Space Pictures This Week: Hubble Starburst, Sun Magnetism
Star Breeding GroundImage courtesy ESA/NASA
Confetti colors adorn the dwarf galaxy NGC 4214 in a composite picture from the NASA/ESA Hubble Space Telescope released Thursday.
The galaxy, about ten million light-years from Earth, is roiling with star formation. But astronomers have also seen clusters of much older stars dotted around this "starburst" galaxy, indicating that the current round of star births is not the first to happen in this part of space.
And the galaxy's abundant hydrogen—the main ingredient in stars—means that star birth in the region will likely continue far into the future.
Martian Faults
Image courtesy ESA
Deep fractures cut across the surface of the red planet in a recently released picture from the European Space Agency's Mars Express orbiter.
The image captures part of the Nili Fossae region, a collection of curved faults and troughs northwest of the ancient impact basin Isidis. The curves tend to follow the outline of the basin, suggesting the fractures formed in the aftermath of the impact.
Here Comes the Sun
Image courtesy SDO/NASA
NASA's Solar Dynamics Observatory recently zoomed in on an active region of the sun, capturing this image of plasma—charged gas—streaming back and forth along magnetic field lines.
SDO watched as the suspended plasma, glowing red hot in extreme ultraviolet light, shuttled above the sun's surface for more than two days.
Raging Winds
Illustration courtesy AOES Medialab/ESA
Molecular winds flow from a galaxy in an artist's rendering. With its powerful infrared vision, the European Space Agency's Herschel space telescope has detected raging winds of molecular gas streaming away from galaxies—with the fastest gales reaching 621 miles (1,000 kilometers) a second.
Scientists had suspected such winds might exist, but Herschel's data marks the first time they've been definitively spotted. It's thought the outflows are stripping galaxies of the raw material for star formation, although what exactly drives the winds is still a mystery.
Tibetan Delta
Photograph courtesy NASA
Rust-colored sediments flow into the turquoise waters of Lake Ayakum in an astronaut picture of the Tibetan Plateau released May 9.
When sediments build up to the point that a river can no longer flow over them, the river will jump to a new channel. Over time, these channels tend to sweep back and forth to form the fan shape typical of river deltas. This image shows two currently active river deltas nestled in smooth, older surfaces (tan), which mark the previous positions of the river channels.
Honey Prairie Fire
Image courtesy Landsat/NASA
On May 8 NASA's Landsat-7 satellite captured this picture of smoke billowing from the Honey Prairie Fire in southern Georgia's Okefenokee Swamp.
Sparked by lightning, the wildfire has so far burned about 61,822 acres (25,018 hectares) of scrub and brush. But fire managers in Okefenokee National Wildlife Refuge aren't too worried: Fires are a natural part of the swamp's ecosystem, clearing land for fresh prairie grass. Firefighters are working to keep the blaze within the refuge, and they expect heavy summer rains will eventually put the fires out.
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