Asteroid Pen: How much impact is possible? Determines the risk of the aircraft being attacked in 2185 via the “keyhole”

A “keyhole” concludes: NASA researchers have reduced the orbit of the asteroid Pennu near Earth – the risk of the impact that comes with it. Thus, in 2135 it can be determined whether the closest flying aircraft hit any of the strip passages at an altitude of about 500 meters. If it reaches the “keyhole” in 20135, it will hit Earth in September 2182. However, the probability is only 1 in 2,700.

It is about 500 meters high and weighs about 60 million tons Asteroid Pen One of the few astronomical bodies near Earth that is currently classified as a hazard to Earth. This is because in its 1.2 year orbit this piece repeatedly crosses the Earth’s orbit. Every few years it gets closer to our planet. For this reason, NASA, among other things, chose Pennu as the target for the OSIRIS-Rex mission, during which a precision asteroid and A sample Has taken its surface.

The year 2135 is decisive

Now a team led by David Fornocia from NASA’s Jet Propulsion Laboratory has evaluated data collected by the spacecraft over two years and obtained new information about Penn’s flight path and impact risk. “The Osiris Rex mission has given us an extraordinary opportunity to more accurately predict where Pennu will be when he comes close to Earth for more than a century,” said Kelly Fast of NASA.

It is known that in 2135 this asteroid will be closer to the Earth than the orbit of the Moon. There is no danger of impact, but the influence of gravity on Earth can change its orbit, causing it to strike our planet in its later orbit. Whether this happens depends on whether the Penn 2135 flies in one of the “keyholes” – locations close to the Earth, which could push the Earth’s gravitational pull in a collision course.

Impact Risk 1: 1,750

New calculations based on OSIRIS-Rex data now show: Penn will definitely lose 24 of the 26 key “key holes”. However, Fornocia and his team could not completely rule out an impact by 2300. According to her, the risk is 0.057 percent or 1: 1,750. This puts the pennum on top of the pennermo level, which shows the risk of impact. The asteroid (29075) at about one kilometer in size 1950 DA only has a similarly high list, but it does not pose a risk until 2880.

NASA researchers report that September 24, 2182 had the most impact so far – if so, the probability of an earthquake on this day is 0.037 percent, or 1: 2,700. It remains to be seen whether 2037 will be at this value or will change further. This is because Pennu is getting very close to Earth again, and his orbital data can be compared again with the help of telescopes.

How the researchers limited the risk of Penn’s impact.© NASA / GSFC

Yarkovsky effect: The mass of three grapes

The so-called Yarkovsky effect is one of the factors influencing the risk assessment that Fornochia and his colleagues have explored in more detail. This is because solar radiation heats the sides of the asteroid to varying degrees. Depending on the speed of rotation and rotation, it is easily deflected inward or outward by this radiant pressure. This is enough to significantly change the risk of impact, especially when it comes to the “keyholes” that determine the path. This includes Asteroid Apophis Be the case

For Pennu, the researchers determined the Yarkovsky effect using data from OSIRIS-Rex as accurately as possible. Conclusion: “The effect on the penny is approximately equal to the mass of three grapes,” reports co-writer Steve Chesley from JBL. “It’s incredibly small, but significant when it comes to the risk of impact in the future for a few decades to centuries.”

Did OSIRIS-Rex change the path of the pen?

Another factor that scientists have tested is the OSIRIS-Rex mission. This is because the spacecraft used a gas nozzle when taking samples to shake the surface of the spacecraft slightly. Fortunately, the team was able to give all the clarity: “The force exerted on Penn at this event was small, even compared to other weak influences,” says Richard Burn of NASA’s Goddard Space Flight Center. “She didn’t change Rico’s impact on Pennu.” (Icarus, 2021; doi: 10.1016 / j.icarus.2021.114594)

What: NASA

13. August 2021

– Natja Bodybreaker