Artemis launch live: Watch the NASA rocket launch livestream

One of the most momentous tests in NASA history is set to launch in the wee hours (ET) of Wednesday, Nov. 16.

It's the first, much-anticipated demonstration of the agency's new 322-foot-tall moon rocket, the Space Launch System (SLS). The launch, originally slated for late August, has now been delayed multiple times by the likes of an engine problem, leaking fuel, and violent storms. These flight hiccups, however, aren't surprising: This is a test of a giant, complex rocket that will one day be responsible for carrying astronauts into space. It takes time to get it right.

If successful, the critical mission, called Artemis l, will pave the way for NASA astronauts to return to the moon, as early as 2025. Ultimately, the space agency plans to use this colossal rocket to establish a permanent U.S. presence on and around the moon.

After a 50-year lunar absence, SLS — though hugely expensive, delayed, and tangled in U.S. politics — will enable NASA to restart its human exploration of deep space.

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Rain or high winds can often cause launch delays or scrubs. As of Nov. 14, NASA said the weather looks 90 percent favorable for the SLS rocket to launch on Nov. 16. Those are good odds.

What time does Artemis-I launch?

How to watch: NASA will livestream the launch on NASA TV, which you can watch on NASA's website, on NASA TV's YouTube Channel, or on NASA's livestream found just below.

When to watch: The space agency plans to launch the SLS rocket as early as 1:04 a.m. ET on Wednesday, Nov. 16. NASA has a two-hour time window to blast the rocket into space. The agency's live launch coverage starts on Tuesday, Nov. 15 ET at 10:30 p.m. ET, though they will start fueling the rocket earlier in the day.

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A launch at such early hours might seem strange — but there's good reason for it. There are specific windows of time for a launch that will allow the Orion spacecraft (which will eventually carry astronauts) to meet its lunar target, receive ample sunlight for power, and safely splash down in the ocean during daylight hours.

What the Artemis l mission will do

1. The uncrewed mission will prove that the SLS rocket can lift the Orion spacecraft into space and help propel it to the moon. If successful, the rocket will become the most powerful launch vehicle in the world.

2. NASA spaceflight engineers will scrutinize the performance of Orion as it travels through space, loops around the moon a number of times, and then returns to Earth. The mission will last weeks.

3. Orion will plummet through Earth's atmosphere and parachute down into the Pacific Ocean. This all has to go smoothly and safely: Astronauts will be on the next mission, Artemis II, which will launch as early as late 2024.

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