Close-up reveals tiny ‘campfires’ on the Sun

Every morning, something miraculous happens.

A 4.6-billion-year-old sphere of burning, hot plasma – one million times the size of the Earth – rises into the sky. Although the Sun is a staggering 152 million kilometres away, we can feel its heat on our skin as it turns night to day and keeps life on Earth humming along.

Now, a space probe has sent back incredible pictures of tiny flares in its outer atmosphere. These so-called “campfires” are a millionth the size of those visible from Earth. Delighted by the discovery, astronomers hope the images will help solve some of the mysteries of our nearest star.

Our burning obsession with the Sun goes back thousands of years. Ancient civilisations worshipped it as a deity, to be feared and obeyed. It was associated with the power of the Egyptian pharaohs, and Hindus continue to pray at dawn to Surya, the Sun god who rides a horse-drawn chariot across the sky.

As the source of life-preserving light, keeping the Sun happy has always been important. We may find strange the rituals of Aztec human sacrifice or the Sun Dance of the Lakota. But religious ceremonies are how many people throughout history have dealt with the fear that the Sun might not always be with us.

A vanishing Sun may sound far-fetched, especially on a summer’s day in the middle of a climate crisis.

But for millennia, solar eclipses and other optical phenomena have been interpreted as omens and portents. At other times, volcanic eruptions have blotted out the Sun, causing years without summers, and inspired apocalyptic myths of the end of the world.

So, unsurprisingly, predicting the Sun’s movements has always been a serious business. Over 4,000 years ago, a Chinese emperor is reported to have beheaded two astronomers for failing to foresee an eclipse. Christopher Columbus had more luck in 1504, when he used a lunar eclipse to escape starvation. Since Columbus, huge advances in physics and the power of telescopes have vastly increased our knowledge of the Sun and the heavens.

And, thanks to 20th-Century astrophysics, we can now calculate that our star has enough hydrogen fuel to burn for another five billion years. That’s 1.8 trillion sunrises to look forward to. An incredible feat of prediction and a resounding victory of science over superstition, and knowledge over ignorance.

Not so fast. The 18th-Century philosopher David Hume warned that predictions are based on the assumption that the future will resemble the past. What has always happened will continue to happen.

It’s a fair assumption, but that’s all it is. Our ancestors believed angry gods controlled the weather; we believe there are unchangeable laws of nature. But the future may have other ideas.

Hume’s problem of induction has troubled philosophers ever since. His scepticism is why scientists talk about probabilities, not certainties. It may not stop you from sleeping tonight, but it should give you pause for thought.

So, do we know the Sun will rise tomorrow?

Total eclipse

Yes, say some, we do. The philosophers are splitting hairs. We have sent probes out into the solar system and built powerful telescopes to monitor the movements of the stars and planets. We understand the Sun far better than our superstitious ancestors, and rely on much more than past experience or blind faith.

No, say others, we don’t. History is full of improbable and unlikely events, and belief systems that have come crashing down without warning. You can no more prove that the future will be like the past than the Sun worshipper can prove their rituals please the Sun god. We all will just have to wait and see.