New model developed to identify habitable zones around star
Washington, January 31 : Using the latest data, a team of Penn State researchers including one of Indian origin has developed an updated model for determining whether discovered planets fall within a habitable zone.
The work builds on a prior model by James Kasting, Evan Pugh Professor of Geosciences at Penn State, to offer a more precise calculation of where habitable zones around a star can be found.
Comparing the new estimates with the previous model, the Penn State Department of Geosciences team found that habitable zones are actually farther away from the stars than previously thought.
"This has implications for finding other planets with life on them," said post-doctoral researcher Ravi kumar Kopparapu, a lead investigator on the study, which will be published described in Astrophysical Journal.
For the paper, Kopparapu and graduate student Ramses Ramirez used updated absorption databases of greenhouse gases (HITRAN and HITEMP). The databases have more accurate information on water and carbon dioxide than previously was available and allowed the research team to build new estimates from the groundbreaking model Kasting created 20 years ago for other stars.
Using that data and super computers at Penn State and the University of Washington, the team was able to calculate habitable zones around other stars. In the previous model, water and carbon dioxide were not being absorbed as strongly, so the planets had to be closer to the star to be in the habitable zone.
The new model has already found that some extrasolar planets previously believed to be in habitable zones may, in fact, not be.
The new model could also help scientists with research that is already under way. For example, the model could be used to see if planets the NASA Kepler mission discovers are within a habitable zone. The Kepler mission has found more than 2,000 potential systems that could be investigated.
The study will be published described in Astrophysical Journal.