Deciphering General Characteristics
One aspect of this research that I find very interesting is that we may
be discovering enough planets so that we can begin to decipher some of the
general characteristics of the population.
This means that we can begin to address important questions, like how do
planets form, and how do their orbits evolve, and what are the implications for
finding rocky planets like our own in comfortable, stable orbits? But, the number of discovered systems is
still woefully inadequate for this kind of interpretation to be reliable, and
the selection effects are severe and dangerous. Thus, one of the main activities underway now is to carry out an
initial reconnaissance of large samples of stars, to identify additional
systems in large numbers, and to explore how the frequency and characteristics
of planets depend on parameters such as the mass of the primary star, or its
metallicity. Probably the best facility
in the world right now for this kind of work is located in Hawaii, halfway to
space (as the Hawaiians like to say) on the summit of Mauna Kea. Keck I, the first of the two 10-meter
telescopes (Figure 4) and the marvelous High Resolution Echelle Spectrograph
built by Steve Vogt, are getting heavy use for planet searches and follow-up
studies, supported primarily by NASA.
Several large Doppler surveys are underway with this facility and with
others around the world, and thousands of stars are being monitored. We can expect to see announcements of dozens
of new planets over the next several years.
Figure 4. Keck I
Contributed by: Dr. David Latham
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