Back in February, the European Space Agency (ESA) and NASA launched the Solar Orbiter, a spacecraft developed by the two agencies in a new way of studying the sun. The probe is now approaching our star for the first time since the successful launch, and mission control is preparing to test the onboard instrument by collecting close-up images of the sun and its surroundings.
NASA’s Parker solar probe, launched in 2018, is closer to the sun than the solar orbiter, but its mission is completely different. It will travel through the sun’s atmosphere to study the origin of high-energy solar particles and how the solar wind accelerates, while solar orbiters will explore the mysteries of our stars and their polar regions by gaining unprecedented perspective.
It will do so through an unusual path, using Venus’s gravity to gradually improve its orbit and observe the sun from an ever-higher latitude orbit. Eventually, this will lift it into orbit, allowing it to study the sun’s poles and move to latitudes up to 34 degrees.
Such a feat is not expected to take place until a decade later, but Monday marks the first real milestone in the Solar Orbiter’s journey. The project’s mission control unit confirmed that on June 15, the probe approached the sun for the first time, 77 million kilometers (48 million miles) from the sun’s surface, about half the distance from the sun.
After the first overflight, the team is now preparing to test 10 instruments on the solar orbiter, including energy particle detectors, magnetometers, solar wind plasma analyzers, X-ray spectrometers/telescopes, spectroscopic imaging devices and solar-layer imagers. The tools are designed to study how the sun creates the solar wind to create the heliospheric layer, and next week will give the team a chance to test them.
“We’ve never taken pictures of the sun from a closer distance than this,” said Daniel M?ller, a project scientist for ESA’s Solar Orbiter. “There have been higher-resolution close-ups, such as the four-meter Daniel Wells Solar Telescope (DKIST) in Hawaii earlier this year. But from Earth, because of the atmosphere between the telescope and the sun, you can only see a small portion of the solar spectrum you see from space. “
Similarly, the Parker Solar Probe does not carry a telescope capable of imaging the sun directly, so the images collected by the Solar Orbiter team over the next week or so should provide a fascinating and unique perspective. “This will be the first time we’ll be able to put together images of all the telescopes to see how they capture complementary data on various parts of the sun, including the sun’s surface, the outer atmosphere or the corona, and the wider heliospheric layer around the sun,” Daniel said. “
Given the distance from the spacecraft, it is expected that the images will take about a week to return to Earth. The team will then work on the images, which they hope to release to the public by mid-July. Meanwhile, Daniel will continue his mission during this cruise until November 2021. It will then begin its main scientific phase, which will bring it closer to 42 million kilometers (26 million miles) from the sun.