Baby star found close to Earth – Australian Geographic

ASTRONOMERS HAVE DISCOVERED the closest known infant star to our planet, and it wasn’t born until 25 million years after the extinction of the dinosaurs.

The star, called AP Columbae, is closer to Earth than previously thought and is around 40 million years old – a stellar newborn when compared to our own Sun which was created 4.6 billion years ago.

“The star has been known about and studied for the past 15 years, but it wasn’t realised it was so young and so close, until now,” says co-author Simon Murphy, a PhD student from the Australian National University in Canberra. He says that highly accurate measurements from telescopes in Coonabarabran, NSW, and Chile, Hawaii and California, allowed the international team to build a much better picture of the star.

How to measure a star

AP Columbae is classed as a red-dwarf star because it is relatively small – about a third the size of the Sun – and comparatively cool, with a surface temperature of about 3500ºC as opposed to the Sun’s 6000ºC.

To measure the distance of the young star to Earth was relatively simple, Simon told Australian Geographic. As the Earth moved around in its natural orbit, the team observed how the position of AP Columbae changed in relation to stars in the background. “It’s similar to when you’re in a car, and the trees you see on the side of the road move at a different rate to the mountains in the background, depending on how far away they are,” he says. “So with enough observations you can tie down the distance to a nearby star very accurately. But measuring the age is a little more tricky.”

via Baby star found close to Earth – Australian Geographic.