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Every one of us contains alien atoms that originated in a galaxy far, far away, a new study suggests. Scientists have discovered that up to half the matter making up our galaxy, the Milky Way, used to belong to other clusters of stars. The sun, the Earth, and even our own bodies probably contain a large proportion of this galaxy-hopping material, which migrated to our part of the universe across vast expanses of space. Lead researcher Dr Daniel Angles-Alcazar, from Northwestern University in the US, said: “Given how much of the matter out of which we formed may have come...

The Milky Way appears as a relatively flat structure when viewed along its plane in visible light. Gamma-ray emission, however, paints a different picture: two huge structures billowing outward from the galaxy’s bulge like an enormous hourglass. Named the Fermi Bubbles, these structures are the result of the Milky Way’s supermassive black hole gorging itself on interstellar gas in the past. Using the Hubble Space Telescope (HST), astronomers have now determined just when these structured formed. A team of astronomers led by Rongmon Bordoloi of the Massachusetts Institute of Technology has used distant quasars to trace the structure and motion...

Explanation: A remarkable telescopic composition in yellow and blue, this scene features a trio of interacting galaxies almost 90 million light-years away, toward the constellation Virgo. On the right, two, spiky, foreground Milky Way stars echo the trio galaxy hues, a reminder that stars in our own galaxy are like those in the distant island universes. With sweeping spiral arms and obscuring dust lanes, NGC 5566 is enormous, about 150,000 light-years across. Just above it lies small, blue NGC 5569. Near center, the third galaxy, NGC 5560, is multicolored and apparently stretched and distorted by its interaction with NGC 5566....

Explanation: This beautiful telephoto composition spans light-years in a natural night skyscape from the island of Crete. Looking south, exposures both track the stars and record a fixed foreground in three merged panels that cover a 10x12 degree wide field of view. The May 15 waxing gibbous moonlight illuminates the church and mountainous terrain. A mere 18 thousand light-years away, huge globular star cluster Omega Centauri (NGC 5139) shining above gives a good visual impression of its appearance in binoculars on that starry night. Active galaxy Centaurus A (NGC 5128) is near the top of the frame, some 11 million...

New Map Shows the Dark Side of Artificial Light at Night ... The most fundamental difficulty, however, has been that no one knows exactly how severe the problem is.

The luminous glow of light pollution prevents nearly 80 percent of people in North America from seeing the Milky Way in the night sky. That's according to a new atlas of artificial night sky brightness that found our home galaxy is now hidden from more than one-third of humanity.

Explanation: This sharp telescopic field of view holds two bright galaxies. Barred spiral NGC 5101 (top right) and nearly edge-on system NGC 5078 are separated on the sky by about 0.5 degrees or about the apparent width of a full moon. Found within the boundaries of the serpentine constellation Hydra, both are estimated to be around 90 million light-years away and similar in size to our own large Milky Way galaxy. In fact, if they both lie at the same distance their projected separation would be only 800,000 light-years or so. That's easily less than half the distance between the...

Explanation: That's not lightning, and it did not strike between those mountains. The diagonal band is actually the central band of our Milky Way Galaxy, while the twin peaks are actually called the Spanish Peaks -- but located in Colorado, USA. Although each Spanish peak is composed of a slightly different type of rock, both are approximately 25 million years old. This serene yet spirited image composite was meticulously created by merging a series of images all taken from the same location on one night and early last month. In the first series of exposures, the background sky was built...

Explanation: In this early May night skyscape, a mountain road near Bursa, Turkey seems to lead toward bright planets Mars and Saturn and the center of our Milky Way Galaxy, a direction nearly opposite the Sun in planet Earth's sky. The brightest celestial beacon on the scene, Mars, reaches its opposition tonight and Saturn in early June. Both will remain nearly opposite the Sun, up all night and close to Earth for the coming weeks, so the time is right for good telescopic viewing. Mars and Saturn form the tight celestial triangle with red giant star Antares just right of...

Explanation: On May 6, the after midnight launch of a SpaceX Falcon 9 rocket lit up dark skies over Merritt Island, planet Earth. Its second stage bound for Earth orbit, the rocket's arc seems to be on course for the center of the Milky Way in this pleasing composite image looking toward the southeast. Two consecutive exposures made with camera fixed to a tripod were combined to follow rocket and home galaxy. A 3 minute long exposure at low sensitivity allowed the rocket's first stage burn to trace the bright orange arc and a 30 second exposure at high sensitivity...

Explanation: A waning crescent moon, early morning twilight, and Al Hamra's city lights on the horizon can't hide the central Milky Way in this skyscape from planet Earth. Captured in a single exposure, the dreamlike scene looks southward across the region's grand canyon from Jabal Shams (Sun Mountain), near the highest peak in Oman, on the Arabian Peninsula. Mist, moonlight, and shadows still play along the steep canyon walls. Dark rifts along the luminous band of the Milky Way are the galaxy's cosmic dust clouds. Typically hundreds of light-years distant, they obscure starlight along the galactic plane, viewed edge-on from...

The galaxy’s empire has a new colony. Astronomers have detected a dwarf galaxy orbiting the Milky Way whose span stretches farther than nearly all other Milky Way satellites. It may belong to a small group of galaxies that is falling into our own. Giant galaxies like the Milky Way grew large when smaller galaxies merged, according to simulations. The simulations also suggest that whole groups of galaxies can fall into a single giant at the same time. The best examples in our cosmic neighbourhood are the Large and Small Magellanic Clouds, the Milky Way’s two brightest satellites, which probably orbit...

Mysterious high-energy particles known as cosmic rays zip through space at a wide range of energies, some millions of times greater than those produced in the world’s most powerful atom smasher. Scientists have long thought cosmic rays from inside our galaxy come from supernova explosions, but a new study has fingered a second source: the supermassive black hole at the heart of the Milky Way. With this new result, the search for cosmic ray origins, which has frustrated scientists for more than 100 years, has taken an unexpected new twist. “It’s very exciting,” says astrophysicist Andrew Taylor of the Dublin...

Scientists have made a cosmic growth chart of the Milky Way galaxy, an innovative blending of data collected by the ongoing Sloan Digital Sky Survey and a new technique to determine the ages of stars. As expected, the analysis shows the galaxy’s central disk formed from the inside out, with red giant stars as old as about 13 billion years clustered toward the center and younger stars about 1 billion years old closer to the disk’s edge, astronomer Melissa Ness, with the Max Planck Institute for Astronomy in Heidelberg, Germany, told reporters at the American Astronomical Society meeting in Kissimmee,...

An Australian telescope used to broadcast live vision of man's first steps on the moon in 1969 has found hundreds of new galaxies hidden behind the Milky Way by using an innovative receiver that measures radio waves. Scientists at the Parkes telescope, 355 km (220 miles) west of Sydney, said they had detected 883 galaxies, a third of which had never been seen before. The findings were reported in the latest issue of Astronomical Journal under the title 'The Parkes HI Zone of Avoidance Survey'. "Hundreds of new galaxies were discovered, using the same telescope that was used to broadcast...

Hundreds of hidden nearby galaxies have been studied for the first time, shedding light on a mysterious gravitational anomaly dubbed the Great Attractor. Despite being just 250 million light years from Earth—very close in astronomical terms—the new galaxies had been hidden from view until now by our own galaxy, the Milky Way. Using CSIRO’s Parkes radio telescope equipped with an innovative receiver, an international team of scientists were able to see through the stars and dust of the Milky Way, into a previously unexplored region of space. The discovery may help to explain the Great Attractor region, which appears to...

Explanation: The Big Dipper is an easy to recognize, well-known asterism in northern skies, though many see the Plough or Wagon. Famous bright nebulae of the north can also be found along its familiar lines, highlighted in this carefully composed scene with telescopic insets framed in the wider-field skyview. All from Messier's catalog, M101 and M51 are cosmic pinwheel and whirlpool on the left, spiral galaxies far beyond the Milky Way. To the right, M108, a distant edge-on spiral galaxy is seen close to our galaxy's own owl-faced planetary nebula M97. Taken on January 16, the wider-field view seems to...

It's a common theme in science fiction, but migrating to planets beyond our solar system will be a lot more complicated and difficult than you might imagineThe idea that humans will eventually travel to and inhabit other parts of our galaxy was well expressed by the early Russian rocket scientist Konstantin Tsiolkovsky, who wrote, “Earth is humanity’s cradle, but you’re not meant to stay in your cradle forever.” Since then the idea has been a staple of science fiction, and thus become part of a consensus image of humanity’s future. Going to the stars is often regarded as humanity’s destiny,...

Explanation: The Henbury craters in the Northern Territory, Australia, planet Earth, are the scars of an impact over 4,000 years old. When an ancient meteorite fragmented into dozens of pieces, the largest made the 180 meter diameter crater whose weathered walls and floor are lit in the foreground of this southern hemisphere nightscape. The vertical panoramic view follows our magnificent Milky Way galaxy stretching above horizon, its rich central starfields cut by obscuring dust clouds. A glance along the galactic plane also reveals Alpha and Beta Centauri and the stars of the Southern Cross. Captured in the region's spectacular, dark...

Explanation: Earth's annual Geminid meteor shower did not disappoint, peaking before dawn on December 14 as our fair planet plowed through dust from active asteroid 3200 Phaethon. Captured in this southern hemisphere nightscape the meteors stream away from the shower's radiant in Gemini. To create the image, many individual frames recording meteor streaks were taken over period of 5 hours. In the final composite they were selected and registered against the starry sky above the twin 6.5 meter Magellan telescopes of Carnegie Las Campanas Observatory in Chile. Rigel in Orion, and Sirius shine brightly as the Milky Way stretches toward...