Planet-hunting just got refined with new tool

Planet-hunting just got refined with new tool

Submitted by alvin on Tue, 2016-04-12 18:00 Washington D.C: A team of planet hunters has come up with a new tool that refines exoplanet search.New work led by Carnegie's Jonathan Gagne, Caltech's Peter Gao, and Peter Plavchan from Missouri State University reports on a technological upgrade for one method of finding planets or confirming other planetary detections.One of the most-popular and successful techniques for finding and confirming planets is called the radial velocity method. A planet is obviously influenced by the gravity of the star it orbits; that's what keeps it in orbit. This technique takes advantage of the fact that the planet's gravity also affects the star in return.As a result, astronomers are able to detect the tiny wobbles the planet induces as its gravity tugs on the star. Using this method, astronomers have detected hundreds of exoplanets.For certain kinds of low-mass stars, however, there are limitations to the standard radial velocity method, which can cause false positives -- in other words, find something that looks like a planet, but isn't.To address this issue, researchers decided to use the radial velocity technique, but they examined a different, longer wavelength of light."Switching from the visible spectrum to the near-infrared, the wobble effect caused by an orbiting planet will remain the same regardless of wavelength," Gagne explained. "But looking in the near-infrared will allow us to reject false positives caused by sunspots and other phenomena that will not look the same in near-infrared as they do in visible light,"The research team was able to develop a better calibration tool to improve the overall technology for near-infrared radial velocity work, which should make it a better option going forward.They examined 32 low-mass stars using this technological upgrade atthe NASA Infrared Telescope Facility atop Mauna Kea, Hawaii. Their findings confirmed several known planets and binary systems, and also identified a few new planetary candidates."Our results indicate that this planet-hunting tool is precise and should be a part of the mix of approaches used by astronomers going forward," Gao said. "It's amazing to think that two decades ago we'd only just confirmed exoplanets actually existed and now we're able to refine and improve those methods for further discoveries."The result is published by The Astrophysical Journal. (ANI)