About Wet Dress Rehearsal:
- It is the final practice run for a high-stakes rocket launch.
- The “wet” in the name refers to the loading of cryogenic fuel (typically liquid oxygen and liquid hydrogen for large rockets) into the rocket’s massive tanks.
- It is a rigorous demonstration of ground team preparedness.
- Wet rehearsals are important because only they can reveal events that happen in cryogenic conditions, e.g., leaks in seals or in the connections between the rocket and ground equipment.
What is a Dry Dress Rehearsal?
- It practices the countdown and important operations without loading cryogenic propellants into the rocket.
- Instead, the team power up vehicle and ground systems, verify its communications equipment, simulate critical events, and validate decision-making and handoffs between launch control, engineering, range safety, and, if applicable, crew operations.
- Many of the testing steps use simulated sensor inputs.
- These rehearsals are useful to reveal logical problems in the flow of events without risking fuel leaks.
Key Facts about Artemis II Mission:
- It is the second scheduled flight of NASA's Artemis program and the first crewed Artemis mission.
- It will be the first mission to carry humans to the moon’s vicinity since 1972.
- It is the first to fly astronauts aboard the Space Launch System (SLS) rocket and Orion spacecraft.
- While Artemis 1 successfully flew Orion around the moon without astronauts in 2022, Artemis 2 will be the first time that humans will travel aboard the spacecraft and venture beyond Low Earth Orbit.
- The astronauts and mission controllers will collect data on Orion and the crew’s performance to assess how ready the Artemis program is to send people to the moon’s surface.
