So, in August, we got word of the discovery of the fastest asteroid in our solar system. We are talking about a piece of rock about 1 km (0.62 miles) in diameter that has the “Shortest orbital period of all known asteroids in the solar system”, circling the Sun every 113 days. That’s about three times a year, according to our schedule.
The rock was discovered a few months ago by Scott S. Sheppard of the Carnegie Institution of Science using data collected by Ian Dell’antonio and Shenming Fu of Brown University. For the task at hand, they used the Víctor M. Blanco telescope from the Inter-American Observatory of Cerro Tololo (CTIO) in Chile. It would be a 4-meter aperture hardware that also includes the 570 megapixel Dark Energy Camera (DECam). By all accounts, it is a powerful camera, and during the twilight periods of the last days of summer, it proved essential in locating and tracking the asteroid.
Called 2021 PH27, the rock has two possible origins. It either comes, like most other things like this, from the asteroid belt that rotates between Mars and Jupiter, or it was initially a comet from the outer edges of the solar system that somehow got trapped. “in a shorter period orbit closer when passing near one of the terrestrial planets.For now, scientists prefer the latter theory, given the orbital tilt (32 degrees) of the rock.
PH27 was found to take an orbit which, on its closest approach to the Sun, brings it only 20 million km (12 million miles) from the surface of the flaming furnace, while the widest axis of the elliptical orbit is 70 million km (43 million miles). In its movements, it crosses the orbits of our closest neighbors to the Sun, Mercury and Venus.
Now, repeatedly approaching the extremely hot surface of the Sun could end up destroying the asteroid completely – scientists have calculated the surface temperature of PH27 at its closest approach to be at least 500 degrees Celsius (approx. 900 degrees Fahrenheit), hot enough to melt lead.
If that does not happen, in millions of years it has a very high chance of colliding with Mercury, Venus or the Sun.
You might be wondering how spotting an asteroid close to the Sun that has no chance of hitting us helps humanity in the long run. Well, remember how we started all of this with NASA’s estimate of how many near-Earth asteroids we know of? Then consider the fact that the same NASA says there are 15,000 more asteroids that we don’t know anything about.
Spotting PH27 was a particularly tricky affair (more on that here), not least because of the glare from the Sun and the size of the asteroid. But the lessons learned with it could help improve our habits and, in so doing, empower one of the races on this planet, for the first time in history, to avoid extinction.
“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, away from the sun, “ concluded after the discovery of the Sheppard.