Skip to main content

How to watch NASA’s first four-engine hot fire of its mighty SLS rocket

NASA Live: Official Stream of NASA TV

NASA is promising a spectacular show of rocket power on Saturday, January 15, and you can watch it live online.

Recommended Videos

The space agency will perform the first four-engine hot fire test of its Space Launch System (SLS) rocket that will launch the first woman and next man to the moon by the end of the decade.

The hot fire will mark the eighth and final part of NASA’s Green Run, a series of demanding tests to ensure the next-generation rocket is ready for space missions. Earlier Green Run tests evaluated, for example, the rocket’s avionics systems, propulsion systems, and hydraulic systems.

Taking place at the agency’s Stennis Space Center near Bay St. Louis, Mississippi, Saturday’s test will focus on the rocket’s core stage, which includes the liquid hydrogen tank and liquid oxygen tank, four RS-25 engines, and the computers, electronics, and avionics that serve as the “brains” of the rocket.

NASA said engineers will “power up all the core stage systems, load more than 700,000 gallons of cryogenic, or super-cold, propellant into the tanks, and fire all four engines at the same time to simulate the stage’s operation during launch, generating 1.6 million pounds of thrust.”

We’ve already witnessed the awesome power of just one of those four engines during an earlier test, so expect something pretty spectacular on Saturday.

If the hot fire goes according to plan, NASA will turn its attention to its highly anticipated crewless Artemis I mission that will see the SLS launch the Orion space capsule on a fly-by of the moon before returning to Earth, a mission currently slated for November 2021. After that, Artemis II will send four astronauts on a fly-by of the moon, with Artemis III following up with a crewed lunar landing — the first since 1972.

How to watch

NASA is currently targeting a two-hour window for the SLS rocket test, starting at 2 p.m. PT on Saturday, January 16. Live coverage of the event will begin at 1:20 p.m. PT on NASA TV, a link to which we’ve embedded at the top of this page. You can also hit this link for the same feed on NASA’s website. Around two hours after the event, the space agency will also broadcast a post-test briefing, so be sure to stick around for that if you want to get all the details on how the test went.

Trevor Mogg
Contributing Editor
Not so many moons ago, Trevor moved from one tea-loving island nation that drives on the left (Britain) to another (Japan)…
How to watch SpaceX’s triple-booster rocket take its 10th flight on Tuesday
The Falcon Heavy rocket on the launchpad at the Kennedy Space Center in Florida.

The Falcon Heavy rocket on the launchpad at the Kennedy Space Center in Florida ahead of its ninth flight in December last year. SpaceX

SpaceX is about to send its powerful Falcon Heavy rocket skyward in its first mission since December last year.

Read more
How to watch NASA’s first spacewalk of 2024
A NASA spacewalk.

NASA Live: Official Stream of NASA TV

UPDATE: The spacewalk was postponed due to a "spacesuit discomfort issue." A new schedule has yet to be announced.

Read more
NASA astronauts sign their moon rocket
NASA astronaut Christina Koch.

Previous

Next

Read more