May 1, 2007 A new distributed computing program analyzes data to characterize new planetary systems by computing the light reflected from nearby extrasolar planets and the wobble the planets cause in their stars and wobble combinations and compares them to known planet systems.
There are 209 known planets outside our solar system, but there are even more out there, and astronomers need help finding them.
Greg Laughlin, Ph.D., an astronomer at the University of California in Santa Cruz, says anyone can help. He explains, "You don't have to have any experience or knowledge of astronomy, just an interest is all that you really require to help us out."
University of California student Rion Parsons is happy to help look for other worlds. All he needs is a computer, the Internet, and some spare time. Parsons told DBIS, "The whole process of looking is really fun."
The out of this world project is called Systemic. It's a free web program that lets anyone hunt outer-space data to find our cosmic neighbors, which is not a one man job. Dr. Laughlin explains, "The kinds of computations that we need to do are computations that require a lot of computer power. They can be farmed out to a large number of individual computers."
The process works like this: stars, like our sun, reflect light off orbiting planets. Planets also tug on stars, causing them to wobble. Software measures the light and wobble combinations and compares them to known planet systems. Users submit the information to confirm a new planet.
Laughlin explained why it is fun for users. He says, "If you find a planet that hasn't been announced and then later find that the data supports your planet, then you have a real thrill of discovery."
More than 4,000 possible planets have been submitted, and four are awaiting confirmation. Parsons is still searching. He says, "I haven't found anything too amazing yet, but, you know, keep trying."
The American Astronomical Society contributed to the information contained in the TV portion of this report.
BACKGROUND: Astronomers at the University of California, Santa Cruz are seeking the public's help to find and understand planets outside our solar system. No advanced degree or fancy equipment is needed: just a computer, Internet access, and an interest in astronomy. The project is called Systemic, and it enlists volunteers to identify and explore other planetary systems in the Milky Way. This will help create a virtual database of extrasolar planetary systems. Several hundred people have already volunteered in the project's introductory phase.
HOW IT WORKS: Systemic is modeled on other successful public participation projects, such as SETI@home, where users download a screensaver that uses their personal computerýs processing power to analyze radio telescope data. But instead of just a screensaver, the astronomers wanted something that would more fully engage the user. The project involves a sophisticated simulation of the search for planets by creating a data set of 100,000 stars.
Participants can analyze this virtual galaxy themselves with freely available software. They can analyze the data for a target star. They can change planetary properties like mass, shape of the planet's orbit, and the time it takes for the planet to orbit its sun to find a configuration that best fits the data. Complicated large-scale simulation systems with multiple planets require a human eye and patience to arrive at an accurate description, which is a data-intensive, time-consuming process. By comparing the simulated observations with the real observations, the researchers hope to better understand how well, or how poorly, the search process collects a census of extrasolar planets.
WHY IT'S NEEDED: Albert Einstein's theory of general relativity says that gravity occurs because the mass of a celestial object, like the sun, warps the surrounding space-time. Planets orbiting the star follow that curvature. Astronomers find planets outside our own Solar system by measuring slight wobbles in a star's motion caused by the gravitational tug of an orbiting planet. Nearly 200 planets have been found orbiting other stars in our galaxy. However, this technique tends to locate planets that are both very large -- on a par with Jupiter -- and also close to their star. To make the process even slower, astronomers must share time on the few very large telescopes and are limited to observations lasting only a few days. This also limits what parts of the sky astronomers can observe, and thus the current data on planets outside our solar system is incomplete. Systemicýs simulated search uses the same kind of planetary wobble data that astronomers measure, as well as incorporating the observational biases that occur as they collect real data.