CAPE CANAVERAL, Fla. — It’s make or break time for NASA’s new moon rocket.
With 8.8 million pounds of thrust, the rocket — called the Space Launch System (SLS) — is designed to be mightier than NASA’s mighty Saturn V. Its Orion space capsule outsizes its Apollo ancestor by one-third. Yet neither spacecraft has passed the ultimate test: a trip to the moon and back.
That will change Monday (Aug. 29), when NASA aims to launch the SLS megarocket and Orion on Artemis 1, a test flight that serves as the vanguard of the agency’s Artemis program to return astronauts to the moon by 2025. Liftoff is set for 8:33 a.m. EDT (1233 GMT) from Pad 39B here at NASA’s Kennedy Space Center. You can watch the launch live online Monday starting at at 6:30 a.m. EDT (1030 GMT).
“Our zero hour approaches for the Artemis generation,” Mike Sarafin, NASA’s Artemis 1 mission manager, told reporters here Saturday. “We do have a heightened sense of anticipation.”
Related: NASA’s Artemis 1 moon mission: Live updates
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That anticipation is not something NASA owns alone. Up 200,000 spectators are expected (opens in new tab) to flood Florida’s Space Coast here to catch a glimpse of NASA’s first moon rocket to fly in over 50 years. Their hopes mirror NASA’s for a successful mission where success is far from certain.
“This is a very risky mission,” said Jim Free, NASA’s associate director for exploration systems development. “We do have a lot of things that could go wrong during the mission in places where we may come home early, or we may have to have to abort to come home.”
In fact, the mission may not launch at all.
“Our potential outcomes on Monday are that we can go within the window, or we could scrub for any number of reasons,” Sarafin said. “We’re not going to promise that we’re going to get off on Monday.”
NASA has a two-hour window in which to try and launch Artemis 1 on Monday that closes at 10:33 a.m. EDT (1433 GMT). There is a 80% chance of good weather at the start of the window, though that slips to 60% later in the day due to the possibility of rain. NASA has backup launch days on Sept. 2 and Sept. 5, if needed.
On Saturday, NASA detected five lightning strikes at Pad 39B, but none of the strikes affected the SLS rocket itself. They all hit the pad’s lightning protection system, a network of towers and catenary wires, and were not strong enough to pose a concern to the launch, NASA Artemis 1 senior test director Jeff Spaulding said in an update Sunday.
Video: Lightning strikes Artemis 1 launch pad days before liftoff
A long road to the launch pad
NASA has been trying to build a giant new rocket for nearly two decades. In 2004, the agency announced plans for a massive rocket, then called the Ares V, as part of its Constellation program to return to the moon by 2020. That program was ultimately canceled, replaced by what has become the Artemis program, though the Orion spacecraft did survive the transition. The five-segment solid rocket boosters (a bit larger than those used on NASA’s shuttle program), originally part of Constellation’s Ares 1 rocket to launch Orion, also found new life in the SLS.
“We’ve been through our challenges, just like every other piece of this whole rocket,” Bruce Tiller, NASA’s manager for the SLS boosters, told Space.com in an interview. “Everybody’s had their challenges that they’ve overcome over those years. And now I think we’re as ready to go as we can be. And it’s just really exciting.”
Congress directed NASA to build the Space Launch System over a decade ago, calling on the agency to use shuttle-legacy hardware like the solid rocket boosters and RS-25 core engines derived to build a new vehicle for deep space exploration. The first test flight was targeted for 2017 at the time. It is way behind schedule.
“I would say simply that space is hard,” NASA Administrator Bill Nelson, who was in the Senate as a Florida senator when SLS was approved, said…
Read More: ‘Zero hour’ for NASA Artemis 1 moon mission launch on Aug. 29