Bright Spiral Galaxy M81 Bright Spiral Galaxy M81

One of the brightest galaxies in planet Earth's sky is similar in size to our Milky Way Galaxy: big, beautiful M81. This grand spiral galaxy can be found toward the northern constellation of the Great Bear (Ursa Major). This superbly detailed view reveals M81's bright yellow nucleus, blue spiral arms, and sweeping cosmic dust lanes with a scale comparable to the Milky Way. Hinting at a disorderly past, a remarkable dust lane actually runs straight through the disk, to the left of the galactic center, contrary to M81's other prominent spiral features. The errant dust lane may be the lingering result of a close encounter between M81 and its smaller companion galaxy, M82. Scrutiny of variable stars in M81 has yielded one of the best determined distances for an external galaxy -- 11.8 million light-years. via NASA http://ift.tt/2x9X8bS

100 Steps Forward 100 Steps Forward

A beautiful conjunction of Venus and Moon, human, sand, and Milky Way is depicted in this night skyscape from planet Earth. The scene is a panorama of 6 photos taken in a moment near the end of a journey. In the foreground, footsteps along the wind-rippled dunes are close to the Huacachina oasis in the southwestern desert of Peru. An engaging perspective on the world at night, the stunning final image was also chosen as a winner in The World at Night's 2017 International Earth and Sky Photo Contest. via NASA http://ift.tt/2wYuhaU

Flare Well AR2673 Flare Well AR2673

Almost out of view from our fair planet, rotating around the Sun's western edge giant active region AR2673 lashed out with another intense solar flare followed by a large coronal mass ejection on September 10. The flare itself is seen here at the right in an extreme ultraviolet image from the sun-staring Solar Dynamics Observatory. This intense flare was the fourth X-class flare from AR2673 this month. The active region's most recent associated coronal mass ejection collided with Earth's magnetosphere 2 days later. Say farewell to the mighty AR2673, for now. For the next two weeks, the powerful sunspot group will be on the Sun's far side. via NASA http://ift.tt/2xwBDDn

NGC 6334: The Cats Paw Nebula NGC 6334: The Cats Paw Nebula

Nebulas are perhaps as famous for being identified with familiar shapes as perhaps cats are for getting into trouble. Still, no known cat could have created the vast Cat's Paw Nebula visible in Scorpius. At 5,500 light years distant, Cat's Paw is an emission nebula with a red color that originates from an abundance of ionized hydrogen atoms. Alternatively known as the Bear Claw Nebula or NGC 6334, stars nearly ten times the mass of our Sun have been born there in only the past few million years. Pictured here is a deep field image of the Cat's Paw Nebula in light emitted by hydrogen, oxygen, and sulfur. via NASA http://ift.tt/2wUOfn6

Calm Waters and Geomagnetic Storm Calm Waters and Geomagnetic Storm

Very recognizable stars of the northern sky are a backdrop for calm waters in this moonlit sea and skyscape off Cape Cod, Massachusetts. Taken on September 7, the photo also records a colorful display of northern lights or aurora borealis triggered by a severe geomagnetic storm. Visible crossing the Sun, the giant solar active region responsible, AR 2673, is much larger than planet Earth. It has produced the strongest flare of the current solar cycle and and the Earth-directed coronal mass ejection in the last few days. via NASA http://ift.tt/2gRH9cN

The Great Gig in the Sky The Great Gig in the Sky

There were no crowds on the beach at Phillips Lake, Oregon on August 21. But a few had come there to stand, for a moment, in the dark shadow of the Moon. From the beach, this unscripted mosaic photo records their much anticipated solar eclipse. In two vertical panels it catches the last few seconds of totality and the first instant of 3rd contact, just as the eclipse ends and sunlight faintly returns. Across the US those gathered along the path of totality also took pictures and shared their moment. And like those at Phillips Lake they may treasure the experience more than any planned or unplanned photograph of the total eclipse of the Sun. via NASA http://ift.tt/2vND1kt

The Flash Spectrum of the Sun The Flash Spectrum of the Sun

In clear Madras, Oregon skies, this colorful eclipse composite captured the elusive chromospheric or flash spectrum of the Sun. Only three exposures, made on August 21 with telephoto lens and diffraction grating, are aligned in the frame. Directly imaged at the far left, the Sun's diamond ring-like appearance at the beginning and end of totality brackets a silhouette of the lunar disk at maximum eclipse. Spread by the diffraction grating into the spectrum of colors toward the right, the Sun's photospheric spectrum traces the two continuous streaks. They correspond to the diamond ring glimpses of the Sun's normally overwhelming disk. But individual eclipse images also appear at each wavelength of light emitted by atoms along the thin, fleeting arcs of the solar chromosphere. The brightest images, or strongest chromospheric emission, are due to Hydrogen atoms. Red hydrogen alpha emission is at the far right with blue and purple hydrogen series emission to the left. In between, the brightest yellow emission is caused by atoms of Helium, an element only first discovered in the flash spectrum of the Sun. via NASA http://ift.tt/2gLHEEU

The Climber and the Eclipse The Climber and the Eclipse

What should you do if your rock climbing picture is photobombed by a total eclipse of the Sun? Rejoice -- because your planning paid off. After months of considering different venues, and a week of scouting different locations in Oregon's Smith Rock State Park, a group of photographers and rock climbers led by Ted Hesser, Martina Tibell, and Michael Shainblum settled on picturesque 100-meter tall Monkey Face tower as the dramatic foreground for their images of the pending total solar eclipse. Tension mounted as the eclipse time approached, planned juxtapositions were scrutinized, and the placement of rock climber Tommy Smith was adjusted. Right on schedule, though, the Moon moved in front of the Sun, and Smith moved in front of the Moon, just as planned. The solar eclipse image displayed here actually shows a diamond ring, an eclipse phase when a bit of the distant Sun is still visible beyond the Moon's surface. via NASA http://ift.tt/2vIebmd

A Waterspout in Florida A Waterspout in Florida

What's happening over the water? Pictured here is one of the better images yet recorded of a waterspout, a type of tornado that occurs over water. Waterspouts are spinning columns of rising moist air that typically form over warm water. Waterspouts can be as dangerous as tornadoes and can feature wind speeds over 200 kilometers per hour. Some waterspouts form away from thunderstorms and even during relatively fair weather. Waterspouts may be relatively transparent and initially visible only by an unusual pattern they create on the water. The featured image was taken in 2013 July near Tampa Bay, Florida. The Atlantic Ocean off the coast of Florida is arguably the most active area in the world for waterspouts, with hundreds forming each year. Some people speculate that waterspouts are responsible for some of the losses recorded in the Bermuda Triangle. via NASA http://ift.tt/2xFhdVC

A First Glimpse of the Great American Eclipse A First Glimpse of the Great American Eclipse

Making landfall in Oregon, the Moon's dark umbral shadow toured the United States on August 21. Those gathered along its coast to coast path were witness to a total eclipse of the Sun, possibly the most widely shared celestial event in history. But first, the Moon's shadow touched the northern Pacific and raced eastward toward land. This dramatic snapshot was taken while crossing the shadow path 250 miles off the Oregon coast, 45,000 feet above the cloudy northern Pacific. Though from a shorter totality, it captures the eclipse before it could be seen from the US mainland. With the eclipsed Sun not far above, beautiful colors appear along the western horizon giving way to a clear, pitch-black, stratospheric sky in the shadow of the Moon. via NASA http://ift.tt/2wUvjFu