SpaceX's pioneering Polaris Dawn mission will soon begin its audacious journey into Earth's orbit and, with it, its plunge through the radiation belt that envelops our planet.
The four-person civilian crew, led by billionaire businessman Jared Isaacman, will blast off from Agency's International Space Station. Kennedy Space Center in Florida early Tuesday (September 10) after a series of launch delays blamed on Technical problems and bad weatherSoon, the crew will reach a maximum altitude of 870 miles (1,400 kilometers), three times the altitude of the International Space Station (ISS) and farther than any human has flown since Age of Apollo More than 50 years ago.
Over the course of five days, while flying at this record altitude, the SpaceX Dragon Resilience capsule carrying the crew members will pass through the interior Van Allen radiation beltone of two doughnut-shaped bands of highly energetic particles from the Sun that are magnetically trapped around Earth. The belts, which protect our planet and its atmosphere from billions of fast-moving particles, are strongest over the equator and virtually nonexistent over the poles.
Astronauts embarking on longer, more distant missions (to Mars, for example) must safely traverse these belts to reach outer space, so the mission is “a unique opportunity to conduct research in a higher radiation environment,” said Dr. Emmanuel Urquietavice chair of aerospace medicine at the University of Central Florida College of Medicine, told Space.com in a recent interview.
Isaacman and his crewmates, former U.S. Air Force pilot Scott “Kidd” Poteet and SpaceX engineers Sarah Gillis and Anna Menon, will also attempt the First private spacewalk At an altitude of 700 kilometers (435 miles), the crew will be within the safety of the inner radiation belt, which begins about 1,000 kilometers (620 miles) above the surface, during the historic spacewalk.
Unlike previous space missions, which often differed in their research objectives, Polaris Dawn carries a radiation monitoring device similar to the one currently on board the ISS. The device, which is located between 40 scientific experiments on board“This will allow scientists to catalogue radiation levels in a consistent and systematic way,” said Dr. Urquieta. “Radiation characteristics can then be compared.”
SpaceX's crew capsule has undergone rigorous testing to ensure its avionics are not burned up by the intense radiation, which would otherwise deprive crew members of crucial navigation and communication capabilities. While the SpaceX team tested the limits of the avionics components by throwing radiation at them, until they brokeUpcoming dives will test that capability in real time, providing useful data for advancing technologies such as spacesuits and life support instruments that will be needed for longer manned missions in the future.
Scientists also plan to look for biological effects caused by radiation by comparing the health of crew members before and after flight, which would be valuable for designing effective countermeasures and personalizing medicine for astronauts on future missions, Dr. Urquieta said.
Compared with ground-based clinical trials, which typically monitor thousands of participants, about 700 astronauts have flown in space since the 1960s, and the vast majority of them have been men.
The Polaris Dawn crew is comprised of two men and two women, providing a valuable opportunity to assess whether the effects of spaceflight, including radiation, can be attributed to the astronaut's biological sex, Dr. Urquieta said.
“We don't yet have the diverse population that we would like to have on human spaceflight,” he added. Private space missions like Polaris Dawn “are starting to give us information that we wouldn't otherwise have.”