Why does this keep happening?
Leaks on Leaks
A second Russian spacecraft docked to the International Space Station has sprung a leak in one of its coolant lines, in just a matter of months — the latest episode of chaos, in other words, in Russia's increasingly battered space program.
The latest leak occurred over the weekend, causing a "depressurization" in a cargo spacecraft dubbed Progress MS-21, according to a statement by the Russian space agency Rosocosmos.
Crew on board the ISS weren't in any danger, according to NASA. The agency also noted that "the hatches between the Progress 82 and the station are open, and temperatures and pressures aboard the station are all normal," despite the coolant system leak
That it's the second leak of its kind in a matter of months, on a separate spacecraft, seems on its face to be an extraordinary coincidence.
The leak comes just under two months after a different Russian spacecraft docked to the station, the Soyuz MS-22, started spraying coolant into space in a strikingly similar incident.
Both Russian and NASA officials have said the December leak was likely the result of a micrometeorite impact, but the cause of the second remains unclear.
That's all to say that we have more questions than answers. Roscosmos has remained extremely vague and hasn't elaborated on a possible cause.
The cargo spacecraft was scheduled to undock from the station on Friday to eventually burn up in the atmosphere, along with a bunch of trash stored inside it — which means engineers likely won't have the chance to examine the craft more closely after the fact, as Space.com points out.
For now, we'll have to wait and see if Rosocosmos and NASA decide to postpone MS-21's departure.
READ MORE: Progress cargo spacecraft at ISS suffers coolant leak [SpaceNews]
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