Monday, 2 August 2010

Nasa scientists braced for 'solar tsunami' to hit earth

The earth could be hit by a wave of violent space weather as early as Tuesday after a massive explosion of the sun, scientists have warned.

 
Sunspot 1092
Sunspot 1092 may combine with a large filament of cool gas stretching across the sun's northern hemisphere to produce interference with communication systems on Earth Photo: NASA

The solar fireworks at the weekend were recorded by several satellites, including Nasa’s new Solar Dynamics Observatory which watched its shock wave rippling outwards.

Astronomers from all over the world witnessed the huge flare above a giant sunspot the size of the Earth, which they linked to an even larger eruption across the surface of Sun.

The explosion was aimed directly towards Earth, which then sent a “solar tsunami” racing 93 million miles across space.

Images from the SDO hint at a shock wave travelling from the flare into space, the New Scientist reported.

Experts said the wave of supercharged gas will likely reach the Earth on Tuesday, when it will buffet the natural magnetic shield protecting Earth.

It is likely to spark spectacular displays of the aurora or northern and southern lights.

Scientists have warned that a really big solar eruption could destroy satellites and wreck power and communications grids around the globe if it happened today.

Nasa recently warned that Britain could face widespread power blackouts and be left without critical communication signals for long periods of time, after the earth is hit by a once-in-a-generation “space storm”.

The Daily Telegraph disclosed in June that senior space agency scientists believed the Earth will be hit with unprecedented levels of magnetic energy from solar flares after the Sun wakes “from a deep slumber” sometime around 2013.

It remains unclear, however, how much damage this latest eruption will cause the world’s communication tools.

Dr Lucie Green, of the Mullard Space Science Laboratory, Surrey, followed the flare-ups using Japan's orbiting Hinode telescope.

"What wonderful fireworks the Sun has been producing,” the UK solar expert said.

“This was a very rare event – not one, but two almost simultaneous eruptions from different locations on the sun were launched toward the Earth.

"These eruptions occur when immense magnetic structures in the solar atmosphere lose their stability and can no longer be held down by the Sun's huge gravitational pull. Just like a coiled spring suddenly being released, they erupt into space.”

She added: "It looks like the first eruption was so large that it changed the magnetic fields throughout half the Sun's visible atmosphere and provided the right conditions for the second eruption.

"Both eruptions could be Earth-directed but may be travelling at different speeds.

“This means we have a very good chance of seeing major and prolonged effects, such as the northern lights at low latitudes."

A Nasa spokesman was unavailable for comment.