Today’s post is from science reference librarian Margaret Clifton. She is also the author of Stars in his Eyes , in which she discusses Galileo’s Sidereus nuncius – The Starry Messenger.
Coronal Mass Ejection as viewed by the Solar Dynamics Observatory on June 7, 2011. Credit: NASA/SDO
Since February the Sun has been kicking out some terrific solar flares as it moves from a quiet period toward the peak of Solar Cycle 24. That makes for some fantastic images from NASA and potentially some electrical grid problems here on Earth.
Sunspots had been recorded since before Galileo drew them in the early 1600s (they were observed and recorded by the Chinese astronomer Gan De as early as 364 BC). Back on Sept.1, 1859 the largest solar flare on record was witnessed by British astronomer Richard Carrington who sketched them and then published a description in Monthly Notices of the Royal Astronomical Society.
In 1859 the idea that they might have some effect on Earth hadn’t occurred to anyone yet. There was no such thing as an electrical grid, or telecommunications networks. There were, however, telegraph networks and the long wires of the network in France became the antennae for solar energy, heating up transmitters, some of which caught on fire.
Today the damage potential is far greater: communications satellites can be knocked out, astronauts have to take shelter in a special module in the space station, pipelines can be damaged, GPS systems whacked, flights re-routed, and potentially most damaging of all, the electrical grid could be knocked out across parts of North America for years.
Dean Pesnell, a NASA scientist who recently spoke at the Library on “The Many Colors of the Sun” (part of our ongoing series of NASA speakers), studies how solar activity is created and how “Space Weather” comes from that activity. They have posted some amazing video files here.
Pesnell says that the current period of solar activity should peak in 2013/2014, and predicting the flares is tricky business. When one happens, the solar storm that follows within 20 hours or so, generates a wave of charged particles that can literally deform the Earth’s magnetic field, charge the atmosphere and induce electric currents in power lines for several hours. Alerts come from NASA 12-14 hours before such a storm hits, and precise alerts generated by a NASA satellite called the Advanced Composition Explorer (ACE) are sent to power companies just 20 to 30 minutes before the storm strikes.
And then what? Will the lights go out Inside Adams?