A Chinese missile weighing 22 tons falls to the ground. Where will you land?

When asked, “What’s up?” This weekend, here’s your answer: Long March 5B, a nearly 44,000-pound rocket object heading toward Earth.

But scientists are elements of when and where this wreckage is – from last Sunday’s China launch From the Wentian space module – it will land. Aerospace Corporation has released its latest projected wreckage tracks — with the disclaimer that it’s still too early to be certain.

Experts believe that 20 percent to 40 percent of the rocket’s massive mass will survive its fiery journey through Earth’s atmosphere to the planet’s surface, but not in one piece. Seventy percent of the planet is covered in ocean, so odds are that whatever is left of the rocket will fall into the water, but that’s not guaranteed.

Shrugging shoulders in response to potential dangers from the Long March 5B wreck is nothing new. About 70 percent of rockets that go out of orbit and re-enter Earth’s atmosphere do so in an uncontrolled way, said Aaron Polley, co-director of the Outer Space Institute and a planetary astronomer at the University of British Columbia, and rocket debris is just part of that risk.

In April, a 6- to 10-foot metal ring fell on a village in the Indian state of Maharashtra. In 2020, a 39-foot metal pipe fell on two villages in Ivory Coast. In 2016, two rocket fuel tanks landed on the islands of Indonesia. Earlier this month, parts of a SpaceX box capsule fell into grasslands in New South Wales, Australia.

“Every time we launch rockets, we roll the dice,” Polly said. “The problem is that we roll the dice too many times.”

A rocket is the transport ship for anything put into orbit, including individual satellites, satellite towers, telescopes, engineering projects, and research units. In 2021, there were more than 130 successful orbital missile launches globally – a record – and 2022 is on track to deliver more as space development rates soar.

“In the future, we may have companies launching rockets to build their own space stations, whether it’s for tourism or for manufacturing in orbit,” Polly said.

Missile trajectories can take many forms. Oftentimes, they disintegrate gradually during ascent, eliminating heavy boosters or empty fuel tanks in a controlled process called staging. When staging occurs in the subtropical region – where Earth’s gravity still has full or almost complete effect on falling instruments – launch teams can plan precisely where they will land (over the ocean).

Other mission paths require that some stages of the rocket be abandoned in Low Earth Orbit (LEO) — an area considered to be between 180 and 1,250 miles above Earth — where they are left to drift, effectively, as space junk.

The technology is there to reduce the risk. Just not everyone uses it.

This is not a technical problem. Some rockets, like SpaceX’s Falcon 9, have combustible engines, which can direct re-entry to an uninhabited place (by humans) on Earth, sometimes even complete return flights with ready and waiting landing pads.

But not all missiles are equipped with these technologies, and even if they are, “there are additional expenses associated with recovery,” Polly said. “The customer might decide on a cheaper option, or the launch team might decide it’s easier to dump the object into orbit.”

So, the rocket bodies – including the particularly massive Long March 5B rocket, which was not equipped with re-ignition engines – were left to litter in low Earth orbit. It’s a political decision that many countries, including the United States, seem okay with.

Currently more than 1,000 rocket objects and thousands of satellites flow through low Earth orbit, completing revolutions around the Earth every 90 to 120 minutes.

These slow-burning orbital flights — prominently tracked and shared online by the Aerospace Corporation, an independent government-sponsored non-profit organization — are gradually being slowed down by drag, the same aerodynamic force that naturally collides with an airplane or race car. , and fall down. on the earth.

“It’s kind of funny, because orbit is nothing more than falling in the direction of something and constantly losing it. And then eventually, the gas clouds make it so, no, it’s going to hit this time.”

Where space debris isn’t always left to chance

The final landing points of many of these unattended entrances are not always random – many are launched and land around the equator.

Studying the orbital trajectories of more than 1,500 de-orbiting rockets in the past 30 years, Polly and a team of researchers at the University of British Columbia estimated that there was a 10 to 20 percent chance of casualties due to missile debris. .

That’s a far cry from the 0.01 percent risk threshold that the US applies to its launches, an assessment of losses often conceded. “To my knowledge, there is no paper trail of the decision-making process that led to this [0.01 percent] The number was applied to launches and re-entries,” Polly said.

“But we can’t portray people in space as evil,” said Timiebi Aganaba, associate professor and chief global future scientist at Arizona State University who specializes in environmental and space management. “[When the policies on space development were set], there were very few launches; It’s not something anyone would have talked about 10 years ago.”

But now, with space still being commoditized and rockets flying more frequently, both Bole and Aghanaba agree that rocket debris is a teamwork problem. Polly said the solution would require the international community to come together and agree on risk mitigation regulations.

How and when these rules will be established and followed must be seen. It may take until “someone wins the lottery, so to speak,” Polley said, from being unfortunately exposed to space debris. “Odds are it won’t be you, but someone will.”

This article has been updated. Thanks to Lillian Barclay for the edit version of this article.

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