BOULDER — The looming crewed Artemis moon missions, which will send astronauts beyond the protective cocoon of Earth’s magnetic field, are spurring a look at flight rules and sharpening space weather forecasting skills.
Our planet’s atmosphere and magnetic field protect us from the steady stream of radiation and charged particles released by the Sun. But outbursts of the Sun, as recently highlighted by the super-strong geomagnetic storm on May 10 that buffeted Earth via solar flares and coronal mass ejections, can also be a threat to outbound crews heading for the moon.
Given the recent powerful solar eruptions, what impact on Artemis operations would have happened if a crewed mission was now underway?
Ride out the hazard
“Fortunately, most of the spacecraft designed for human exploration — including those for Artemis — are designed to protect our astronauts from most of this radiation hazard,” Ian Cohen, deputy chief scientist for space exploration at the Johns Hopkins Applied Physics Laboratory, told SpaceNews.
“There are also protocols at NASA to monitor and respond to such events and specifically designed areas of the spacecraft where astronauts can shelter to ride out the hazard,” Cohen added.
The largest potential threat is if the astronauts were outside the spacecraft performing an extravehicular activity either in space or on the surface of the moon, Cohen said.
“In that scenario NASA would monitor the event and potentially alter the mission plans — possibly cancelling the [extravehicular activity] — to protect the astronauts. So, while the radiation is a potential hazard for extreme events, NASA does actively monitor the situation and has procedures in place to keep our astronauts safe,” said Cohen.
Forecast, warn, alert
The National Oceanic and Atmospheric Administration’s Space Weather Prediction Center (SWPC) is working with NASA space radiation specialists to bolster space weather support for human expeditions to the moon.
In late 2025, NASA’s Artemis 2 mission is to be the first crewed sojourn to the vicinity of the moon. The 10-day outing will be the first human voyage there since Apollo-era moonwalker flights ended in Dec. 1972.
“We are well prepared for this next Artemis mission, to do the best job of forecasting, warning and alerting the astronauts” when solar events could be a human health issue, said Shawn Dahl, a SWPC service coordinator.
Dahl told SpaceNews that today’s forecasting tool kit features better modeling abilities, higher-quality spacecraft data to gauge particle types and levels churned out by the Sun, along with better computer and communications technology to detect and warn about worrisome events.
Dahl said that those abilities can provide a better idea of when to give an “all-clear” to Artemis astronauts.
Wanted: more fidelity
Space agencies are working hard to provide the best models for solar weather, explained Hazel Bain, science lead for the University of Colorado’s Cooperative Institute for Research in Environmental Sciences at the Space Weather Prediction Center.
“There are a number of solar energetic proton forecast models in the research realm” that are being evaluated by NASA and SWPC, Bain said, with the idea of moving best-of modeling “from the research realm into operations realm.”
“In many ways, what we’re trying to forecast for the new Artemis missions, and looking forward to Mars, is very similar to what we were trying to do for the Apollo era,” said Bain. “Going back to the moon is re-challenging us to understand how well we know this forecasting topic, and how we can improve our forecasts.”
More detailed data is needed, Bain added, about when an event will end and what the peak flux is going to be.
Both SWPC’s Bain and Dahl point to the scheduled June 25 launch of NOAA’s GOES-U. It is the fourth and final satellite in NOAA’s advanced geostationary satellite series and is outfitted with an additional space weather instrument, the Naval Research Laboratory’s Compact Coronagraph. It will image the solar corona and be used to observe Coronal Mass Ejections (CMEs).
Next year, Bain and Dahl continued, NOAA expects to launch its Space Weather Follow On Lagrange 1 (SWFO-L1) spacecraft. Once on duty in its L1 orbit, it will provide a continuous, unobstructed look at the Sun’s corona without interference from the Earth. SWFO-L1 also has a compact coronagraph to spot coronal mass ejections emanating from the Sun.
Crew safety
The ability to better gauge commotions on the Sun is near at hand, so now the Orion mission planners are beginning to work on a crew safety plan for when a dangerous uptick in solar action arises.
Steve Johnson, a research engineer with the Space Radiation Analysis Group (SRAG) at NASA’s Johnson Space Center, provided a look at the four-seater Orion spacecraft and its 10 foot interior diameter during an April Space Weather Workshop held in Boulder, Colorado, organized by the University Corporation for Atmospheric Research and co-sponsored in part by SWPC and the NASA Heliophysics Division.
Flight rules regarding solar events are only at a draft stage, he said, with lots of forward work in process. For radiation monitoring, Orion carries detectors, caution and warning alarms, with crew members outfitted with active dosimeters, said Johnson.
While Orion is relatively highly shielded, Johnson said that in the event of a worrisome solar event, draft Artemis flight rules would have the astronauts establish a shelter utilizing two central stowage bays emptied of contents. Doing so would create a lower dose region within capsule confines. Stowage from the central bays, he said, would be moved to a known “hot spot” within Orion, to help reduce the dose rate around the spacecraft.
Meanwhile, the team is currently sorting out what procedures can be taken by moonwalking crewmembers if an energetic solar proton episode occurs.
A person booting over the lunar terrain has eight hours of life-sustaining consumables, Johnson said, so getting back to the safe haven of a lunar lander within a one to four-hour timeframe is a consideration. But all of this is still forward work, he said, with flight rules intended to be in place for the first Artemis astronauts to strut across the moon, now projected to happen in Sept. 2026.
Engineering solutions, observational and predictive capabilities
Taking part in the space weather meeting was Tonya Ladwig, vice president of human space exploration and Orion program manager for Lockheed Martin Space, builder of the spacecraft.
Ladwig noted that damage to cells and tissue in humans from charged particles can lead to short-term and long-term health impacts. But she stressed the value of engineering solutions plus NOAA and NASA’s space weather observational and predictive capabilities, while spotlighting Orion’s design to protect against high-energy protons, galactic cosmic-rays and secondary particles.
Furthermore, Ladwig noted that Orion’s electronics will also be shielded from solar weather, as the spacecraft features built-in redundancies of its radiation-hardened electronics combined with fault detection and recovery to mitigate risk of mission loss.
Strategies to mitigate risks to both spacecraft and humans must be codeveloped and implemented by government and industry specialists, Ladwig advised.