Main Content
Published April 23, 2010
NASA's new Solar Dynamics Observatory may be getting all the press this week for its retina-searing first pictures of the sun. But two old sun-observing warhorses recently showed they're not quite ready for pasture yet.
The twin, golf cart-size spacecraft of NASA's Solar Terrestrial Relations Observatory (STEREO) mission filmed, in ultraviolet light, the largest solar "prominence" in 15 years, according to the space agency. (See the video above, which compresses about 19 hours of solar activity on April 12 and 13).
Stretching nearly halfway across the sun, the looping eruption of ionized helium "is definitely one of the largest" solar prominences ever witnessed, said Madhulika Guhathakurta, a STEREO program scientist at NASA headquarters in Washington, D.C.
(See more pictures of solar eruptions.)
Solar Eruptions Still Something of a Mystery
The looping, gaseous eruptions are linked to changes in the strength of the sun's magnetic field, though the details of how solar prominences form remain an active area of research, Guhathakurta said.
Often when a prominence is rising above the surface of the sun, the magnetic field becomes so stressed that the gaseous loop "actually erupts, opens up," creating what's known as a coronal mass ejection, expelling "a huge amount of material into space," she said.
Coronal mass ejections can send bursts of charged particles, called solar wind, streaming toward Earth, where they can overload our planet's magnetic shield, knocking out satellite communications and power grids.
(Read "Magnetic-Shield Cracks Found; Big Solar Storms Expected.")
The eruption in the video, though, was directed away from Earth, so the effects on our planet, if any, were negligible, Guhathakurta said.
The detection of the giant eruption, she added, is an indication that, after a few years of subdued solar activity, "we are entering a phase of the solar cycle where activity is gradually picking up."
Most Popular News
-
Moon Water Linked to Silver?
The moon's south pole hosts unexpected amounts of silver and mercury, which may help reveal the origins of lunar water.
-
Oldest Human in China Found?
A fossil jawbone with a strong chin is upsetting notions of when our ancestors migrated out of Africa, a new study says.
-
Photos: Mummies Found on Pyramid
Wearing a false head, a bundled mummy—and three child sacrifices—emerge from an urban pyramid in Peru.
Advertisement
News Blogs
-
Living Walls Save Lions
A successful new project is using a chain-link fencing and fast-growing trees to create special enclosures that keep cattle safe from lions, and lions out of the way of Maasai spears.
-
Asteroid to Cause Sunburn?
A new model shows how an ocean impact would drastically alter the atmosphere, leading to dangerous levels of ozone depletion.
-
Dam Removals Restore Habitats
As dams come down around the world, opportunities are opened to restore habitats and cultural sites sacred to indigenous peoples.
Popular on Facebook
Gulf Oil Spill News and Pictures
-
Did Gulf Spill Boost "Dead Zone"?
Did the BP oil spill sap oxygen from the Gulf of Mexico? Scientists are weighing new findings against years of "dead zone" data.
-
Gulf Manta Rays Affected by Oil Spill?
The little-studied Gulf of Mexico's manta rays could be their own species—and victims of the oil spill, scientists say.
Shop National Geographic
Buy 2 or more DVDs and save 20%
Special Ad Section
-
View Entries
Over 14,000 photographs were submitted to the contest. See a selection of entries!
-
Watch Video
Watch Casey Anderson with his lovable best friend Brutus, the 800-pound bear he raised from birth.