Northern lights may appear across Canada and northern U.S. late Tuesday night

Tuesday, August 3, 2010

Forecasters predict that northern lights could be visible to the naked eye late tonight and early tomorrow morning across Canada, northern parts of the U.S., and possibly the United Kingdom.

Solar storms caused a large ejection of plasma from the Sun’s surface on Sunday, and the plasma is heading directly towards Earth. The plasma, a cloud of rapidly moving hydrogen gas atoms and subatomic particles, is expected to reach us late Tuesday. The plasma will interact with the Earth’s magnetic field and atmosphere, which will cause northern lights, or aurora borealis, to be visible much further south than is usual. Northern lights usually appear as green or red rivers of lights across the sky.

“It’s the first major Earth-directed eruption in quite some time” said astronomer Leon Golub of the Harvard-Smithsonian Center for Astrophysics. The eruption was detected by NASA’s Solar Dynamics Observatory, which was launched in February 2010, and is currently orbiting the Earth.

The Sun goes through approximately eleven-year long activity cycles, with the last maximum occurring in 2001. Sunday’s eruption is a sign that the many years of inactivity is over, and the Sun is heading towards another maximum.