The sun readies for its close-up as Europe's Solar Orbiter approaches
No spacecraft before has taken a camera so close to the sun.
The European Solar Orbiter mission will make its closest approach to the sun later this month, promising to capture images that could unravel some of the mysterious behaviours of the star at the heart of our solar system.
Solar Orbiter, a European Space Agency (ESA) mission with a contribution from NASA, launched in February 2020. It caused a stir already during its first close approach to the sun in June 2020
when the spacecraft's imagers captured never before seen phenomena on the sun's surface, the miniature solar flares nicknamed the campfires.
When those images were taken, Solar Orbiter was about half-way between Earth and the sun, at a distance of about 48 million miles (77 million kilometers). The upcoming approach will be even closer.
Solar Orbiter will photograph the sun from a distance of about 30 million miles (48 million kilometers). No spacecraft before has taken a camera so close to the sun, which means that Solar Orbiter will break its own 2020 record.
Scientists want to know whether the campfires (each between 250 to 2,500 miles wide) release their energy into the surrounding space, as it could explain why the sun's outer atmosphere, the corona, is so hot.
Scientists want to know :
At more than 1.7 million degrees F (1 million degrees C), the corona is much hotter than the solar surface, which has a temperature of about 9,900 degrees F (5,500 degrees C). The difference defies logic, as material farther away from the source of heat should be colder, not hotter.
The closest approach will take place on March 26, but Solar Orbiter will spend three weeks overall closer to the sun than the orbit of Mercury, the innermost planet of the solar system,
Another solar observing spacecraft by NASA, the Parker Solar Probe, is also making periodic dips to an extreme close distance to the sun. On Feb. 25, the heavily shielded spacecraft got within 5.3 million miles (8.5 million kilometers) of the solar surface, which is 14 times closer than Mercury's orbit.