Space Pictures This Week: Solar Flare, Green Aurora

Biggest Solar Eruption?
Image courtesy SDO/NASA
A solar flare on June 7 unleashed a massive eruption on the sun (pictured)—perhaps the biggest ever recorded, scientists say. (Watch a video of the solar flare.)
The solar flare itself—an unusually bright spot on the sun—was only a "moderate" event. Space observatories in the past year recorded about 70 such solar flares, each roughly ten times weaker than "extreme" flares, of which only two have occurred since 2007.
(Related: "Biggest Solar Flare in Years—Auroras to Be Widespread Tonight?")
Instead, what shocked scientists was the unusual amount of material that lofted up, expanded, and fell back down over roughly half the surface area of the sun. The event's simultaneous launch of particles into space is called a coronal mass ejection.
Published June 10, 2011
Aurora Over the Yukon
Photograph by Yuichi Takasaka, TWAN
As seen through a fisheye lens, a green aurora arcs above northwestern Canada's Yukon Territory in early May.
Taken at midnight, the picture also shows stars trailing around the north celestial pole—the point in the sky around which all the stars observed from the Northern Hemisphere rotate.
(See more aurora pictures.)
Published June 10, 2011
Mars's South Pole
Image courtesy ESA
Springtime at Mars's icy south pole is seen in an image released June 7 by the European Space Agency.
Most of the image, taken by the Mars Express orbiter, shows the southern polar ice cap and other scattered ice deposits. Some dark, dusty material (left) covers part of the ice cap.
Fewer than 620 miles (a thousand kilometers) from Mars's geographic south pole, the ice here is a relatively thin at 1,640 feet (500 meters) deep. By contrast, the ice at the pole can extend to more than 2.3 miles (3.7 kilometers) deep.
(See "Mars Pole Holds Enough Ice to Flood Planet, Radar Study Shows.")
Published June 10, 2011
Bitten Sun
Photograph by Thilo Bubek
The June 1 partial solar eclipse shines over Tromsø in northern Norway.
Visible from far-northern parts of the Europe and Asia—including areas where the sun doesn't set during this time of year—the eclipse at times turned the sun into a glowing "smile" hugging the horizon.
"We had a lot of clouds at the sky earlier in the evening, but fortunately there was a perfect sight on the sun at the time of the eclipse," photographer Thilo Bubek said in an email.
(Related: "Solar Eclipse Tonight: Sun to Smile on Arctic.")
Published June 10, 2011
A Nebula Is Born
Image courtesy ESA/NASA
The Hubble Space Telescope captured two billowy objects—part of a nascent nebula—in an image released June 6. A nebula is a cloud of gas or dust in interstellar space.
The cosmic body, called IRAS 13208-6020, was formed from material shed by a central star. The relatively short-lived billowing phenomenon shown here gives astronomers a chance to observe the early stages of nebula development, according to the European Space Agency.
(See nebula pictures.)
Published June 10, 2011
Endeavour in Action
Photograph courtesy Thierry Legault and Emmanuel Rietsch
The space shuttle Endeavour docks at the International Space Station on May 29, as seen in a series of stills from a video taken from Pau, France. The shuttle is unloading its cargo, the Alpha Magnetic Spectrometer (AMS).

Designed by particle physicists at the European Center for Nuclear Research (CERN), the AMS studies the same types of particles that atom smashers such as the Large Hadron Collider are meant to produce.

(See "Space Shuttle Pictures: 12 Endeavour Images to Remember.")
Published June 10, 2011
River in Flux
Image courtesy Robert Simmon/DEM/NASA
In central Louisiana's stretch of the Mississippi River, years of human engineering have led to differing water elevations. In the above picture, dark green represents the lowest elevations—around 26 feet (8 meters)—and brighter green shows the highest—around 92 feet (28 meters).
Completed in the 1960s, the region's system of levees, locks, floodgates, and canals has so far successfully kept the river from meandering westward, as it has done several times over the centuries, according to NASA's Earth Observatory website.
(See "Flood Pictures: Mississippi River at Its Worst.")
Published June 10, 2011
Ready to Rumble
Photograph courtesy ESA
After a year in isolation, six men participating in the Mars500 experiment grin in a picture released by the European Space Agency on June 3.
The men have spent 365 days in a facility near Moscow that mimics nearly every aspect of a flight to Mars, an eventual goal of the ESA.
Their simulated craft is composed of four sealed interconnected cylinders. Each crew member has his own private cabin, and the team lives and works very much like the astronauts on the International Space Station.
"The dark side of this routine is that every day for the past year we woke up at the same time to do the same medical controls with the same devices: No weekend or holiday breaks for a year!" crew member Romain Charles wrote in his diary.
(See "Astronauts Could Ride Asteroids to Mars, Study Says.")
Published June 10, 2011