In 2009, using NASA’s Interstellar Frontier Explorer, also known as IBEX, astronomers have spotted a strange ribbon-like structure dancing between our solar system and the rest of interstellar space.
The discovery of the IBEX ribbon, which is invisible to both telescopes and the human eye, was one of scientists’ first forays into understanding our heliosphere, a bubble-shaped shield made of solar winds.
“Most instruments that detect particles in space detect charged particles,” explains Daniel Reisenfeld, principal investigator at the Los Alamos National Laboratory in New Mexico and principal author of the study. But IBEX is unique.
It detects energetic neutral atoms, or ENA, ions that originate from the sun but collide with interstellar electrons, neutralizing them. These atoms can be found anywhere in space, and observing ENA fluxes over time can be a powerful imaging tool.
So what exactly was this mysterious ribbon? Scientists have since determined that what they were seeing was a giant swath of ENA lighting up the night sky.
Using data collected by IBEX on ENA as it only mapped a single 11-year solar cycle, the time between changes in the sun’s magnetic field, the researchers constructed a three-dimensional map of the whole. of the heliosphere, which Reisenfeld says protects the Earth and other planets from harmful radiation. .
“Our Earth is bombarded with cosmic rays, galactic cosmic rays all the time,” he says. These rays can subtly affect planes flying near the poles, often when traveling between Europe or Asia and the United States.
Scientists say that in order to study the astrospheres of other planets, which is what heliospheres are called when they surround other stars, we must first understand our own.
“Many of the physical models under development are based on the findings of the IBEX mission,” explains Nikolai Pogorelov, professor of space science at the University of Alabama at Huntsville. “It’s not just experimental,” he said, adding that it “will be used for [a] real goal.