The Europe-led Solar Orbiter mission has captured a stunning sequence of the lively star at the center of our solar system as it made its closest approach amid intensifying solar activity.
The European Space Agency (ESA), which operates the spacecraft, released the sequence on the day of the spacecraft's closest approach, or perihelion, on Wednesday (Oct. 12). The images show 20 days of Solar Orbiter's observations of the star, taken between Sept. 20 and Monday (Oct. 10).
The images were taken with the spacecraft's high-resolution Extreme Ultraviolet Imager (EUI) operating in the full sun mode that enables scientists to view the entire star. The video reveals the rotating star sparkling with activity in its gaseous atmosphere, the corona, which reaches temperatures of up to 1.8 million degrees Fahrenheit (1 million degrees Celsius).
Scientists enhanced the colors in the sequence because human eyes cannot see the ultraviolet wavelength detected by the instrument, ESA said in a statement.
Solar Orbiter makes regular close passes of the sun at about one-third of the sun-Earth distance, within the orbit of the planet Mercury. On this flyby, the spacecraft's fifth, it reached the closest point to the sun today at 3:12 p.m. EDT (1912 GMT).
Solar Orbiter, launched in 2020, doesn't make as close dives toward the star as NASA's Parker Solar Probe, but unlike Parker carries high-resolution cameras that wouldn't survive in the extremely hot environment that Parker visits. Together, the two probes are enabling giant leaps in our understanding of the star at the center of our solar system.
Solar Orbiter also makes regular flybys of the planet Venus, using its gravity to gradually tilt its orbit out of the ecliptic plane in which planets orbit. These maneuvers will eventually allow Solar Orbiter to view the sun's poles in detail, which no spacecraft has done before. Scientists believe that the polar regions harbor clues about how the star generates its magnetic field, which in turn drives its 11-year cycle of activity, the ebb and flow in the production of sunspots, solar flares and eruptions.
Solar activity has been picking up over the past year, causing all sorts of problems in the near-Earth environment. Satellite operators have reported struggles with maintaining spacecraft orbits near the planet because the interaction of the solar wind, the stream of charged particles emanating from the sun, with Earth's atmosphere increased the drag experienced by the satellites. In February, SpaceX lost an entire batch of its Starlink internet satellites after launching into a mild geomagnetic storm caused by a solar eruption. A major solar flare disrupted radio communications in North America just as the U.S. was recovering from the rampage of Hurricane Ian.
Missions such as Solar Orbiter and the Parker Solar Probe will help scientists better understand the behavior of the star and predict its tantrums so that we can better protect technology on Earth and in space in the future.