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Explanation: What's causing a huge jet to emanate from the center of galaxy M87? Although the unusual jet was first noticed early in the twentieth century, the exact cause is still debated. The above picture taken by the Hubble Space Telescope in 1998 shows clear details, however. The most popular hypothesis holds that the jet is created by energetic gas swirling around a massive black hole at the galaxy's center. The result is a 5000 light-year long blowtorch where electrons are ejected outward at near light-speed, emitting eerily blue light during a magnetic spiral. M87 is a giant elliptical galaxy...

Astronomers have discovered the largest and oldest mass of water ever detected in the universe — a gigantic, 12-billion-year-old cloud harboring 140 trillion times more water than all of Earth's oceans combined. The cloud of water vapor surrounds a supermassive black hole called a quasar located 12 billion light-years from Earth. The discovery shows that water has been prevalent in the universe for nearly its entire existence, researchers said. "Because the light we are seeing left this quasar more than 12 billion years ago, we are seeing water that was present only some 1.6 billion years after the beginning of...

The most distant objects in the universe are also the oldest -- or at least that is how they appear to us, because their light has had to travel for billions of years to get here. They are also extraordinarily faint since they are so far away, and only in the last decade have astronomers been able to stretch their vision using the newest telescopes and clever techniques. One such innovation occurred with the launch of the NASA Swift satellite in 2004; it searches for bursts of gamma-ray emission, called GRBs. These flashes, thought to result from the especially spectacular...

Explanation: Peculiar spiral galaxy Arp 78 is found within the boundaries of the head strong constellation Aries, some 100 million light-years beyond the stars and nebulae of our Milky Way galaxy. Also known as NGC 772, the island universe is over 100 thousand light-years across and sports a single prominent outer spiral arm in this detailed cosmic portrait. Its brightest companion galaxy, compact NGC 770, is toward the upper right of the larger spiral. NGC 770's fuzzy, elliptical appearance contrasts nicely with a spiky foreground Milky Way star in matching yellowish hues. Tracking along sweeping dust lanes and lined with...

30 June 2011 ESA’s Integral gamma-ray observatory has provided results that will dramatically affect the search for physics beyond Einstein. It has shown that any underlying quantum ‘graininess’ of space must be at much smaller scales than previously predicted. Einstein’s General Theory of Relativity describes the properties of gravity and assumes that space is a smooth, continuous fabric. Yet quantum theory suggests that space should be grainy at the smallest scales, like sand on a beach. One of the great concerns of modern physics is to marry these two concepts into a single theory of quantum gravity. Now, Integral has...

Explanation: What does the universe nearby look like? This plot shows nearly 50,000 galaxies in the nearby universe detected by the Two Micron All Sky Survey (2MASS) in infrared light. The resulting image is anincredible tapestry of galaxies that provides limits on how the universe formed and evolved. The dark band across the image center is blocked by dust in the plane of our own Milky Way Galaxy. Away from the Galactic plane, however, each dot represents a galaxy, color coded to indicate distance. Bluer dots represent the nearer galaxies in the 2MASS survey, while redder dots indicating the more...

Called blue stragglers, these cannibal stars have been spotted in other parts of the Milky Way. They seem to lag in age next to the other stars with which they formed—appearing hotter, and thus younger and bluer. Astronomers suspect blue stragglers look so youthful because they've stolen hydrogen fuel from other stars, perhaps after colliding into their victims. These cannibal stars are routinely found in dense star clusters, where stars have many chances to feed off each other. Now, however, scientists have found blue stragglers in the Milky Way's galactic bulge, a dense region of stars and gas surrounding the...

Astronomers using the Hubble Space Telescope have peered further back in time than ever before, spotting a galaxy that formed less than 500 million years after the birth of our universe, making it the oldest and most distant ever seen. The find, reported today (Jan. 26) in the journal Nature, should help astronomers better understand the early days of the universe, researchers said. In particular, the discovery should shed light on the evolution of early galaxies, which first formed just a few hundred million years after the Big Bang."In essence, the most important aspect of this is, it provides us...

‘Blue Stragglers’ in the Galactic Bulge by Paul Gilster on May 30, 2011 I’m fascinated by how much the exoplanet hunt is telling us about celestial objects other than planets. The other day we looked at some of the stellar spinoffs from the Kepler mission, including the unusual pulsations of the star HD 187091, now known to be not one star but two. But the examples run well beyond Kepler. Back in 2006, a survey called the Sagittarius Window Eclipsing Extrasolar Planet Search (SWEEPS) used Hubble data to study 180,000 stars in the galaxy’s central bulge, the object being...

[Composite Image Credit & Copyright: Dennis L. Mammana (TWAN)] Explanation: If you're driving down a dark road on a starry night, you might want to check the odometer. Earlier this month, when traveling astronomer Dennis Mammana did he was greeted with the significant mileage reading of 186,282 miles. That's the number of miles light travels in one second. Or, if you prefer kilometers, the number you are looking for is 299,792. Mammana muses that in driving to countless observatories, star parties, and night sky photo shoots it has taken his 1998 vintage sport utility vehicle over 13 years to cover...

A gamma-ray burst detected by NASA's Swift satellite in April 2009 has been newly unveiled as a candidate for the most distant object in the universe. At an estimated distance of 13.14 billion light years, the burst lies far beyond any known quasar and could be more distant than any previously known galaxy or gamma-ray burst. Multiple lines of evidence in favor of a record-breaking distance for this burst, known as GRB 090429B for the 29 April 2009 date when it was discovered, are presented in a paper by an international team of astronomers led by former Penn State University...

NASA's Hubble Space Telescope has been trained on a single variable star that in 1923 altered the course of modern astronomy. V1 is a special class of pulsating star called a Cepheid variable that can be used to make reliable measurements of large cosmic distances. Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)

CORVALLIS, Ore. – Whether they know it or not, anyone who's ever gotten a speeding ticket after zooming by a radar gun has experienced the Doppler effect – a measurable shift in the frequency of radiation based on the motion of an object, which in this case is your car doing 45 miles an hour in a 30-mph zone. But for the first time, scientists have experimentally shown a different version of the Doppler effect at a much, much smaller level – the rotation of an individual molecule. Prior to this such an effect had been theorized, but it took...

Enlarge Image Breathing fire. A distant cosmic explosion detected 28 March (left) continues to put out a series of high-energy flares (right). Astronomers believe it's a star being consumed by a black hole 3.8 billion light-years away. Credit: (left, galaxy) ASA/Swift/Stefan Immler; (right, diagram) NASA/Swift/Penn State/J. Kennea Astronomers have observed possibly the biggest blast ever seen in the cosmos. When NASA's SWIFT space observatory first spotted it 10 days ago, observers thought it was a massive star blowing up as a supernova and expected it to fade within hours or even minutes. But the high-energy radiation from the source...

Astronomers have found distant red galaxies—very massive and very old—in the universe when it was only 2.5 billion years post Big Bang. “Previous observations suggested that the universe at this age was home to young, small clumps of galaxies long before they merged into massive structures we see today,” remarked Carnegie Observatories Ivo Labbé, who led the group of astronomers in the study. [Members of the research project are listed at the end of the original article.] “We are really amazed — these are the earliest, oldest galaxies found to date. Their existence was not predicted by theory and it...

A hundred million years ago, a triple-star system was traveling through the bustling center of our Milky Way galaxy when it made a life-changing misstep. The trio wandered too close to the galaxy's giant black hole, which captured one of the stars and hurled the other two out of the Milky Way. Adding to the stellar game of musical chairs, the two outbound stars merged to form a super-hot, blue star. This story may seem like science fiction, but astronomers using NASA's Hubble Space Telescope say it is the most likely scenario for a so-called hypervelocity star, known as HE...

The Double Quasar image bodes well for the UK's future in radio astronomy E-Merlin is an array of seven linked UK radio telescopes, updated last year with fibre optic technology that has vastly increased its power. Light from the Double Quasar has been bent by a massive object between it and the Earth, resulting in a double image.This gravitational lensing is a powerful demonstration of one aspect of Einstein's theory of relativity.The quasar - short for quasi-stellar radio source - sprays out tremendous amounts of energy and matter, powered by a super-massive black hole at its heart.The E-Merlin image shows...

Have we found the universe that existed before the Big Bang? The current cosmological consensus is that the universe began 13.7 billion years ago with the Big Bang. But a legendary physicist says he's found the first evidence of an eternal, cyclic cosmos. The Big Bang model holds that everything that now comprises the universe was once concentrated in a single point of near-infinite density. Before this singularity exploded and the universe began, there was absolutely nothing - indeed, it's not clear whether one can even use the term "before" in reference to a pre-Big-Bang cosmos, as time itself may...

For the first time, scientists believe they have witnessed the birth of a black hole. This Story Scientists witness the apparent birth of a black hole Animation: Supernova producing a black hole Interactive map of nearby black hole The evidence began arriving 30 years ago from a star 50 million light-years away that had imploded, setting into motion events that created a region where gravity is so great that nothing can escape, even light. The initial 1979 observation of the exploding star was made by an amateur astronomer from Western Maryland, but the profession's top scientists have studied it intently...

Allan R. Sandage, who spent his life measuring the universe, becoming the most influential astronomer of his generation, died Saturday at his home in San Gabriel, Calif. He was 84. The cause was pancreatic cancer, according to an announcement by the Carnegie Observatories, where he had spent his whole professional career. Over more than six decades, Dr. Sandage was like one of those giant galaxies that sit at the center of a cluster of galaxies, dominating cosmic weather. He wrote more than 500 papers, ranging across the cosmos, covering the evolution and behavior of stars, the birth of the Milky...