Washington, Apr 12 (IANS): A team of scientists has developed a new refined tool to search for exoplanets orbiting distant stars or other planetary detections.
One of the most successful techniques to find and confirm 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, there are limitations to the standard radial velocity method that may find something that looks like a planet but is not.
To address this issue, the team from Carnegie Mellon University, California Institute of Technology (Caltech) and Missouri State University 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," explained Jonathan Gagne from Carnegie.
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, he added.
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 att he NASA Infrared Telescope Facility atop Mauna Kea in Hawaii.
The 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,” added Caltech's Peter Gao in a paper published in The Astrophysical Journal.