Phew! 2 big hunks of space junk zoom safely past each other in near-miss - Space.com

Two large pieces of orbital debris — a defunct Soviet navigation satellite and a spent Chinese rocket body — apparently whizzed safely past each other high over the South Atlantic Ocean on Thursday evening (Oct. 15).

The California-based space tracking company LeoLabs alerted the world ahead of time to the close approach, which occurred at 8:56 p.m.

👍CZ-4C R/B passed over LeoLabs Kiwi Space Radar 10 minutes after TCA.

CZ-4C R/B passed over LeoLabs Kiwi Space Radar 10 minutes after TCA.

(CZ-4C R/B is the Chinese rocket body, Kiwi Space Radar is the company's New Zealand tracking array and TCA stands for "time of closest approach.").

The dead Russian satellite and Chinese rocket body have a combined mass of about 6,170 lbs.

A smashup would likely have led to a "significant (10 to 20 percent) increase in the LEO [low Earth orbit] debris environment," astronomer and satellite tracker Jonathan McDowell, who's based at the Harvard-Smithsonian Center for Astrophysics, said via Twitter on Wednesday.

That debris environment is already substantial.

Orbital collisions are not just the stuff of science-fiction films like 2013's "Gravity." In 2009, for instance, a defunct Russian military satellite called Kosmos 2251 slammed into the operational communications satellite Iridium 33, generating 1,800 pieces of trackable debris by the following October (and many others too small to monitor).

The debris problem will continue to grow as more and more satellites launch to space — a trend that's accelerating, thanks to continuing decreases in the costs of both launch and satellite development.

But space debris is still a big problem," McDowell said in another tweet on Thursday night.