Explosion on the Sun sends “shock wave” of super-charged particles racing toward Mars Science Laboratory for May 31 collision
According to the spaceweather blog entry CME TARGETS MARS: “The magnetic canopy of sunspot AR1492 erupted on May 27th at 0551UT, producing a long-duration C3-class solar flare and hurling a coronal mass ejection (CME) toward Mars.
Analysts at the Goddard Space Weather Lab say the cloud – they call it a “cloud” will hit the MSL spacecraft (containing the Mars rover Curiosity) on May 31st at 0100 UT followed by Mars itself about 10 hours later.
Because NASA has done nothing to protect the spacecraft from CMEs, NASA has decided to avoid discussion of these threats until and unless one of these destructive, radioactive, radiation “clouds” damages navigation controls or ignites any of the highly explosive fuels and pyrotechnics that are essential to MSL operation.
MSL and Curiosity were designed to withstand a typical range of interplanetary radiation that they would encounter during the 2009 launch window. But a long list of problems in design and execution, especially navigation and landing software, set the MSL launch ahead to the end of 2011. And that was thebeginning of a historic, two-year-long cascade of solar storms and giant CME’s.
Coronal mass ejections expand away from the Sun at speeds as high as 2000 km per second. They carry up to ten billion tons (1016 grams) of plasma away from the Sun, NASA explains in a posting far away from any mention of MSL.
Coronal mass ejections were once thought to be initiated by solar flares. Although most are accompanied by flares, it is now understood that flares and CMEs are related phenomena, but one does not cause the other. This has important implications for understanding and predicting the effects of solar activity on the Earth and in space.
While a flare alone produces high-energy particles near the Sun, some of which escape into interplanetary space, a CME drives a shock wave which can continuously produce energetic particles as it propagates through interplanetary space.
When a CME reaches the Earth, its impact disturbs the Earth's magnetosphere, setting off a geomagnetic storm. A CME typically takes 3 to 5 days to reach the Earth after it leaves the Sun. Observing the ejection of CMEs from the Sun provides an early warning of geomagnetic storms. Only recently, with SOHO, has it been possible to continuously observe the emission of CMEs from the Sun and determine if they are aimed at the Earth.
One serious problem that can occur during a geomagnetic storm is damage to Earth-orbiting satellites, especially those in high, geosynchronous orbits. Communications satellites are generally in these high orbits. Either the satellite becomes highly charged during the storm and a component is damaged by the high current that discharges into the satellite, or a component is damaged by high-energy particles that penetrate the satellite. We are not able to predict when and where a satellite in a high orbit may be damaged during a geomagnetic storm.
Astronauts on the Space Station are not in immediate danger because of the relatively low orbit of this manned mission. They do have to be concerned about cumulative exposure during space walks. The energetic particles from a flare or CME would be dangerous to an astronaut on a mission to the Moon or Mars, however.