ESA’s Solar Orbiter will be the first spacecraft to study the sun’s polar zones – Science News

A new sungazing spacecraft has launched on a mission to
chart the sun’s unexplored polar regions and to understand how our star creates
and controls the vast bubble of plasma that envelops the solar system.

At 11:03 pm ET on February 9, the European Space Agency’s Solar
Orbiter rocketed away from Cape Canaveral, Fla. The spacecraft now begins a
nearly two-year convoluted journey — getting two gravity assists from Venus and
one from Earth — to an orbit that will repeatedly take it a bit closer to the
sun than Mercury gets.

Slated to study the sun for at least four years starting in
November 2021, Solar Orbiter is going where few spacecraft have gone. The probe
will soar above and below the orbits of the planets to get a peek at the sun’s
north and south poles — a region no one has yet seen. One of the mission’s many
goals is to see how the poles change when the sun’s magnetic field flips at the
height of the next solar cycle, sometime in
the middle of this decade.  

The probe carries a suite of 10 science instruments,
including cameras and devices to measure the sun’s magnetic field and the solar
wind, a stream of plasma that flows from the sun and eventually peters out at the
solar system’s border with interstellar space (SN: 11/4/19). At Solar
Orbiter’s closest approach to the sun, about 42 million kilometers above the
surface, the sun will appear 13 times as bright as it does from Earth, heating the
spacecraft to nearly 500° Celsius. To view the sun safely, most of its instruments
will peek through protective windows tucked behind sliding doors in the
spacecraft’s heat shield.