(CNN)A newly discovered asteroid is sticking close to our sun — much closer than our own planet Earth.The asteroid, called 2021 PH27, completes an orbit around the sun every 113 days and comes within 12.4 million miles (20 million kilometers) of our star.That gives this space rock the distinction of having the shortest known orbital period for an asteroid — and only the second shortest orbit around the sun after Mercury, which takes 88 days to complete its orbital journey around our star.
Scott Sheppard, an astronomer at the Carnegie Institution for Science, discovered the asteroid in twilight observations made by Brown University astronomers Ian Dell’Antonio and Shenming Fu on August 13. Dell’Antonio, a professor of physics, and Fu, a doctoral student, took the images using the Dark Energy Camera mounted on the Víctor M. Blanco 4-meter Telescope at Cerro Tololo Inter-American Observatory in Chile.Multiple aspects of the asteroid surprised Sheppard.The asteroid is 0.6 miles (1 kilometer) in size and “very few asteroids this size in the inner solar system likely exist that are unknown,” he said.”2021 PH27 gets so close to the Sun that its surface can reach temperatures of 900 degrees Fahrenheit (482 degrees Celsius), hot enough to melt lead,” said Sheppard via email. “Because of these extreme temperatures, it is unlikely 2021 PH27 is composed of any volatile material, and it is most likely made up of rock with maybe some metal like iron.”
t has an unstable orbit that crosses the orbits of Mercury and Venus as they make their way around the sun. Within a few million years, the asteroid’s orbit will likely cause its doom. The rocky fragment could collide with Mercury or Venus, or the sun itself, or be knocked out of its current position in the solar system.