Surrounding our solar system is a natural and enigmatic cosmic shield called the heliosphere — and a new mission has launched to help astronomers better understand it.

Created by the solar wind, a constant flow of charged particles that stream away from the sun, the heliosphere acts as an enormous bubble that protects the planets in our solar system from cosmic radiation permeating the Milky Way, our home galaxy.

In addition to Earth’s protective magnetic field, the heliosphere plays a major role in why life is possible on our planet — and how it perhaps once existed on others such as Mars.

Over half a dozen missions have contributed to how astronomers understand the heliosphere, and two enduring spacecraft, the Voyager probes, have collected key data after exiting the heliosphere to explore interstellar space.

But the new IMAP, or Interstellar Mapping and Acceleration Probe, mission is designed to investigate how the sun forms its solar wind, and how that solar wind interacts with interstellar space at the boundary of the heliosphere, which begins at a range three times the distance between Earth and Pluto, according to NASA.

This image shows NASA’s IMAP mission being loaded into the thermal vacuum chamber of NASA Marshall Space Flight Center’s X-Ray and Cryogenic Facility in Huntsville, Alabama, in March.
This image shows NASA’s IMAP mission being loaded into the thermal vacuum chamber of NASA Marshall Space Flight Center’s X-Ray and Cryogenic Facility in Huntsville, Alabama, in March.
Ed Whitman/NASA/Johns Hopkins APL/Princeton

The spacecraft’s 10 instruments will also fill gaps in the existing map of the heliosphere, pieced together from data collected by previous missions, and help further explain how the heliosphere largely shields our solar system from damaging cosmic rays, the most highly energetic particles in the universe.

Along with two other space weather missions that lifted off aboard the same rocket on Wednesday, IMAP will help scientists better predict when solar storms unleashed by the sun could affect our planet. When aimed at Earth, harsh radiation from the storms, also known as space weather, can pose risks to astronauts on the International Space Station as well as interfere with communications, the electric power grid, navigation, and radio and satellite operations.

“This next set of missions is the ultimate cosmic carpool,” said Dr. Joe Westlake, director of NASA’s Heliophysics Division, during a news conference on Sunday. “They will provide unprecedented insight into space weather. Every human on Earth, as well as nearly every system involved in space exploration and human needs, is affected by space weather.”

A conceptual animation showing the heliosphere.
NASA Goddard Space Flight Center Conceptual Image Lab

Mapping the heliosphere

The heliosphere was first theorized by multiple scientists investigating the concept of cosmic rays and the solar wind in the late 1950s, according to NASA. They believed the sun provided a web of magnetic fields and solar wind that created a boundary surrounding Earth and the rest of the solar system.