
liquid water - and hence may have conditions
ripe for the development of
life.