A joint mission between NASA and the European Space Agency has yielded the closest photos of the sun ever taken. And with their release on Thursday, these swirly snapshots are newly available to the public.
The Solar Orbiter probe launched in early February, and completed its first close pass of the sun — within 48 million miles — in mid-June.
Other spacecraft have gotten closer, but did not carry sun-facing imagers.
"These unprecedented pictures of the Sun are the closest we have ever obtained," said Holly Gilbert, NASA project scientist for the mission at the Goddard Space Flight Center. "These amazing images will help scientists piece together the Sun's atmospheric layers, which is important for understanding how it drives space weather near the Earth and throughout the solar system."
#SolarOrbiter has made its first close pass by the Sun, studying our star and space with a comprehensive suite of instruments — and the data is already revealing previously unseen details. This is #TheSunUpClose. https://t.co/rVMjz45DoY pic.twitter.com/YLKBXRNQZb— NASA Sun & Space (@NASASun) July 16, 2020
Scientists involved in the mission said that while the first images from a spacecraft typically only serve to confirm that its instruments are working, these photographs reveal an unprecedented level of detail.
"We didn't expect such great results so early," said Daniel Müller, ESA's Solar Orbiter project scientist. "These images show that Solar Orbiter is off to an excellent start."
The spacecraft carries six imaging instruments that each study a different aspect of the sun. One of them, the Extreme Ultraviolet Imager, captured tiny bright spots among the swirls of yellow and gray.
Principal investigator David Berghmans, an astrophysicist at the Royal Observatory of Belgium in Brussels, called those spots "campfires."
"The campfires we are talking about here are the little nephews of solar flares, at least a million, perhaps a billion times smaller," he said. "When looking at the new high resolution EUI images, they are literally everywhere we look."
To know for certain what these campfires are and what they mean, scientists will need to use a different instrument on the spacecraft to take a more precise temperature measurement.
The discovery comes at the very beginning of a years-long mission, which aims to provide the first-ever look at the sun's poles.
Operators will use the gravity of Venus to gradually shift the spacecraft's orbit out of the plane in which planets in the Solar System orbit the sun, giving Solar Orbiter an unprecedented view of the sun's poles. Scientists are keen to study activity there in order to better understand the behavior of the sun's magnetic field, which helps create the solar wind that impacts the environment of the entire solar system.
Space weather can affect spacecraft and even humans on Earth because of potential impacts on satellites, GPS and the power grid.
Solar Orbiter is expected to be in a so-called cruise phase until November 2021, after which it will begin the primary phase of its mission. NASA said the spacecraft's first close pass by the sun in 2022 will be at "about a third the distance" from the sun to Earth.
Gilbert said at a Wednesday press briefing that the initial batch of images is an encouraging sign.
"I think most importantly it demonstrates that we are going to be able to accomplish our solar objectives of Solar Orbiter," she said. "We are very excited that everything is working, and it also confirms the importance of looking at different physical scales. If we've already made some discoveries in just the first sight images, just imagine what we're going to find when we get closer to the sun and when we get out of the ecliptic [plane]."