A trio of astronauts will depart the International Space Station this evening, embarking on a three-and-a-half hour journey back to Earth. The exiting crew includes Russian cosmonaut Anatoly Ivanishin, Takuya Onishi of the Japan Aerospace Exploration Agency, and NASA astronaut Kate Rubins, all of whom are wrapping up a nearly four-month stay aboard the ISS. During their time on the station, the three have helped perform hundreds of science experiments, and Rubins became the first person to sequence DNA in microgravity.

Things get underway at 4:45PM ET

Things get underway at 4:45PM ET, when the astronauts say farewell to the other three crew members who will be staying on the station. The three then board the Soyuz capsule that will take them home and close the hatch. The Soyuz is scheduled to undock from the ISS at 8:37PM ET and stay in orbit for the next two and a half hours. Then around 11:06PM ET, the vehicle will ignite its engines, taking itself out of orbit and putting it on a descent to Earth.

After that, it’s about an hour before the Soyuz reaches the ground. Two of the three modules on the Soyuz are jettisoned before the vehicle enters the atmosphere, leaving just the Descent Module that holds the crew. As that module falls, it reaches a whopping speed of 514 miles per hour, until a series of four parachutes are deployed to slow the module down for landing. And just a second before touchdown, six engines on the module ignite to slow the vehicle even more, so that the astronauts experience as comfortable a landing as possible. That touchdown is supposed to happen tonight around 11:59PM ET.

NASA TV will provide coverage of the entire trip tonight, including closure of the Soyuz hatch, undocking, and landing. Check back this afternoon to follow the astronauts’ journey back home.