Newly Discovered Planet Helps Explain Our Solar System

Author:  Doshi Ojus

Date:  August 2007

Last week, scientists at Penn State University announced the discovery of a new planet orbiting a star ten times larger than our sun. The find will help astronomers determine the evolution of a solar system, resembling our own, as the central star ages and expands, and will be published in the November issue of the journal Astrophysics.

"This planet. is in one of the most distant of the ten published solar systems discovered around red-giant stars," said Lawrence Ramsey, a member of the discovery team and the head of the Department of Astronomy and Astrophysics at Penn State. The team, led by Dr. Alex Wolszczan, used the Texas-based Hobby-Eberly telescope to find the planet and is part of a collaboration of researchers from Nicholas Copernicus University in Poland, the California Institute of Technology and the McDonald Observatory.

"We want to know how often do planets form around stars that were more massive than our Sun," Wolszczan said. "Obviously, the more solar systems around red giants we discover and study, the better chance we have to really understand the big picture of planet formation."

The published results come after three years of research, in which the scientists looked at data for thousands of red-giant stars with the potential for possessing Jupiter-sized planets. Fluctuating light spectra from a certain star indicated a change in the star's velocity caused by the gravitational pull of a planet. After closely observing a star in the constellation Perseus, the astronomers saw patterns of change that confirmed the presence of a planet.

From this discovery and any similar finds in the future, the researchers hope to deduce which other planets may become habitable once our own Sun expands too much for life to continue on Earth.

"When our Sun becomes a red giant, Earth and the other inner planets very likely will dive into it and disappear," Wolszczan explained.

In addition, the research group aims to build on existing knowledge about the evolution of stars and planets in a solar system.

"We really are at the very beginning of this effort, and it is going to take time to get a consistent picture of planetary formation and evolution," Wolszczan said. "The more we learn, the greater the chance will be that sooner or later we will discover how ordinary or extraordinary is our home -- the Earth's solar system."

Written by Ojus Doshi