Aurora Slathers up the Sky Aurora Slathers up the Sky

Like salsa verde on your favorite burrito, a green aurora slathers up the sky in this June 25 snapshot from the International Space Station. About 400 kilometers (250 miles) above Earth, the orbiting station is itself within the upper realm of the auroral displays. Aurorae have the signature colors of excited molecules and atoms at the low densities found at extreme altitudes. Emission from atomic oxygen dominates this view. The tantalizing glow is green at lower altitudes, but rarer reddish bands extend above the space station's horizon. The orbital scene was captured while passing over a point south and east of Australia, with stars above the horizon at the right belonging to the constellation Canis Major, Orion's big dog. Sirius, alpha star of Canis Major, is the brightest star near the Earth's limb. via NASA http://ift.tt/2eSjeJ1

Noodle Mosaic of Saturn Noodle Mosaic of Saturn

On April 26 the Cassini spacecraft swooped toward Saturn on the first of its Grand Finale dives between Saturn and rings. In this long, thin, noodle mosaic, a rapid series of 137 low resolution images captured by Cassini's wide-angle camera track its progress across the gas giant's swirling cloud tops. The mosaic projection maps the arc along Saturn's atmospheric curve on to a flat image plane. At top, the first mosaic panel is centered at 90 degrees north, about 72,400 kilometers above Saturn's dark north polar vortex. As the mosaic progresses it narrows, the pixel scale shrinking from 8.7 kilometers to 1 kilometer per pixel. For the last panel, the spacecraft is 8,374 kilometers above a region 18 degrees north of Saturn's equator. Frame orientation changes near the bottom as Cassini rotates to maneuver its large, dish-shaped, high-gain antenna forward, providing a shield before crossing Saturn's ring plane. via NASA http://ift.tt/2tL8zqm

The Milky Way over Monument Valley The Milky Way over Monument Valley

You don't have to be at Monument Valley to see the Milky Way arc across the sky like this -- but it helps. Only at Monument Valley USA would you see a picturesque foreground that includes these iconic rock peaks called buttes. Buttes are composed of hard rock left behind after water has eroded away the surrounding soft rock. In the featured image taken in 2012, the closest butte on the left and the butte to its right are known as the Mittens, while Merrick Butte can be seen farther to the right. Green airglow fans up from the horizon. High overhead stretches a band of diffuse light that is the central disk of our spiral Milky Way Galaxy. The band of the Milky Way can be spotted by almost anyone on almost any clear night when far enough from a city and surrounding bright lights, but a sensitive digital camera is needed to capture these colors in a dark night sky. via NASA http://ift.tt/2uuSbY1

Int Ball Drone Activated on the Space Station Int Ball Drone Activated on the Space Station

What if you were followed around by a cute floating ball that kept taking your picture? Then you might be an astronaut on today's International Space Station (ISS). Designed by the Japan Aerospace Exploration Agency (JAXA), the JEM Internal Ball Camera -- informally "Int-Ball" -- is a bit larger than a softball, can float and maneuver by itself but also be controlled remotely, can take high resolution images and videos, and is not related to Hello Kitty. Int-Ball was delivered to the ISS in early June and is designed to allow ground-control to increase the monitoring of ISS equipment and activities while decreasing time demands on human astronauts. Int-Ball moves by turning on small internal fans and sees with a camera located between its two dark eyes. via NASA http://ift.tt/2urdlX8

A Hybrid Solar Eclipse over Kenya A Hybrid Solar Eclipse over Kenya

Chasing solar eclipses can cause you to go to the most interesting places and meet the most interesting people. Almost. For example, chasing this eclipse brought this astrophotographer to Kenya in 2013. His contact, a member of the Maasai people, was to pick him up at the airport, show him part of southern Kenya, and even agreed to pose in traditional warrior garb on a hill as the hopefully spectacular eclipse set far in background. Unfortunately, this contact person died unexpectedly a week before the astrophotographer's arrival, and so he never got to participate in the shoot, nor know that the resulting image went on to win an international award for astrophotography. Pictured in 2013 from Kenya, the Moon covers much of the Sun during a hybrid eclipse, a rare type of solar eclipse that appears as total from some Earth locations, but annular in others. During the annular part of the eclipse, the Moon was too far from the Earth to block the entire Sun. Next month a total solar eclipse will cross the USA. via NASA http://ift.tt/2tQTQVG

Mercury as Revealed by MESSENGER Mercury as Revealed by MESSENGER

Mercury had never been seen like this before. In 2008, the robotic MESSENGER spacecraft buzzed past Mercury for the second time and imaged terrain mapped previously only by comparatively crude radar. The featured image was recorded as MESSENGER looked back 90 minutes after passing, from an altitude of about 27,000 kilometers. Visible in the image, among many other newly imaged features, are unusually long rays that appear to run like meridians of longitude out from a young crater near the northern limb. MESSENGER entered orbit around Mercury in 2011 and finished its primary mission in 2012, but took detailed measurements until 2015, at which time it ran out of fuel and so was instructed to impact Mercury's surface. via NASA http://ift.tt/2vKLEaX

Apollo 11: Catching Some Sun Apollo 11: Catching Some Sun

Bright sunlight glints and long dark shadows mark this image of the lunar surface. It was taken July 20, 1969 by Apollo 11 astronaut Neil Armstrong, the first to walk on the Moon. Pictured is the mission's lunar module, the Eagle, and spacesuited lunar module pilot Buzz Aldrin unfurling a long sheet of foil also known as the Solar Wind Composition Experiment. Exposed facing the Sun, the foil trapped particles streaming outward in the solar wind, catching a sample of material from the Sun itself. Along with moon rocks and lunar soil samples, the solar wind collector was returned for analysis in earthbound laboratories. via NASA http://ift.tt/2uOGdeW

Phobos: Moon over Mars Phobos: Moon over Mars

A tiny moon with a scary name, Phobos emerges from behind the Red Planet in this timelapse sequence from the Earth-orbiting Hubble Space Telescope. Over 22 minutes the 13 separate exposures were captured near the 2016 closest approach of Mars to planet Earth. Martians have to look to the west to watch Phobos rise, though. The small moon is closer to its parent planet than any other moon in the Solar System, about 3,700 miles (6,000 kilometers) above the Martian surface. It completes one orbit in just 7 hours and 39 minutes. That's faster than a Mars rotation, which corresponds to about 24 hours and 40 minutes. So on Mars, Phobos can be seen to rise above the western horizon 3 times a day. Still, Phobos is doomed. via NASA http://ift.tt/2ubOmH8

IC 1396: Emission Nebula in Cepheus IC 1396: Emission Nebula in Cepheus

Stunning emission nebula IC 1396 mixes glowing cosmic gas and dark dust clouds in the high and far off constellation of Cepheus. Energized by the bright central star seen here, this star forming region sprawls across hundreds of light-years, spanning over three degrees on the sky while nearly 3,000 light-years from planet Earth. Among the intriguing dark shapes within IC 1396, the winding Elephant's Trunk nebula lies just below center. Stars could still be forming inside the dark shapes by gravitational collapse. But as the denser clouds are eroded away by powerful stellar winds and radiation, any forming stars will ultimately be cutoff from the reservoir of star stuff. The gorgeous color view is a composition of image data from narrowband filters, mapping emission from the nebula's atomic oxygen, hydrogen, and sulfur into blue, green, and red hues. via NASA http://ift.tt/2vgKUex

Ireson Hill on Mars Ireson Hill on Mars

What created this unusual hill on Mars? Its history has become a topic of research, but its shape and two-tone structure makes it one of the more unusual hills that the robotic Curiosity rover on Mars has rolled near. Dubbed Ireson Hill, the mound rises about 5 meters high and spans about 15 meters across. Ireson Hill is located on the Bagnold Dune field on the slope of Mount Sharp in Gale Crater on Mars. The featured 41-image panorama has been horizontally compressed to include the entire hill. The image was taken on February 2 and released last week. Because Mars is moving behind the Sun as seen from the Earth, NASA will soon stop sending commands to its Martian orbiters and rovers until about August 1. via NASA http://ift.tt/2uCRIpD