M1: The Crab Nebula from Hubble

This is the mess that is left when a star explodes. The Crab Nebula, the result of a supernova seen in 1054 AD, is filled with mysterious filaments. The filaments are not only tremendously complex, but appear to have less mass than expelled in the original supernova and a higher speed than expected from a free explosion. The featured image, taken by the Hubble Space Telescope, is presented in three colors chosen for scientific interest. The Crab Nebula spans about 10 light-years. In the nebula’s very center lies a pulsar: a neutron star as massive as the Sun but with only the size of a small town. The Crab Pulsar rotates about 30 times each second. [via NASA] https://ift.tt/2NXDR35
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Real Time Perseid

Bright meteors and dark night skies made this year’s Perseid meteor shower a great time for a weekend campout. And while packing away their equipment, skygazers at a campsite in the mountains of southern Germany found at least one more reason to linger under the stars, witnessing this brief but colorful flash with their own eyes. Presented as a 50 frame gif, the two second long video was captured during the morning twilight of August 12. In real time it shows the development of the typical green train of a bright Perseid meteor. A much fainter Perseid is just visible farther to the right. Plowing through Earth’s atmosphere at 60 kilometers per second, Perseids are fast enough to excite the characteristic green emission of atomic oxygen at altitudes of 100 kilometers or so. [via NASA] https://ift.tt/2wW3dYE

Saturn s North Polar Hexagon

In full view, the amazing six-sided jet stream known as Saturn’s north polar hexagon is shown in this colorful Cassini image. Extending to 70 degrees north latitude, the false-color video frame is map-projected, based on infrared, visible, and ultraviolet image data recorded by the Saturn-orbiting spacecraft in late 2012. First found in the outbound Voyager flyby images from the 1980s, the bizarre, long-lived feature tied to the planet’s rotation is about 30,000 kilometers across. At its center lies the ringed gas giant’s hurricane-like north polar storm. A new long term study of Cassini data has found a remarkable higher-altitude vortex, exactly matching the outlines of the north polar hexagon, that formed as summer approached the planet’s northern hemisphere. It appears to reach hundreds of kilometers above these deeper cloud tops, into Saturn’s stratosphere. [via NASA] https://ift.tt/2Q6nP8y

NGC 3682: Sideways Spiral Galaxy

What do spiral galaxies look like sideways? Featured is a sharp telescopic view of a magnificent edge-on spiral galaxy NGC 3628, a puffy galactic disk divided by dark dust lanes. Of course, this deep galactic portrait puts some astronomers in mind of its popular moniker, The Hamburger Galaxy. The tantalizing island universe is about 100,000 light-years across and 35 million light-years away in the northern springtime constellation Leo. NGC 3628 shares its neighborhood in the local Universe with two other large spirals M65 and M66 in a grouping otherwise known as the Leo Triplet. Gravitational interactions with its cosmic neighbors are likely responsible for the extended flare and warp of this spiral’s disk. [via NASA] https://ift.tt/2wHNYmi

Moon behind Lava Fountain

What’s happened to the Moon? Nothing, but something has happened to the image of the Moon. The heat from a volcanic lava fountain in the foreground has warmed and made turbulent the air nearby, causing passing light to refract differently than usual. The result is a lava plume that appears to be melting the Moon. The featured picture was taken as the full Sturgeon Moon was setting behind Mt. Etna as it erupted in Italy about one week ago. The picture is actually a composite of two images, one taken right after the other, with the same camera and lens. The first image was a quick exposure to capture details of the setting Moon, while the second exposure, taken after the Moon set a few minutes later, was longer so as to capture details of the faint lava jets. From our Earth, we can only see the Sun, Moon, planets, and stars as they appear through the distortion of the Earth’s atmosphere. This distortion can not only change the images of familiar orbs into unusual shapes, it can –unexpectedly at times — delay sunset and moonset by several minutes. [via NASA] https://ift.tt/2LUCrEP

A Powerful Solar Flare

It was one of the most powerful solar flares in recorded history. Occurring in 2003 and seen across the electromagnetic spectrum, the Sun briefly became over 100 times brighter in X-rays than normal. The day after this tremendous X 17 solar flare — and subsequent Coronal Mass Ejection (CME) — energetic particles emitted from the explosions struck the Earth, creating auroras and affecting satellites. The spacecraft that took these frames — SOHO — was put in a turtle-like safe mode to avoid further damage from this and subsequent solar particle storms. The featured time-lapse movie condenses into 10 seconds events that occurred over 4 hours. The CME, visible around the central sun-shade, appears about three-quarters of the way through the video, while frames toward the very end are progressively noisier as protons from the explosions strike SOHO’s LASCO detector. One this day in 1859, the effects of an even more powerful solar storm caused telegraphs on Earth to spark in what is known as the Carrington Event. Powerful solar storms such as these may create beautiful aurora-filled skies, but they also pose a real danger as they can damage satellites and even power grids across the Earth. [via NASA] https://ift.tt/2NEaX8a

On August 23, 2018 the identification and distribution of aerosols in the Earth’s atmosphere is shown in this dramatic, planet-wide visualization. Produced in real time, the Goddard Earth Observing System Forward Processing (GEOS FP) model relies on a combination of Earth-observing satellite and ground-based data to calculate the presence of types of aerosols, tiny solid particles and liquid droplets, as they circulate above the entire planet. This August 23rd model shows black carbon particles in red from combustion processes, like smoke from the fires in the United States and Canada, spreading across large stretches of North America and Africa. Sea salt aerosols are in blue, swirling above threatening typhoons near South Korea and Japan, and the hurricane looming near Hawaii. Dust shown in purple hues is blowing over African and Asian deserts. The location of cities and towns can be found from the concentrations of lights based on satellite image data of the Earth at night. [via NASA] https://ift.tt/2orIqHS