German astronaut Alexander Gerst says he has a lot to learn before his next mission to the International Space Station in 2018. It will be his first as ISS Commander. What exactly will he have to do?
Granted, Alexander Gerst has been to space before. His first time was for the Blue Dot mission, when he spent six months between May and November 2014 at the International Space Station (ISS).
Gerst racked up 166 days in space. It's more than most of us could ever dream. He says this experience will stand him in good stead for his next mission in 2018. And yet he says he has a lot to learn.
His training started in March - before it was decided Gerst would take command of the ISS in two year's time and become the first German astronaut to do so.
German Chancellor Angela Merkel says it's significant to have "a man like Alexander Gerst" as our "ambassador" in space.
But what exactly does a commander have to do?
Call the shots?...
Yes, but not all the shots. The Commander is tasked with conducting operations on the ISS as directed by the Flight Director, who runs the show from NASA's Johnson Space Center (JSC) in Houston. The Flight Director heads flight controllers, research and engineering experts and support personnel. The ISS Commander represents the "On-Orbit Management," while the Flight Director is "Ground Management."
It's the ISS Commander's job to organize and lead the crew and for molding a "single, integrated team."
As Gerst undergoes his own training in Russia, he will also have to guide his ISS crewmembers through their training and mission-preparation.
Similarly, when crew return, it will be Gerst's responsibility to ensure they complete standard "postflight activities."
Keep the peace on orbit
The Code of Conduct for the International Space Station Crew states the ISS Commander must "maintain a harmonious and cohesive relationship among the ISS crewmembers," taking into account "the international and multicultural nature of the crew and mission."
This line - and its specific wording - were chosen because it was felt there should be a "zero tolerance" stance on harassment onboard the ISS. When the code was being drawn up, it was argued there should be no reference to an ISS Commander making "use of force." Instead, the commander has "the authority to use any reasonable and necessary means to fulfill his or her responsibilities" - so long as this is consistent with the authority of the Flight Director of course.
However, this left a grey zone. What if the safety of a mission and crew was jeopardized by the actions of a crewmember? Should the ISS Commander use force as a means of restraint? Spending six months or a year in space, cut off from any real contact with life on Earth, can be incredibly stressful. An astronaut could flip out. So it was agreed that the Multilateral Coordination Board, which led discussions on the Code of Conduct, would record in its minutes, but not in the code itself: "In cases where necessary to ensure the immediate safety of the crew members of the ISS, reasonable and necessary means may include the use by the ISS Commander of proportional physical force or restraint."
The ISS Commander has to ensure the safety of the crew - its "health and well-being including rescue and return." The commander must also take necessary action for the "protection of the ISS elements, equipment, or payloads."
Feed social media
Commander Chris Hadfield was arguably the first to exploit the social networks during his five month stay at the ISS between 2012 and 2013. He was the first Canadian ISS Commander and also the first person to record a music video in space, with a cover of David Bowie's "Space Oddity." It catapulted Hadfield into a whole new universe of fame. The video on YouTube has been watched more than 31 million times.
A year later, Gerst made the most of Twitter (@astro_alex), posting spectacular images of Earth often with candid commentary, such as the one about Israel and Gaza.
British astronaut Tim Peake (@astro_timpeake), who is currently at the ISS, has taken up the Twitter bug.
And judging by his number of followers, so have all those interested in daily updates from space. Peake has 625,000 followers. Gerst, who tweets in German and English, hovers at around 286,000 followers.
But all this is likely to change as preparations for Gerst's next mission as ISS Commander ramp up. During his 2014 mission Gerst was keen to share more than his images of Earth. He also shared insights into his scientific work on social media and conducted Q&A sessions via live videocasts with children in German schools. He says he's excited about getting back to the ISS to do more experiments in weightlessness, and medical research, and no doubt he'll want to share that too. The question is whether his new role as commander will allow him all the time he needs for playing in the lab.