Carefully constructed, technologically advanced balloons soar in the Antarctic sky, transmitting space weather updates to a team of scientists. For the past month, physics and astronomy professor Robyn Millan has lived on the southernmost continent, using instrument-laden balloons to gather data on radiation belts that impact space activity around the Earth.
The mission, Balloon Array for Radiation Belt Relativistic Electron Losses, complements data collection by NASA satellites and aims to research natural processes in space that impact satellites and GPS technology.
Researchers launch eight-story tall balloons to measure X-rays produced by electrons in the earth’s atmosphere. The group has launched nine balloons since Dec. 27 and plans to release 11 more by the end of the mission.
The researchers keep between five and eight balloons afloat simultaneously, each equipped with instrumentation used to collect data on the Van Allen radiation belts. The belts are zones of particles that influence disturbances in Earth’s magnetic sphere caused by the sun.
Millan, principal investigator and leader of the 30-person campaign, said the research serves both intellectual and practical purposes.
The data collected by the balloons is combined with that of NASA’s Van Allen probes, two spacecraft dedicated to observing the radiation belts, and analyzed to inform scientists’ understanding.
Comprehending space weather will allow researchers to improve forecasting and prevent damage to technology.
“It’s just like any other weather,” Halford said. “If you can predict it, you can work around it.”
The radiation belts are composed of charged electrons and can damage orbiting satellites. Sudden bursts of activity can cause interruptions to everyday tools such as those used by aircraft, Millan said.
Because people so deeply rely on satellite technology, the ability to predict space weather is crucial. Space weather fluctuations can distort GPS data, Dartmouth researcher Alexa Halford said.
“Only being able to know where you are within a meter is generally not a problem for people,” she said. “But if you’re a farmer and fertilizing a swath of land that is 10 centimeters long and you want to be able to go back in the spring and plant seeds in the spot you just fertilized in the fall, being off by a meter is not very useful.”
The conditions in Antarctica have presented some challenges for the researchers, as high winds occasionally prevent the team from launching the fragile balloons, Halford said.
The balloons must remain within a narrow region of the atmosphere — approximately 22 to 38 kilometers above the Earth’s surface — to collect useful data, Millan said. Two balloons are being terminated this week because of their low altitude.
“Of course there are some risks,” Millan said. “The plastic of the balloon is thin. Sometimes we find the balloons we send up and we try to re-use them. Other times we can’t.”
Poor phone reception can interfere with daily telecommunications, Dartmouth-stationed research assistant Leslie Woodger said. As a result, team members in Hanover sometimes find it difficult to communicate with those in Antarctica.
While most of Millan’s team will remain in Antarctica until Feb. 20, researches in Hanover are currently making models using the collected data to see how theories compare to reality.
The team continues to make improvements like reducing the number of solar panels attached to the balloons to save space and weight, Woodger said.
Currently based out of the South African Antarctic Station and Halley Bay station in Antarctica, the campaign includes contributions from other institutions, such as the University of California at Berkeley, the University of California at Santa Cruz and the University of Washington, among others. Millan received roughly $9.3 million in NASA funding for the project.
While the researchers are currently focused on collecting data, they hope to be able to publish results by the end of the year, Millan said.
