Artemis I: Here are the biggest upcoming milestones for NASA's historic mission

After numerous delays, NASA's Artemis I mission finally took to the skies yesterday.

The moon-bound mission lifted off at 1:47 am EST (0647 GMT), on Nov.16, from Pad 39B at NASA's Kennedy Space Center.

It is the first of NASA's Artemis missions, which will eventually send humans to the moon for the first time since Apollo 17 in 1972. It also marks the first-ever flight of the Space Launch System (SLS), NASA's most powerful rocket.

Here's what's next for NASA's 25-day uncrewed test mission to the moon and back.

A step-by-step guide to Artemis I

Almost an hour and a half after Artemis I launched yesterday, the SLS's interim cryogenic propulsion stage (ICPS) carried out an 18-minute engine burn, boosting the Orion capsule, which had separated from atop the SLS's upper stage, to a speed of 22,500 mph (36,210 kph).

Once this burn was complete, Orion had completed its trans-lunar injection, meaning it's now on the outbound coasting phase, flying through open space toward the moon.

The European Space Agency-built Orion capsule will now spend the next six days flying to the moon, performing a number of trajectory correction maneuvers along the way.

On Monday, November 21, Orion will arrive at the moon and perform its closest pass of our nearest neighbor, flying within about 60 miles (100 kilometers) of the lunar surface. It will do so to perform a gravity slingshot, sending the spacecraft far beyond the moon.

10 days after launch, on Nov.25, the spacecraft will perform another engine burn to insert itself into a distant retrograde orbit (DRO) around the moon. It will spend roughly a week in this orbit at an altitude of approximately 38,000 miles (61,000 km) above the lunar surface.

If all goes to plan, on Nov.28, 13 days into the mission, Orion will break the record for the farthest-ever distance traveled by a spacecraft built for humans by traveling almost 300,000 miles (483,000 km) from Earth. It will beat the previous record set by NASA's Apollo 13 mission.

During the DRO phase of the mission, sensors aboard Orion will take measurements to help better understand the conditions astronauts will face during the Artemis II mission — Artemis II will carry out the same journey with a crew aboard in 2024, while Artemis III will land the first woman and first person of color on the moon, either in 2025 or 2026.

Putting the ESA's Orion spacecraft to the test

The Orion spacecraft will carry three manikin's aboard with radiation sensors and sensors for gravimetric and vibrational forces during the lunar missions. These manikins will also test a novel radiation vest technology called AstroRad. Two of the manikins, Helga and Zohar, were designed to mimic human bone and tissue. Specific parts were built to mimic ovaries and breast tissue, as these are more susceptible to radiation.

Shortly after yesterday's launch, NASA Administrator Bill Nelson explained in a media briefing that "this is just the test flight. We are stressing [SLS and Orion] and testing [them] in ways that we will not do to a rocket for humans." He added that the space agency is working hard to "make it as safe as possible when astronauts crawl onboard and go back to the moon."

Wave, everybody 👋 Here's the first view of Earth from a human-rated spacecraft, not seen since 1972 🤯#Artemis pic.twitter.com/AgQ7uje2Me

— Human Spaceflight (@esaspaceflight) November 16, 2022

On Dec.1, 16 days into the mission, the Orion spacecraft will perform its DRO departure burn. This will lower the craft to its second-lowest lunar pass, after which it will perform a final burn to send it on its way back to Earth. That journey will, once again, last six days, resulting in a splashdown over the Pacific Ocean on December 11.

Orion will travel at around 25,000 mph (40,000 km/h) while reentering Earth's atmosphere, testing the spacecraft's heat shield by reaching temperatures up to 5,000 degrees Fahrenheit (2,750 degrees Celsius). Parachutes will slow the capsule down before it splashes into the ocean.

This will draw a close to the very first mission of NASA's ambitious Artemis program, which aims to send humans back to the moon and establish a permanent lunar presence that will serve as a stepping stone for further human exploration of the cosmos.