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Recent airborne science flights to Greenland are improving NASA's understanding of space weather by measuring radiation exposure to air travelers and validating global radiation maps used in flight path planning. This unique data also has value beyond the Earth as a celestial roadmap for using the same instrumentation to monitor radiation levels for travelers entering Mars' atmosphere and for upcoming lunar exploration.
NASA's Space Weather Aviation Radiation (SWXRAD) aircraft flight campaign took place August 25-28 and conducted two five-hour flights in Nuuk, Greenland. Based out of NASA's Langley Research Center in Hampton, Virginia, the mission gathered dosimetry measurements, or the radiation dose level, to air travelers from cosmic radiation. Cosmic radiation is caused by high-energy particles from outer space that originate from our Sun during eruptive events like solar flares and from events farther away, like supernovae in our Milky Way galaxy and beyond.
"With NASA spacecraft and astronauts exploring the Moon, Mars, and beyond, we support critical research to understand - and ultimately predict - the impacts of space weather across the solar system," said Jamie Favors, director of NASA's Space Weather Program at NASA Headquarters in Washington. "Though this project is focused on aviation applications on Earth, NAIRAS could be part of the next generation of tools supporting Artemis missions to the Moon and eventually human missions to Mars."
NASA's Nowcast of Aerospace Ionizing Radiation System, or NAIRAS, is the modeling system being enhanced by the SWXRAD airborne science flights. The model features real-time global maps of the hazardous radiation in the atmosphere and creates exposure predictions for aircraft and spacecraft.
"The radiation exposure is maximum at the poles and minimum at the equator because of the effect of Earth's magnetic field. In the polar regions, the magnetic field lines are directed into or out of the Earth, so there's no deflection or shielding by the fields of the radiation environment that you see everywhere else." explained Chris Mertens, principal investigator of SWXRAD at NASA Langley. "Greenland is a region where the shielding of cosmic radiation by Earth's magnetic field is zero."
That means flight crews and travelers on polar flights from the U.S. to Asia or from the U.S. to Europe are exposed to higher levels of radiation.
The data gathered in Greenland will be compared to the NAIRAS modeling, which bases its computation on sources around the globe that include neutron monitors and instruments that measure solar wind parameters and the magnetic field along with spaceborne data from instruments like the NOAA GOES series of satellites.
"If the new data doesn't agree, we have to go back and look at why that is," said Mertens. "In the radiation environment, one of the biggest uncertainties is the effect of Earth's magnetic field. So, this mission eliminates that variable in the model and enables us to concentrate on other areas, like characterizing the particles that are coming in from space into the atmosphere, and then the transport and interactions with the atmosphere."
The SWXRAD science team flew aboard NASA's B200 King Air with five researchers and crew members. In the coming months, the team will focus on measurement data quality checks, quantitative modeling comparisons, and a validation study between current NAIRAS data and the new aircraft dosimeter measurements.
All of this information is endeavoring to protect pilots and passengers on Earth from the health risks associated with radiation exposure while using NASA's existing science capabilities to safely bring astronauts to the Moon and Mars.
"Once you get to Mars and even the transit out to Mars, there would be times where we don't have any data sets to really understand what the environment is out there," said Favors. "So we're starting to think about not only how do we get ready for those humans on Mars, but also what data do we need to bring with them? So we're feeding this data into models exactly like NAIRAS. This model is thinking about Mars in the same way it's thinking about Earth."
The SWXRAD flight mission is funded through NASA's Science Mission Directorate Heliophysics Division. NASA's Space Weather Program Office is hosted at NASA Langley and facilitates researchers in the creation of new tools to predict space weather and to understand space weather effects on Earth's infrastructure, technology, and society.
