What If Space Junk Falls To Earth?

 

What If Space Junk Falls To Earth, has space debris fallen to Earth increased? How dangerous is it to people or property?

Earlier this year, there were two separate incidents of space debris falling in unexpected places on Earth.

A Chinese Long March 5B rocket was reported to have crashed in Australia's New South Wales region in July after it went out of control and re-entered Earth's orbit. They have now been confirmed to be debris from the SpaceX Crew-1 mission.As the space industry continues to grow, it is safe to say that such incidents will only increase and pose a threat. can But how big a threat could space debris fall to Earth be?

Space debris refers to systems sent by humans into space, whose malfunctioning or redundant parts fall to Earth. It can also be a satellite that has reached the end of its life (as the International Space Station will reach the end of its operational life in 2031) or parts of a rocket system that have completed their mission in space. So far, China has launched three Long March 5B rockets into space and all three have been deliberately launched into uncontrolled orbits. This means that it is not known when and where they will fall.

As for the SpaceX debris that landed in the Australian Snowy Mountains, it can be said that SpaceX launches its rockets out of orbit with full control and designs them in such a way. When they re-enter Earth's atmosphere, they burn up. But as you saw in the latest news, these things don't always go according to plan.

So how dangerous is space debris really?

As far as we know, only one person on Earth has been hit by space debris. Lottie Williams, a resident of the US state of Oklahoma, was hit by a piece of shrapnel on her shoulder in 1997 but was unharmed. The debris was about the size of his hand and is believed to have come from a Delta-2 rocket. Ms Luti picked him up, brought him home and reported him to the authorities the next day.

But as more and more systems, rockets and space stations go into space, there are growing concerns that they could come back down and hit people or property. This is especially true of large and uncontrollable objects such as Long March 5B.

This model of rocket has been launched three times. The first re-entered Earth's atmosphere on May 11, 2020, and parts of it fell on two villages in Ivory Coast. The second one fell near the Maldives on May 9, 2021, while the third one re-entered the Earth's atmosphere over Indonesia and Malaysia and its debris fell around those islands.

So should we be worried?

The chances of someone being injured by space debris are very low and are estimated to be about one in ten thousand. It can happen to anyone anywhere in the world. However, the chances of it happening to a particular person (like you or me) are on the order of one in a trillion.

 

Can we prepare to avoid?

Two questions come to mind: Can we predict debris re-entry into Earth's atmosphere, and what can we do to reduce the risk?

Let's start with predictions. In this case, it can be extremely difficult to predict where an uncontrolled object in orbit will enter Earth's atmosphere. As a general rule of thumb, the expected reentry time will be ten percent of the orbital time. This means that predicting an object's reentry in ten hours would have an uncertainty margin of about one hour. So if an object is orbiting the Earth every 60-90 minutes, it can enter anywhere at any time.

Improving this uncertainty margin is a major challenge and requires much research. Even so, it is unlikely that we will be able to accurately predict the re-entry point of an object at a distance of 1,000 km (621 miles).

Ways to reduce risk

Mitigating risk is a challenge, but there are certainly options.

First, all objects sent into Earth orbit should be designed in such a way that they fall out of orbit in an unpopulated area. This is usually the SPOUA (South Pacific Uninhabited Area), also known as the 'spacecraft graveyard'. This involves carefully designing components so that they can be re-entered within the Earth's range. They should be completely broken upon entering. If everything burns up on impact with the Earth's upper atmosphere, then there will be no significant danger left.

There are already some guidelines for reducing the risk of space debris, such as the United Nations Guidelines for the Long-Term Sustainability of Outer Space Activities, but their methodology has not been defined. Furthermore, How do these guidelines apply internationally, and who can enforce them? Such questions are still unanswered.

In summary, should you worry about being hit by space debris? So the answer, for now, is no. Is more research on space debris necessary for the future? So the answer is absolutely yes.