A closeup of the star cluster NGC 1929 shows what astronomers call a superbubble—a huge hole about 325 by 250 light-years across—being blown in a star-forming nebula.
The bubble, seen in this newly released shot from the European Southern Observatory, sits in the Large Magellanic Cloud, a small companion galaxy of our Milky Way. The bubble is being carved as radiation from massive, young stars and shockwaves from their explosive deaths push on the nebula's gas and dust.
Image courtesy Manu Mejias, ESO
The space shuttle Atlantis creates a bright trail through Earth's atmosphere in a picture of the shuttle's landing taken by an astronaut on the International Space Station. Atlantis touched down at Kennedy Space Center on July 21, bringing the U.S. shuttle program to an end.
(Get our full coverage of the final space shuttle mission.)
Photograph courtesy NASA
Galaxy With a Twist
The Milky Way is feeling kinky.
New images from the ESA Herschel Space Observatory show a mysterious shape to the dense ring of cold gas and dust that circles the center of our home galaxy. The ring appears as a yellow loop twisted into a figure eight in the false-color image above.
Astronomers had previously seen only parts of this ring—the Herschel shot is the first view of the entire structure, which stretches more than 300 light-years across. The scientists aren't yet sure why the kink in the ring exists, but it's thought the galaxy's ring structure in general was shaped by gravitational interactions with galactic companions, such as our large neighbor the Andromeda galaxy.
Image courtesy ESA/NASA/Caltech
The gentle slopes of a sand dune on Mars are seen in a recently released picture from the HiRISE camera on NASA's Mars Reconnaissance Orbiter.
Pictures such as this one are being used to help build the Mars Global Digital Dune Database, a U.S. Geological Survey project that aims to study the sizes, shapes, and movements of sand dunes for hints to the climatic and geologic processes happening on the red planet.
Image courtesy U-Arizona/NASA
A spike of light from a young star cuts across a newly released picture of NGC 2023, a star-forming nebula in the constellation Orion. The spike in the image, taken by the NASA/ESA Hubble Space Telescope, is an optical effect created by light scattered in the camera's optics.
This relatively cold cloud of dust and gas in space doesn't shine with its own radiated light, and instead is visible to Hubble because it's reflecting light from the brilliant star nearby. Red dots show where new stars are forming inside the dense nebula.
The 96-mile-wide (154-kilometer-wide) crater hosts a 3-mile-high (5 kilometer-high) mountain rich in layered deposits, which scientists hope will offer clues to Mars's watery past and its potential to host carbon-based life.
Image courtesy Caltech/NASA
A picture from a Japanese satellite shows Lake Sulunga, a 15.5-mile-wide (25-kilometer-wide) lake in Tanzania that straddles the border between the country's Dodoma and Singida regions.
A major road and a railway can be seen running north of the lake, while agricultural plots pepper the surrounding areas. The European Space Agency, which supported operations for the satellite, released the image on July 15.