Satellites to have ‘really close encounter’ this week. But what if they collide?

Two retired satellites are going to have a close encounter Wednesday, scientists say. They could even collide about 560 miles above Pittsburgh, Pennsylvania.

LeoLabs, a space debris tracking and collision prevention service, says a space telescope and a science payload will likely come within 50 to 100 feet of each other at about 6:40 p.m. ET on Wednesday, ScienceAlert reported.

The distance is “especially alarming,” LeoLabs said on Twitter. Scientists agree the possible collision would be very dangerous.

“This is a really, really close encounter,” space archaeologist Alice Gorman of Flinders University told ScienceAlert. “And if this does actually come to pass, there’s potentially a large amount of debris that will be created. I would say this is one of one of the most dangerous possible collisions that we’ve seen for some time.”

Both objects are out of commission and retired, so there is no way to communicate with them, Science Alert reported. The space telescope was launched in 1983, and the payload launched in 1967, according to LeoLabs.

“We are monitoring a close approach event involving IRAS (13777), the decommissioned space telescope launched in 1983, and GGSE-4 (2828), an experimental US payload launched in 1967,” LeoLabs tweeted Monday.

LeoLabs said the chance of collision is about 1-in-1,000.

Experts at The Aerospace Corporation, however, found a 1-in-10 chance of collision, according to Business Insider.

“This is one of the closest that we have ever seen,” Roger Thompson, a senior engineering specialist at The Aerospace Corporation, told Business Insider. “LeoLabs has pointed out a very dangerous conjunction.”

What happens if the satellites collide? Business Insider reported that the objects could break apart and create debris that would orbit Earth, threatening the International Space Station.

“If such orbital junk were ever to get too plentiful and out of control, it could cut off our access to space for hundreds of years,” Business Insider said.

If the satelllites collide, “observers on the ground in Pittsburgh would likely see a bright flash in the sky like a shooting star,” Thompson told Business Insider.

Luckily for Earth, though, there’s no clear threat to anyone on the planet, ScienceAlert said, because any debris would burn up before making it to the ground.

“Events like this highlight the need for responsible, timely deorbiting of satellites for space sustainability moving forward,” LeoLabs tweeted. “We will continue to monitor this event through the coming days and provide updates as available.”