Nasa’s SpaceX Crew-2 mission will be launching four more astronauts to the International Space Station (ISS) on the SpaceX Crew Dragon on Earth Day—this Thursday, April 22.

The astronauts include Shane Kimbrough and Megan McArthur and two international partnerships, Japan Aerospace Exploration Agency (JAXA) astronaut Akihiko Hoshide and ESA (European Space Agency) astronaut Thomas Pesquet.

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The Crew-2 astronauts are set to join other members of Expedition 65 on the ISS, for a six-month mission that places major emphasis on the research of tissue chips in space. These chips are small models of human organs that contain multiple cell types that behave the same way as they would in the human body. The idea being that the use of said chips could make it possible to identify safe and effective therapeutic drugs (both oral drugs and vaccines) on a much more rapid level.

Essentially, ageing and disease develops much more quickly in microgravity—which means that scientists can observe specific diseases that may affect organs in the human body at a much faster rate than if they were developed on Earth.

“We know that cells communicate with each other and that this communication is critical for proper functioning,” Liz Warren, senior program director at the ISS US National Laboratory, explained in a press release.

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“We don’t fully understand why, but in microgravity, cell-to-cell communication works differently than it does in a cell culture flask on Earth. Cells also aggregate or gather together differently in microgravity. These features allow cells to behave more like they do when inside the body. Thus, microgravity appears to provide a unique opportunity for tissue engineering.”

The Crew-2 mission will also involve updating the station’s solar power system by installing compact solar panels that “roll open like a huge yoga mat.” The technology, which was developed back in 2009, will supplement the station’s existing rigid panels.

The exciting launch will take place this Thursday, April 22 at the Kennedy Space Center in Florida. Tickets for the VIP launch viewing sites have already been sold out but off-site viewpoints like the Playalinda Beach at Canaveral National Seashore make a decent spot to watch in person as well.

The event will also be live-streamed on Nasa TV—which is available to watch for free via Nasa social media accounts and the official Nasa website. Note that prelaunch interviews and various other virtual events will also be on Nasa TV leading up to the event.

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