(CNN)Veteran former astronaut Scott Kelly tells CNN he is backing off his high-profile Twitter war with the head of the Russian space agency, following a warning from a NASA official that such attacks are "damaging" to the International Space Station mission.
Former astronaut to back off Twitter war with head of Russian space agency
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The warning came in an email, obtained exclusively by CNN, that was sent to all former US astronauts last week from a current NASA official who urged caution before "attacking our Russian partners."
The war in Ukraine has pushed some former NASA astronauts, including Kelly, to speak out against the head of Russia's space agency, and it's putting NASA in a tough spot as it works to preserve its 20-year partnership with the Russians at the International Space Station.
"As Americans, each of us enjoys freedom of speech and you are all empowered to speak your mind," the email reads. "However, please know that as former NASA astronauts, your words carry additional weight and attacking our Russian partners is damaging to our current mission."
CNN obtained a copy of the email with the stipulation that the name of the high-ranking NASA official not be revealed.
On the same day the email went out, Kelly, one of NASA's most famous former astronauts, was blocked on Twitter by Roscosmos Director General Dmitry Rogozin after Kelly criticized both Russia's invasion of Ukraine and Rogozin's repeated threats to pull out of the International Space Station.
"Get off, you moron!" Rogozin said in a quickly deleted Tweet. "Otherwise, the death of the International Space Station will be on your conscience."
"Dimon, why did you delete this tweet?" Kelly replied via Twitter in Russian. "Don't want everyone to see what kind of child you are?"
Kelly told CNN in an interview last week that he felt compelled to speak out after Rogozin shared a Roscosmos-produced video showing two Russian cosmonauts floating inside the space station and waving goodbye to NASA astronaut Mark Vande Hei, who is supposed to return to Earth with them on a Russian Soyuz spacecraft on March 30.
But after receiving the email from the NASA official, Kelly told CNN that he's decided to refrain from engaging in another Twitter fight with Rogozin, something he hinted at in an op-ed on Tuesday.
"Yes, I saw the email and backed off Rogozin. I didn't have to, but I respect NASA, NASA's position and the (official) that sent it," Kelly told CNN, though he intends to keep opposing the war in fluent Russian for his more than 5 million Twitter followers.
NASA's position is that it wants the International Space Station to continue to be "the flagship model for international cooperation."
"For over 20 years, the International Space Station partnership has operated successfully, and nothing has changed in the last three weeks," Joel Montalbano, the manager of NASA's International Space Station program, said at a Monday news conference. "We are aware of what's going on, but we are able to do our jobs to continue operations."
That includes the successful completion of a nearly seven-hour long spacewalk on Tuesday by NASA astronauts Kayla Barron and Raja Chari. While inside the space station, Vande Hei surpassed Kelly's record for the single longest spaceflight by a US astronaut.
"Congratulations!" Kelly told Vande Hei on Twitter. "Broken records indicate progress. Looking forward to seeing you safely home soon. Ad astra!"
Vande Hei, who launched to the space station in April 2021, is expected to log a total of 355 days in orbit by the time he returns to Earth on a Russian Soyuz spacecraft and lands in Kazakhstan. He'll travel home on a Gulfstream jet, as other US astronauts have before him.
"I can tell you, for sure, Mark is coming home on that Soyuz. We are in communication with our Russian colleagues. There's no fuzz on that," Montalbano said Monday.
Despite tensions remaining white hot between the US and Russia on Earth, the International Space Station continues to be a beacon of diplomacy between the teams in mission control and the fliers on board.
"Are they aware of what's going on on Earth? Absolutely," Montalbano said. "But the astronauts and cosmonauts are some of the most professional groups you'll ever see. They continue to operate well and there's really no tensions with the team. This is what they've been trained to do -- a job -- and they're up there doing that job."
NASA declined to specifically address the email, but NASA Administrator Bill Nelson acknowledged the "substantial" challenges that the agency is currently facing.
"Despite challenges on Earth -- and they are substantial -- NASA is committed to the seven astronauts and cosmonauts on board the International Space Station. NASA continues the working relationship with all our international partners to ensure their safety and the ongoing safe operations of the ISS," Nelson said.