Watching solar storms in Stereo

Twin satellites will blast into space next week to take amazing 3D pictures of explosions on the Sun. The two probes, one on either side of the Earth, will act like a pair of giant eyes millions of miles apart.

An artist’s impression showing the Stereo satellites in action. Image credit: NASA

The £250 million, UK-backed Nasa mission, called Stereo, is due to launch on Wednesday from Cape Canaveral in Florida. For the first time, it will give scientists a unique view of the sun and space weather in three dimensions.

The two satellite observatories, each the size of a fridge, will watch for massive, violent eruptions from sunspots that can hurl billions of tons of hot gas towards our planet, causing dazzling aurorae.

The biggest explosions, equal to letting off billions of nuclear bombs, could zap communications satellites, disrupt power supplies and even put astronauts’ lives in peril.

Mystery of Sun’s corona solved

Storms are expected to build up and worsen over the next few years as the sun goes through its 11-year cycle of activity. Experts say that the worst storms – called coronal mass ejections – could cause as much economic damage as a major hurricane or tsunami.

The most powerful yet seen, in 1859, would today cause £40 billion of damage by destroying hundreds of satellites and wrecking power and communications networks.

A more recent blast from a sunspot in 1989 caused millions of pounds worth of damage to power supplies around the world. And violent explosions in January last year would have made any spacewalking astronauts very sick from radiation poisoning.

UK astronomers will work with data from the Stereo observatories, one of which will fly ahead of the Earth’s orbit and one which will trail us in space.

Solar explosions expert Dr Lucie Green, of the Mullard Space Science Laboratory in Surrey, told me today: “We want to understand how the Sun functions.

“When the hot gases from an eruption stream into the Earth’s atmosphere, the whole impact shakes up our magnetic field. That can cause all kinds of navigational and communications problems – even pigeons and other animals that navigate using the Earth’s magnetic field can get lost!”

★ Keep up with space news and observing tips. Click here to sign up for alerts to our latest reports. No spam ever - we promise!