Astronomers discover new star through Galileo's technique

Washington, Dec.10 (ANI): Astronomers have reportedly discovered a faint star orbiting the Big Dipper-Alcor B-using a novel technique known to 17th century astronomer and scientist Galileo

According to a new paper published in The Astrophysical Journal, one of the stars that makes the bend in the ladle's handle, Alcor, has a smaller red dwarf companion.

The newly discovered Alcor B orbits its larger sibling Alcor and was caught in the act with an innovative technique called "common parallactic motion" by members of Project 1640, an international collaborative team that includes astrophysicists at the American Museum of Natural History, the University of Cambridge's Institute of Astronomy, the California Institute of Technology, and NASA's Jet Propulsion Laboratory.

"We used a brand new technique for determining that an object orbits a nearby star, a technique that's a nice nod to Galileo," says Ben R.Oppenheimer, Curator and Professor in the Department of Astrophysics at the Museum.

"Galileo showed tremendous foresight. Four hundred years ago, he realized that if Copernicus was right-that the Earth orbits the Sun-they could show it by observing the "parallactic motion" of the nearest stars. Incredibly, Galileo tried to use Alcor to see it but didn't have the necessary precision," added Oppenheimer.

If Galileo had been able to see change over time in Alcor's position, he would have had conclusive evidence that Copernicus was right.

Parallactic motion is the way nearby stars appear to move in an annual, repeatable pattern relative to much more distant stars, simply because the observer on Earth is circling the Sun and sees these stars from different places over the year.

Alcor is a relatively young star twice the mass of the Sun. Stars this massive are relatively rare, short-lived, and bright. Alcor and its cousins in the Big Dipper formed from the same cloud of matter about 500 million years ago, something unusual for a constellation since most of these patterns in the sky are composed of unrelated stars.

Alcor shares a position in the Big Dipper with another star, Mizar. In fact, both stars were used as a common test of eyesight-being able to distinguish "the rider from the horse"-among ancient people.

The team plans to use parallactic motion again in the future. (ANI)