This asteroid only needs 113 days to go around the Sun: only the planet Mercury goes faster
Discovering new asteroids roaming the solar system is not exceptional, we have millions of these small stellar bodies orbiting the sun and we have been cataloging them for decades. But 2021 PH27, the asteroid they have recently discovered at the Carnegie Institution for Science, it has several quirks that make it almost unique.
This rock of about 1 km in diameter takes only 113 days to go around the sun, at a distance of 20 million from the star. That makes it the asteroid with the shortest known orbit in our solar system, and the second if we take into account the 88-day orbit of the planet Mercury.
An asteroid that will slowly disintegrate from getting too close to the Sun
The discovery was made by Scott Shepard, who comments in 9News that “asteroids of this size are seldom seen” with orbits so close to the Sun. It only crosses the orbits of Mercury and Venus, the Earth is already far away by 2021 PH27.
Shepard has two theories for the origin of this asteroid. Either it is a comet whose tail has completely evaporated or it is an ancient tenant of the asteroid belt that was deflected by the gravitational pull of the inner planets of the solar system. Regardless of one or the other, the teacher estimates a temperature of 900º C by the time 2021 PH27 is closer to the Sun. And since this temperature is capable of melting lead, it is suspected that the asteroid is made up of rocks and metals that are more resistant to high temperatures.
2021 PH27 does not have a very promising future. It is predicted that sometime during the next 20 million years (a “little while” in the great timescale of the universe), planetary gravity and the heat of the Sun fragment the asteroid little by little until you finish disintegrating it altogether. And that’s if it doesn’t end up colliding with Mercury or Venus, of course.
Until that happens, 2021 PH27 becomes part of a short and exclusive list of so-called asteroids shoot, formed by those bodies whose orbits are within the terrestrial orbital path. It is an area that is relatively close to us, which due to the brightness of the Sun we have not explored much compared to the rest of the sky.