NZ radar could reveal possible space junk collision

A New Zealand-based radar will tell scientists if two pieces of space junk - together weighing 2.8 tonnes - collide or narrowly miss each other over Antarctica tomorrow afternoon. Image / LeoLabs Inc

A New Zealand-based radar will tell scientists whether two pieces of space junk - together weighing 2.8 tonnes - will collide or narrowly miss each other over Antarctica tomorrow.

LeoLabs, a company that tracks space junk, is warning of a "high risk" event - a potential collision between a defunct Russian spy satellite and a spent part of a Chinese rocket, just before 2pm Friday.

The company's latest forecast put the chances of Russian Cosmos satellite and the CZ-4C rocket slamming into each other, 991km above the Earth, at more than 10 per cent.

LeoLabs warned the two objects could pass within just 12m of each other at a relative velocity of 14.7km per second, after earlier putting the chance of collision at one in 20.

Whether that collision impact happened would be revealed by LeoLabs' radar at Naseby, in Central Otago.

"Shortly after [time of closest approach], we will have a direct pass of CZ-4C R/B over our Kiwi Space Radar in New Zealand," the company tweeted today.

1/ This event continues to be very high risk and will likely stay this way through the time of closest approach. Our system generates new conjunction reports 6-8x per day on this event with new observation data each time. pic.twitter.com/d3tRbcV2P0

— LeoLabs, Inc. (@LeoLabs_Space) October 14, 2020

"We have scheduled a search mode scan during this time to ensure we only see two objects as expected and hopefully confirm that no new debris is detected."

The possible point of collision was calculated at above the Weddell Sea, just off the coast of Antarctica.

University of Auckland astronomer Professor Richard Easther expected the two objects would either "whizz past each other" or hit.

If that happened, there were fears it could send thousands of new pieces of junk into space, threatening functioning satellites.

"Anything that's in space is both a target and a bullet," he said.

"And when you increase the number of pieces, you're also increasing the likelihood of future collisions."

He saw the possible collision as a "wake-up call" for the space community to be more mindful about the consequences of debris in orbit.

"That means ensuring that satellites are safely de-orbited, or moved out of the way, toward the end of their controllable life."

If the space junk problem couldn't be tackled, the world could be locked into what's called "Kessler Syndrome" - or where entering space becomes too dangerous.

"And even if we don't get the full-on Kessler Syndrome scenario, operating in space will just become much more complex."