Astronomers from the Max Planck Institute for Solar System Research and the University of Göttingen in Germany have determined that a star known as Kepler 11145123 is the closest thing to a perfectly round sphere ever measured. The star, which is located 5,000 light-years from Earth, was studied with NASA’s Kepler telescope for 51 months, from 2009 to 2013. Using a technique called asteroseismology, astronomers were able to determine that the distant star’s equatorial and polar diameters differ by a mere 3.7 miles (6 km), even though the star is 1.86 million miles (3 million km) in diameter -- about twice as wide as the Sun.
Honoring a 17th-century astronomer:
- Stars, planets, and other celestial bodies bulge slightly at their equators due to centrifugal force. Generally speaking, the faster these objects spin, the larger the bulge at the equator.
- Kepler is a space observatory launched by NASA in 2009 with the aim of discovering Earth-size planets orbiting other stars.
- The telescope and star described above were both named after Johannes Kepler, a 17th-century German mathematician, astronomer, and astrologer best known for his formulation of the laws of planetary motion.