The closest images ever taken of the Sun, captured at a distance of about 48 million miles from the solar surface, were released during a livestreamed news conference by NASA and the European Space Agency (ESA) on Thursday morning.
The unprecedented close-ups show our star from the perspective of Solar Orbiter, a spacecraft launched in February, that pointed 10 of its instruments at the Sun around its closest approach (so far) in mid-June.
“We’ve never been closer to the Sun with a camera and this is just the beginning of the long, epic journey of Solar Orbiter, which will take us even closer to the Sun in less than two years’ time,” said Daniel Müller, Solar Orbiter Project Scientist at ESA, in the briefing.
The spacecraft took these shots at a point that is roughly halfway between the Sun and Earth, offering an unprecedented look at tiny solar flares known as “campfires.”
The origins and behavior of these solar campfires are not well-understood, but they could play a role in one of the biggest mysteries about the Sun: Why is the corona, or solar atmosphere, so much hotter than the Sun’s surface?
Though campfires are millions of times weaker than normal solar flares emitted by our star, they may be a subtle heat source of the corona, though Solar Orbiter will need to collect more close measurements to figure out this enigma.
Right now, Solar Orbiter is in its “cruise phase,” meaning it is getting settled in its orbit around the Sun, but next year it will begin its “science phase,” which will bring it within the orbit of the solar system’s innermost planet, Mercury.
By 2022, the spacecraft will start tilting its trajectory away from the plane of the solar system so that it will fly over the Sun’s poles, which have never been directly imaged, let alone at a close distance.
Solar Orbiter is one of several next-generation Sun-watching observatories, located both in space and on Earth.
NASA’s Parker Solar Probe, launched in 2018, has already traveled closer to the Sun than any other spacecraft. By 2025, Parker will swoop within a record-breaking 4.3 million miles of the Sun’s surface, six times closer than Solar Orbiter will ever get.
That said, Parker’s proximity to the Sun means that it cannot take the kind of stunning images captured by Solar Orbiter, because the environment is too intense to allow for cameras to function. However, Parker has a sophisticated suite of instruments that will gather detailed data from inside the Sun’s atmosphere.
Back here on Earth, the Sun is being monitored by the newly operational Daniel K. Inouye Solar Telescope, located on the Hawaiian island of Maui. The telescope released its first images of the Sun—and the most detailed pictures of the solar surface ever taken—back in January.
Together, these new missions will help to constrain some of the biggest outstanding mysteries about the Sun, including the nature of its poles and the forces driving the solar wind, a stream of particles that influences environments throughout the solar system.
“We are all really excited about these first images,” said Müller in a statement. “But this is just the beginning,”