Analysis shows that mini jets of gas help to generate the solar wind, a discovery that also illuminates how our star’s activity damages satellites.

Tiny bursts of superheated gas could fuel the stream of charged particles that rushes outwards from the Sun’s surface at hundreds of kilometres per second, a study1 shows. The origin of this powerful ‘solar wind’ has been a mystery for decades.

The discovery reveals fresh details about where the wind begins and how it is created. This is important for understanding why the Sun occasionally belches out extremely large bursts of particles, which can wash over Earth and generate glowing auroras while also damaging satellites.

“What we are observing ... could actually be a substantial source of the solar wind,” says Lakshmi Pradeep Chitta, a solar physicist at the Max Planck Institute for Solar System Research in Göttingen, Germany. He and his colleagues describe the finding today in Science.

Sizzling hot mission
The scientists used the European Space Agency’s Solar Orbiter spacecraft to spot the newfound jets issuing from the Sun’s atmosphere. They dubbed them ‘picoflare jets’, because they have approximately one-trillionth the energy of the largest flares the Sun can produce, and the prefix ‘pico’ refers to 10^(–12.)

Solar Orbiter snapped pictures of the picoflare jets in March 2022, as the spacecraft whizzed past the Sun’s south pole. The high-resolution images reveal dark streaks, each a few hundred kilometres long, that appear and then, after 20–100 seconds, disappear...

...The high-resolution images reveal dark streaks, each a few hundred kilometres long, that appear and then, after 20–100 seconds, disappear. In that short lifespan, a jet emits as much energy as is consumed by 3,000–4,000 households in the United States over an entire year, Chitta says...

...The Sun is currently approaching, or might have already reached, the peak of its 11-year cycle of activity, when a high number of sunspots dapple its surface and there are frequent large solar flares, which are eruptions of radiation. This July and August, three of the largest solar flares thought to be possible, known as X-class flares, erupted from the Sun. The 7 August flare created a strong radio blackout on Earth that interfered with navigation signals.

The high levels of activity are giving solar scientists plenty to look at, says Andrei Zhukov, a solar physicist at the Royal Observatory of Belgium in Brussels...