Closest ever pictures taken of the Sun

Science & Technology

New pictures of the Sun taken just 77 million km (48 million miles) from its surface are the closest ever acquired by cameras.

They come from the European Space Agency’s Solar Orbiter (SolO) probe, which was launched earlier this year.

Among the UK-assembled craft’s novel insights are views of mini-flares dubbed “camp fires”.

These are millionths of the size of the Sun’s giant flares that are routinely observed by Earth telescopes.

Whether these miniature versions are driven by the same mechanisms, though, is unclear. But these small flares could be involved in the mysterious heating process that makes the star’s outer atmosphere, or corona, far hotter than its surface.

“The Sun has a relatively cool surface of about 5,500 degrees and is surrounded by a super-hot atmosphere of more than a million degrees,” explained Esa project scientist Daniel Müller.

“There’s a theory put forward by the great US physicist Eugene Parker, who conjectured that if you should have a vast number of tiny flares this might account for an omnipresent heating mechanism that could make the corona hot.”

Whatever their role, the camp fires are certainly small – which may explain why they’ve been missed up to this point, says David Berghmans, from the Royal Observatory of Belgium and the principal investigator on the probe’s Extreme Ultraviolet Imager (EUI).

“The smallest ones are a couple of our pixels. A pixel corresponds to 400km – that’s the spatial resolution. So they’re about the size of some European countries,” he told reporters. “There may be smaller ones.”