NASA has announced it is planning to launch a mission in 2024 that will study how incoming particles from interstellar space interact with our Sun’s protective bubble.
The $500-million mission is called the Interstellar Mapping and Acceleration Probe (IMAP), and it will be placed 1.5 million kilometers (1 million miles) from Earth in a region known as Lagrange point 1 (L1). This is an area of gravitational stability where the Sun and Earth’s gravity sort of cancel out.
Positioned here, the spacecraft will be tasked with studying the heliosphere. This is a bubble of charged particles and magnetic fields created by the Sun, which extends far out into the Solar System.
At the point where the heliosphere meets interstellar space, known as the heliopause and the bow shock, the charged particles collide with incoming cosmic radiation. Not all are stopped, however, and some make their way into the Solar System – which will be studied by IMAP.
“This boundary is where our Sun does a great deal to protect us,” Dennis Andrucyk, deputy associate administrator for NASA’s Science Mission Directorate in Washington, said in a statement. “IMAP is critical to broadening our understanding of how this ‘cosmic filter’ works.”
On board the spacecraft will be 10 scientific instruments to probe these incoming particles. These will include cosmic rays, streams of particles that can have implications for the health of humans and spacecraft.
“The implications of this research could reach well beyond the consideration of Earthly impacts as we look to send humans into deep space,” Andrucyk added.
While IMAP will be staying relatively near Earth, we have actually sent several spacecraft out through the heliosphere before. The Voyager 1 and 2 probes, launched in 1977, have both crossed the boundary into the heliopause, with the former having now reached interstellar space.
Voyager 1 has given us our first readings showing the Sun’s influence out into interstellar space, which is pretty cool. Data from the spacecraft has shown us that the direction of the magnetic field changes at the boundary with interstellar space, possibly as a result of the solar wind. It is not expected to be truly out of the solar wind’s influence until 2025.
IMAP will hopefully tell us more about what’s getting through this barrier, though, and give us a clearer picture of what our Sun’s bubble really looks like.