Tensions between the U.S. and the Soviet Union reach an all-time high on the moon, throwing multiple missions into jeopardy.

Ed handles a trespasser. Ellen and Deke chart a new course without Mission Control.

Tensions on Earth and Mars come to a head.

A crisis in space puts the Apollo 24 and 25 crews in peril.

The Martian crew debates how to save the life of one of their own.

The rivalry between American astronauts and Soviet cosmonauts intensifies as last-minute changes impact the Pathfinder mission plan.

A surprise maneuver during the journey to Mars provokes desperate measures.

Ed and the crew change Apollo 15's landing site after lunar ice is detected.

Nearly 10 years have passed. Danielle and Ed attend a celebration, where things take a terrifying turn.

NASA preps a Jamestown relief mission, while Karen waits for news at the hospital.

A commercial spaceflight company makes an announcement. The choice over who'll command the Mars mission leads to a shift in personnel.

Ed, Gordo, and Danielle struggle with an extended Jamestown mission.

The race to land first on Mars brings together unexpected allies.

Things start to go awry just as an important mission approaches a critical juncture.

Deke must recruit female astronauts after Russia lands a woman on the moon.

A dispute on the moon prompts NASA officials to consider arming astronauts. Ed’s past comes back to haunt him.

Plans to leave Mars are complicated by an unforeseen issue.

Nearly a decade later, technology and lunar exploration have taken huge strides—but a solar storm threatens the astronauts on Jamestown.

As NASA scrambles to prepare for the launch to Mars, Margo is confronted with a harsh personal reality.

Unlikely partnerships are formed at a high-stakes international conference.

A group on Mars takes drastic measures. Margo grapples with a new assignment.

A training accident spurs a national debate about women astronauts.

Gordo returns to space. Molly faces an upsetting new reality. Aleida confronts her first major hurdle at work.

After a sudden crisis, the Martian crews pull together.

A launchpad accident leads to delayed missions and FBI background checks.