One of the brightest, closest stars to the Earth is Altair, located about 15 light-years away. For the first time, astronomers have imaged its surface, getting a better look at this bizarre neighbour.
Unlike the red giant stars that have been imaged to date, Altair is relatively tiny. It only has 1.7 times the mass of our own Sun. It rotates at an amazing speed, with its equator turning at about 300 km/s (186 miles/s), and completing a full revolution in under 10 hours. This high rate of rotation flattens the star out so that it’s 22% wider than it is tall.
These new observations were made using four of the six telescopes at a facility on Mt. Wilson, Calif., operated by the Center for High Angular Resolution Astronomy (CHARA). They have a special instrument that allows them to clean up the distortions created by the Earth’s atmosphere. By using the four telescopes together, they acted as a single instrument with 25 times the resolution of the Hubble Space Telescope.
Original Source: NSF News Release