October 16, 2012
New Tool Allows For Real-Time Space Radiation Forecasts
Lee Rannals for redOrbit.com - Your Universe Online
Astrophysicists have created the first online system for predicting and forecasting the radiation environment in near-Earth, lunar, and Martian space environments.
"If we send human beings back to the moon, and especially if we're able to go to Mars, it will be critical to have a system like this in place to protect astronauts from radiation hazards," said associate professor of physics Nathan Schwadron.
Schwadron is the lead developer of a new tool known as PREDICCS, which is able to integrate numerical models of space radiation. The tool was made possible through NASA's Living With A Star (LWS) Targeted Research and Technology program.
Schwadron's website provides updates of the radiation environment on an hourly basis and archives the data weekly, monthly, and yearly.
The record provides a clear picture of when a safe radiation dose limit is reached for skin or blood-forming organs.
"What we really need to know is how hazardous this cycle of radiation is," Schwadron said. "How often do we see large events that have significant risk associated with them? Those questions can only be answered if you're continually building up the database of events and the risk associated with them."
He said the space community sees radiation hazards as a "showstopper," and there has never really been a tool to challenge that view until now.
"There hasn't been enough work done to ask, 'Is it really a showstopper and, if so, why, and what are the problems we need to solve so that it isn't a showstopper," Schwadron said.
PREDICCS uses the solar energetic particle data from the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) instrument on NASA's Lunar Reconnaissance Orbiter as a measurement.
CRaTER has made the most accurate and comprehensive measurements of radiation at the moon than any other instrument.
Recent solar events measured by CRaTER showed billions of tons of high-energy particles ripping through space, and those measurements were matched nearly perfectly by PREDICCS, according to the astrophysicists.
"For the whopping solar events of January 23 and March 27 of this year, our predictions seem to be within 20 to 30 percent of what was observed, which is incredible. These types of highly accurate comparisons have never been made before," Schwadron said.
CRaTER has not only provided the validation that PREDICCS models are accurate, but has done so in the context of how the radiation data would impact human beings on the moon or on a mission to Mars.
"We needed to accurately assess what the biological impacts are to make the best quantitative comparisons between models and observations," says Schwadron, "and having a system like this in place now is sort of like flying a trial balloon in preparation for a return to the moon and a trip to Mars."
PREDICCS uses two radiation environment models to make radiation assessments, including the Earth-Moon-Mars Radiation Environment Module (EMMREM).
"Complex applications like EMMREM are able to leverage observations from all relevant space missions," said NASA's Madhulika Guhathakurta, LWS program scientist.
Schwadron said for the first time, people are able to see the effects of space radiation playing out in near real-time, opening up a new window "to an otherwise invisible world."