A long-lost "sister" star to our own sun has been identified in the constellation of Hercules.
This star is the first ever found that was created in the same "birth cluster" as our own stellar companion. Astronomers believe that this star, like its sibling, may host worlds capable of supporting life.
The star, designated HD 162826, was one of 23 candidates studied by astronomers looking for a sibling to the sun. Orbital elements of the star were traced back, and found to be aligned with the birthplace of our own sun. By breaking light from HD 162826 into its component colors, astronomers were able to determine the trace chemical makeup of the star, confirming its heritage.
"We find that chemical tagging does not necessarily benefit from studying as many elements as possible, but instead from identifying and carefully measuring the abundances of [certain] elements... Future searches [and] surveys can be optimized by acknowledging this fact," researchers wrote in the article announcing their findings.
The newly-discovered star is roughly 110 light years from the Earth, and approximately 15 percent more massive than the sun.
This star is too dim to be seen with the naked eye. Long before the realization of the pedigree of HD 162826, astronomers had studied the star, looking for planets. The presence of large worlds around the stellar body is unlikely, according to astronomers. However, smaller planetary bodies could still orbit around the alien sun, and some of these may be in the "habitable zone." This is a range of distances from a star at which water is likely to exist in liquid state, possibly encouraging the development of life. Worlds the size of Earth are difficult to find, and only recently have such discoveries become more common.
This new method of tracing stellar evolution may be employed by astronomers studying other stars. This could allow scientists to determine which stars were born together, along with possibly identifying other sister stars to our own sun. This information could open up new information about stellar evolution and the role our own sun plays in the galaxy.
"We want to know where we were born. If we can figure out in what part of the galaxy the sun formed, we can constrain conditions on the early solar system. That could help us understand why we are here," Ivan Ramirez of The University of Texas, lead researcher on the study, said.
Discovery of the new star, and the study which reveled its unique relationship to our sun, will appear in the Astrophysical Journal.
