TheArtemis II missionis now far closer to the moon than it is to Earth, with four astronauts cruising toward their target on a slingshot trip that will reach deeper into space than any human has traveled before.
The journey — crewed by NASA's Reid Wiseman, Victor Glover and Christina Koch and Canadian Space Agency astronaut Jeremy Hansen — marks the first time humans have left Earth orbit since 1972 with the Apollo 17 mission. And with Glover, Koch and Hansen aboard, the it also represents the first time a Black astronaut, a woman astronaut and a non-American astronaut, respectively, have ventured this far.
"Humanity has once again shown what we are capable of, and it's your hopes for the future that carry us now on this journey around the moon," Hansen said Thursday.
Orion is now on what's called a "free return trajectory." That's spaceflight parlance for a slingshot trip: Because of orbital dynamics and the moon's gravity, even if Orion never fires its engine again, the capsule will still swing around the moon and head back to Earth.
The mission, which took off at 6:35 p.m. ET Wednesday, marks the inaugural crewed flight of NASA's Artemis program — a long-term plan to return humans to the moon and eventually establish a lunar settlement. After lifting off atop a towering Space Launch System rocket, the astronauts immediately began putting Orion through its paces, including taking their Orion spacecraft for a 70-minute manual test-drive called a "proximity operations demonstration."
For several more days, the crew members will live, eat, sleep, work out and carry out science experiments inside the campervan-size space of Orion. All the while, they'll face a multitude of risks that are inherent to a deep-space mission.
Here's what has happened so far, what's ahead and what you'll want to watch for as Artemis II makes its way around the moon.
Live views of the crew
While the astronauts keep some of their time tucked inside the 16.5-foot-wide (5-meter-wide ) Orion capsule private, NASA has been broadcasting activities inside the capsule nearly every day of the mission.
NASA has also been giving space enthusiasts the opportunity to tune in and listen to public affairs events during which the astronauts speak to journalists and others on the ground. The first such event happened on Thursday, with reporters prompting the crew to share some fascinating details and reflections.
Wiseman, the mission's commander, detailed a moment aboard Orion that had left the crew speechless.
On Thursday evening, "Mission Control Houston reoriented our spacecraft as the sun was setting behind the Earth," Wiseman said, "and I don't know what we all expected to see at that moment — but you could see the entire globe, from pole to pole.
"You could see Africa, Europe, and if you looked really close, you could see the northern lights. It was the most spectacular moment, and it paused all four of us in our tracks."
The times and dates of upcoming public affairs events are postedhere.
A pivotal burn
The Orion spacecraft crossed one of its most anticipated milestones on Thursday, Flight Day 2, to set the rest of the mission on track for a lunar flyby: the translunar injection burn.
The translunar injection burn is critical for increasing Orion's velocity, allowing the spacecraft to leave behind a circular orbit of Earth and transfer to an oval-shaped orbit that could help it reach the moon.
During the burn, Orion's service module, which provides the spacecraft with power, propulsion and thermal control, gave the capsule a big push to embark on a four-day trip around the moon before completing a figure eight to return to Earth.
The burn lasted for five minutes and 50 seconds, with Orion being just 115 miles above Earth, according to NASA.
A key comms test
Among the activities planned for Day 3 was a successful test of communications equipment via the Deep Space Network, a communications system that supports space missions and provides radar and radio observations.
The DSN is "a ground-based network of large tracking dishes all around the world that together can determine Orion's location while it is in deep space outside the range of GPS," according toNASA.
The network consists of antennas positioned equidistant from one another in the United States, Spain and Australia, according to NASA.
These aren't your typical TV satellites that give you the latest cable channels. Each DSN antenna is about 230 feet (70 meters) wide — taking up about two-thirds of a football field. DSN satellites also have a tracking capacity, providing measurement to the ground crew to allow them to determine a spacecraft's precise location and velocity.
However, there will still be moments during the remainder of the mission where the Artemis II astronauts will lose all contact with the team of mission controllers as they attempt to go farther than any human has ever gone before.
Advertisement
One of those blackouts will occur during the roughly 40-minute period during which the crew is traveling closest to the moon's surface as they venture to the lunar far side, blocking data from transmitting to or from Earth.
Entering the 'sphere of influence'
En route to the moon, the Orion spacecraft will use its engine to stay on course, carrying out what NASA calls "trajectory correction" maneuvers. It's all in the name of keeping the vehicle on a precision course toward that silvery orb in the sky.
At one point on Day 5 of this flight, late this Sunday, the spacecraft will officially cross the threshold of the lunar sphere of influence — the point in space where the tug of the moon's gravity is stronger than Earth's gravity.
A record-breaking lunar flyby
Day 6 of this mission will bring the highly anticipated crowning achievement. A sweeping lunar flyby will offer the crew unprecedented views of the moon's far side — and allow the team to surpass the record for the farthest humans have ever traveled in space.
If all goes as planned, Artemis II will best the record set by Apollo 13 in 1970 by 3,366 miles (about 5,400 kilometers), reaching 252,021 miles (about 405,000 kilometers) from Earth.
During the closest approach to the heavily cratered lunar surface, the astronauts will capture images and describe what they see to teams in mission control on Earth. The crew will rely on lessons learned from training in the geologic wonderlands and lunar-like environments of places such as Iceland to note details about the shapes, textures and colors of impact craters and ancient lava flows on the moon.
The features the astronauts observe could help inform the landing sites for future Artemis missions and reveal more about the moon's mysterious past.
Chatting with the ISS
The Artemis II crew is expected to make a special call to other humans currently in space: the seven astronauts aboard the International Space Station. NASA officials confirmed Thursday the ship-to-ship call is planned to occur on the seventh day of the mission.
Ahead of the launch of the Crew-12 mission to the ISS, NASA astronaut Jessica Meir shared in January that part of the Artemis II flight plan is a scheduled call between the Orion spacecraft and the space station.
She's excited to talk to Koch, with whom Meir embarked on the first all-female spacewalk in 2019, as well her astronaut classmate Victor Glover and "astronaut uncles," Reid Weisman and Canadian Space Agency astronaut Jeremy Hansen.
Meir said she and her crewmembers aboard the space station look forward to tracking the journey of their friends and colleagues around the moon.
"We're all very excited to be in space at the same time," Meir said.
A flaming-hot reentry
After more than a week of breaking records and completing test objectives, the crew will have one crucial checklist item left to cross off: coming home.
It's no easy task.
The final phase of flight, called "reentry," happens when the Orion capsule plunges into the thick inner band of Earth's atmosphere while still traveling more than 30 times the speed of sound. The process causes a violent compression of air molecules that can heat the spacecraft's exterior to more than 5,000 degrees Fahrenheit (2,760 degrees Celsius).
It's always one of the riskiest parts of any mission, but for Artemis II the stakes are particularly high.
There's a known issue with a part of theOrion capsule's heat shield, which is a part affixed to the spacecraft's circular bottom that's made of an ablative material — meaning it's meant to char and erode as it's exposed to heat. NASA officials has acknowledged that the heat shield on this vehicle is imperfect — a fact they discovered during a 2022 uncrewed test flight called Artemis I. The Orion capsule returned from that mission with a heat shield that was pockmarked with divots and cracks, which is not how the heat shield is supposed to behave. (Heat shields for future Orion capsules have been manufactured differently.)
But mission managers opted to address the issue this time around by reconfiguring the Orion's reentry path, choosing not to complete a "skip" maneuver, in which the capsule dips into the atmosphere, pulls back out, and dives in again. The skip approach used during Artemis I was intended to allow Orion to target a precise splashdown site.
In order to create a more favorable heating environment for the suboptimal heat shield, Artemis II's Orion spacecraft will make a more subtle loft-type maneuver.
Gathering data about how the heat shield behaves this time around is actually a key mission goal.
Jacopo Prisco contributed to this story.
NASA's Artemis program is sending humans into deep space for the first time in more than five decades. Sign up forCountdown newsletterand get updates from CNN Science on out-of-this-world expeditions as they unfold.
For more CNN news and newsletters create an account atCNN.com
