A rarely seen total eclipse of the Sun in Antarctica on December 4 is drawing the attention of an international partnership of scientists who hope to learn more about the effects of such eclipses on space weather. The eclipse begins at 0700 GMT and can only be seen in Antarctica, with the path of totality running across the Ronne ice shelf and Ellsworth land.
Space weather, which describes how magnetic fields, charged particles, and gas molecules interact near the Earth, is an increasingly important subject because of its ability to affect satellite functions, international communications, and even national power grids, as well as giving rise to the Northern and Southern Lights.
Not surprisingly, the Sun plays a major role in such weather and the proximity of the South Magnetic Pole in Antarctica produces dramatic local interactions, so researchers have launched a multi-national campaign to study the effects of shutting off radiation from the Sun by the Moon on the region and the Earth as a whole.
This campaign focuses on the British Antarctic Survey's eight Low-Power Magnetometers (LPM). One of these is directly in the path of totality and the other seven are spread around the continent, which will allow the team to study changes in magnetic variations as the changes in electrical resistance in the upper atmosphere alters electrical currents at that altitude range. These can produce "traveling ionospheric disturbances" that can have global effects and affect satellite navigation systems.
"The team here are really excited about being able to witness the eclipse on Saturday morning," says John Law, Antarctic Atmospheric Scientist at Rothera station. "We will be setting our alarm clocks for the early hours, the maximum amount of Sun that will be hidden by the Moon will be around 94 percent around 4 am [local time] in the morning. During the summer, the sun never sets below the horizon so even at 4 am we should see the effect of the eclipse. The Sun will be low in the sky, hopefully just above the mountains of the Antarctic Peninsula to the east of us. As a meteorologist I am normally a big fan of clouds but on this one occasion I’m hoping they stay away."
The next total eclipse in Antarctica will be on December 15, 2039.
Source: British Antarctic Survey