Distance travelled ~ 714'327'200 km
While we have been enjoying the wonderful sunshine down on Earth (especially the recent record october warmth in the UK) - space has also been throwing up some pretty stunning weather. Yesterday, October 4th, a massive solar flare exploded from the surface on the far side of the Sun. It blasted a spectacular coronal mass ejection or CME into space. A CME is a massive burst of solar wind and plasma containing electrons and protons that blast out from the Sun's surface. They are associated with solar flares and tend to develop in areas of high solar activity such as Sun spots.
The October 4th CME was recorded by the Solar and Heliospheric Observatory
Scientists from the Goddard Space Weather Lab have plotted the course of the CME and discovered it is heading directly for the planet closest to the Sun, Mercury. The cloud of highly energised plasma and particles won't affect the planet but could disrupt the MESSENGER probe in orbit around Mercury.
To watch the moving image click here
It is possible that the CME may then hit Venus on Oct. 6th, but it is not predicted to hit Earth.
What happens when CME's hit Earth?
When CMEs do come our way the shockwave from the highly energized particles can cause a geomagnetic storm that can disrupt our magnetic shield. This can trigger dynamic auroras or Northern Lights [aurora borealis] in the northern hemisphere or Southern Lights [aurora australis] in the southern hemisphere. CMEs hitting earth can also cause disruption to radio transmissions, damage satellites and cause power cuts by knocking out electrical power cables.
They don't present a health risk for us on the surface because of our protective magnetic shield and atmosphere. But they can present problems for astronauts and even people in high altitude planes due to increased risk of exposure to radiation. But it is thought that any long-term health risk are unlikely.