Explained: Why Russian cosmonauts cancelled the ISS spacewalk

Ground crew spotted fluid leaking from the Roscosmos Soyuz MS-22 spacecraft docked to the Rassvet module on the International Space Station as  Sergei Prokopyev and Dmitry Petelin were preparing for their spacewalk. A former cosmonaut said a micrometeorite entering the craft’s radiator may be to bla

Wednesday on the International Space Station saw high drama with Russian cosmonauts cancelling their space walk at the last minute.

This came after ground team spotted an unknown liquid leaking from the Soyuz MS-22 spacecraft –– a development that could potentially jeopardize a return flight to Earth by three crew members.

But what happened? And what was the liquid? Let’s take a closer look:

What happened?

According to NASA, an external leak was detected from the Roscosmos Soyuz MS-22 spacecraft docked to the Rassvet module on the International Space Station.

Dramatic NASA TV images showed white particles resembling snowflakes streaming out of the rear of the vessel for hours.

NASA said the leak had occurred on the “aft end” of Soyuz MS-22, which is secured to the ISS.

Soyuz MS-22 flew Russian cosmonauts Sergei Prokopyev and Dmitry Petelin and NASA astronaut Frank Rubio to the ISS on 21 September, as per NASA.

Prokopyev and Petelin had been making preparations for a spacewalk on Wednesday when the leak was discovered.

As per India Today, the cosmonauts restored airlock pressure, removed their spacesuits and re-entered the space station.

“The crew reported the warning device of the ship’s diagnostic system went off, indicating a pressure drop in the cooling system,” Roscosmos said.

The planned Roscosmos spacewalk was cancelled to allow time to evaluate the fluid and potential impacts to the integrity of the Soyuz spacecraft, the agency said.

Russia’s space corporation Roscosmos and the US space agency said the leak on the Soyuz MS-22 spacecraft did not pose any danger to the astronauts and cosmonauts aboard the ISS.

“The crew members aboard the space station are safe, and were not in any danger during the leak,” NASA said.

It said ground teams were evaluating “the fluid and potential impacts to the integrity of the Soyuz spacecraft.”

“NASA and Roscosmos will continue to work together to determine the next course of action following the ongoing analysis,” NASA said.

Why did this happen?

The TASS news agency quoted Sergei Krikalev, a former cosmonaut who heads the crewed space flight program for Roscosmos, as saying that the leak may have been caused by a micrometeorite striking Soyuz MS-22.

“The cause of the leak may be a micrometeorite entering the radiator,” TASS quoted Krikalev as saying. “Possible consequences are changes in the temperature regime.”

“No other changes in the telemetric parameters of either the Soyuz spacecraft or the (ISS) station on the Russian or American segments have been detected,” Krikalev said.

“At the moment, all systems of the ISS and the ship are operating normally, the crew is safe.”

“When you see it leaking fluid like that, you know something very, very bad is happening,” Terry Virts, a retired NASA astronaut who flew to the station in a Soyuz capsule in 2014, told NPR.

As per India Today, Russian cosmonauts on 25 November cancelled their spacewalk after problem with coolant pumps on their spacesuits.

What happens next?

NASA and Roscosmos are coordinating external imagery and inspection plans to aid in evaluating the external leak location, the space agency said.

Plans for an additional inspection of the Soyuz exterior using the station’s Canadarm2 robotic arm are underway, NASA said.

As per NASA, the crew on Thursday completed normal operations including participating in science investigations and research.

A Roscosmos spacewalk scheduled for 21 December has been indefinitely postponed as the team continues its investigation of the Soyuz spacecraft.

There are currently four other astronauts and cosmonauts aboard the space station in addition to Rubio, Prokopyev and Petelin.

Soyuz MS-22 is scheduled to bring them back to Earth in March.

As per NPR, the craft is a key piece of safety hardware.

Marcia Smith of Space Policy Online told the outlet “you have to have a way to get off the space station if there’s an emergency.”

“There has been pretty much an ironclad rule since the space station got up there that you can only have as many people on board the space station at any one time as you have lifeboats to get them off,” Smith added.

If it remains unavailable, another vessel would have to be sent to the ISS to bring back the crew.

NASA astronauts Josh Cassada and Nicole Mann, Japanese astronaut Koichi Wakata and Russian cosmonaut Anna Kikina were flown to the ISS in October aboard a SpaceX spacecraft.

Space has been a rare avenue of cooperation between Moscow and Washington since the start of Moscow’s assault on Ukraine in February, and ensuing Western sanctions on Russia that shredded ties between the two countries.

The ISS was launched in 1998 at a time of increased US-Russia cooperation following their Space Race competition during the Cold War.

With inputs from agencies

This article originally appeared on https://www.firstpost.com/ and was reproduced here with permission