Early planet searching... Jul 6, 2005 18:21:28 GMT -6
Post by Chicago Astronomer Joe on Jul 6, 2005 18:21:28 GMT -6
The Barnard's Star Blunder
These days, it is generally accepted within the scientific community that there are planets orbiting nearby stars. In the past decade, more than 130 such extrasolar planets have been discovered. But the first such "discovery," of a planet allegedly orbiting Barnard's star, turned out to be a false alarm. In a talk at a recent symposium on extrasolar planets, astronomer Alan Boss, of the Carnegie Institution of Washington, told the tale of this scientific snafu.
The extrasolar planets field started in many ways with Peter Van de Kamp. Van de Kamp had been a professor at the University of Virginia for several years. In 1937 he went to Swarthmore College and became director of the Sproul Observatory there. The next year he began a long-term search for very low-mass companions to stars. One of the first stars he put on the search program was a star called Barnard's star. Barnard's star is the second closest star system to our own. The only one closer to us is the Alpha Centauri triple system. Unfortunately, it's an M dwarf, so it can't be seen by the visible eye, but it can be easily seen with a small telescope.
Van de Kamp started taking data on Barnard's star in 1938, and continued taking data for roughly 25 years. In 1963, he finally felt confident enough to present his first results. These were pretty excruciatingly difficult measurements. He and his colleagues were looking for variations of plus or minus 1 micron in the position of the star on a photographic plate. They were trying to measure the photo center of these little blurry dots on the photographic emulsions to 1 part in 100. They would have 10 people measure the same plates independently, and then try to average over whatever individual systematic errors they would introduce, to find the true photo center of the positions.
The entire story here: www.astrobio.net/news/article1635.html
Visionaries often are thought of as kooks early on by the mainstream. I dismiss them.