The most famous asteroid in the solar system spotted, flies closer to the Sun than Mercury • The Register

Astronomers have discovered the fastest asteroid orbiting the Sun to date, a kilometer-wide space rock that circles our star every 113 Earth days.

The asteroid, known as 2021 PH₂₇, was recorded on August 13 by Scott Sheppard of the Carnegie Institution for Science in the United States. He noticed the object in images taken by Ian Dell’antonio and Shenming Fu of Brown University using the 570-megapixel dark-energy camera at the Victor M. Blanco Telescope in Chile.

Rather than living in the asteroid belt between Mars and Jupiter, PH₂₇ has been observed much closer to our star. Indeed, during its orbit, PH₂₁ approaches the Sun than Mercury: the shortest distance from the rock to the star is only 20 million kilometers (12 million miles), at which point its surface has a lead melting temperature of 480 ° C (900 ° F). PH₂₁The 113-day orbit has a semi-major axis of 70 million kilometers (43 million miles) and intersects the orbits of Mercury and Venus.

David Tholen of the University of Hawaii calculated the pH₂₇around the Sun from its position in the images. Over the next few days, as news of the strange and exciting rock emerged, astronomers from other observatories used Tholen’s calculations to point their telescopes where the asteroid should be, and they also caught sight of PH₂₇.

“Although telescope time for astronomers is very precious, the international nature and love of the unknown make astronomers very willing to bypass their own science and observations to follow exciting new discoveries like this,” Sheppard said Monday.

The race was on to confirm Sheppard and Tholen’s findings before the space rock disappeared from view.

“Because the object was already in the Sun’s glare and was heading more towards it,” Tholen said, “it was imperative that we determine the object’s orbit before it was lost behind our star. I assumed that for an asteroid of this size to stay hidden for so long, it must have an orbit that keeps it so close to the Sun that it is difficult to detect from Earth’s position.

From PH₂₇ lives so close to the Sun and has relatively low mass, it experiences general relativistic effects more than any other known object in the solar system, according to the US National Science Foundation’s NOIRLab. Its orbit is also unstable, and astronomers estimate that in a few million years, it will either be destroyed in a collision with Mercury or Venus, or burnt by getting too close to the Sun, or driven from its orbit by other bodies. .

“Most likely PH₂₇ has been dislodged from the main asteroid belt between Jupiter and Mars and the gravity of the inner planets has shaped its orbit in its current configuration, ”said Sheppard.

“Although, based on its large tilt angle of 32 degrees, it is possible [it] is an extinct comet from the Outer Solar System that ventured too close to one of the planets as its path of travel brought it closer to the Inner Solar System.

“Understanding the asteroid population within Earth’s orbit is important to complete the census of near-Earth asteroids, including some of the more likely Earth impactors that may approach Earth during the day and which cannot be easily discovered in most surveys that observe at night, far from the Sun, ”he added.

Astronomers will be able to see the asteroid better when it is not blocked by Earth’s Sun in 2022. ®