A team of scientists led by University of Texas, Austin, astronomer Ivan Ramirez have identified a star that they believe is one of many siblings our sun has floating around the Universe. Formed 4.5 billion years ago from the same large interstellar cloud that gave birth to our sun, it is 15% larger and lies 110 light-years away in the constellation Hercules. Though not visible with the unaided eye, HD 162826 that lies close to bright star Vega, can be easily viewed with low-power binoculars.
The team began its research by investigating 30 possible candidates that had been found by various groups around the world that are also on similar quests. In addition to performing a chemical analysis of each star, they also studied their respective orbits before coming to the conclusion that HD 162826 was the one that had been born from the same gas and dust system as our sun.
Coincidentally, McDonald Observatory astronomers in West Texas have been studying HD 162826 for over 15 years - While they had no clue it was related to our sun, they do know that it does not have any hot Jupiter-sized planets orbiting close to the star. This however does not rule out the possibility that HD 162826 hosts some earth-size planets that harbor alien life.
While the find is certainly exciting, the team, who plan to publish their study in the June 1st edition of the Astrophysical Journal, believes this is just the first of many siblings our sun has. Professor Ramirez theorizes that 4.5 billion years ago, the sun was part of a cluster of a thousand or perhaps even hundred thousand stars. The cluster has since broken away and scattered to various parts of the Milky Way and mingled with the billions of other stars - Some like the HD 162826 have remained relatively close, whilst others are much farther away.
Though they will probably never be able to locate them all, if enough of the siblings can be found, the research team's 'dynamics specialists' will be able to run each star's orbits backwards in time and locate the place where they intersect. This will help solve the age-old mystery of how and where the sun was 'born'. According to the scientist, finding out what part of the galaxy we came from, may provide them with some clues about how our planet became hospitable to life.
Ramirez also believes that this may be the best way to locate other planets that can harbor life. He says that when the stars were in a dense cluster, massive collisions may have knocked off planetary chunks, and caused asteroids to travel between solar systems and possibly bring along building blocks of life. If that is true, there may be a other few siblings that have earth-like planets orbiting around, complete with aliens!
Resources: dailymail.co.uk, sciencedaily.com, gizmag.com