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A pulsar with its jets and magnetic fields (NASA) ====================================================================== Far out in the Milky Way, roughly 22,000 light years from Earth, a star unlike any other roars with a magnetic force that beats anything physicists have ever seen. At a whopping 1.6 billion Tesla, a pulsar called Swift J0243.6+6124 smashes the previous records of around 1 billion Tesla, discovered surrounding the pulsars GRO J1008-57 and 1A 0535+262. For a bit of context, your average novelty fridge magnet comes in at around 0.001 Tesla. The more powerful MRI machines manage to hit around 3 Tesla. A few years ago, engineers...

The MWA's view of the sky; the object is marked with a white star. (Dr Natasha Hurley-Walker/ICRAR/Curtin and the GLEAM Team) Something in Earth's cosmic neighborhood is emitting weird signals of a kind we've never seen before. Just 4,000 light-years away, something is flashing radio waves. For roughly 30 to 60 seconds, every 18.18 minutes, it pulses brightly, one of the most luminous objects in the low-frequency radio sky. It matches the profile of no known astronomical object, and astronomers are gobsmacked. They have named it GLEAM-X J162759.5-523504.3. "This object was appearing and disappearing over a few hours during our...

Illustration of the double pulsar PSR J0737−3039A/B. (Michael Kramer/MPIfRA) Two pulsars locked in close binary orbit have once again validated predictions made by Einstein's theory of general relativity. Over 16 years, an international team of astronomers has observed the pulsar pair, named PSR J0737−3039A/B, finding that the relativistic effects can be measured in the timing of their pulses – just as predicted and expected. This is the first time these effects have been observed. "We studied a system of compact stars that is an unrivalled laboratory to test gravity theories in the presence of very strong gravitational fields," says astronomer...

An amazing new Nasa image captures the youngest pulsar ever found by scientists. The pulsar - an ultra-dense chunk of a star leftover from its explosive death into a supernova - sits just 19,000 light years from Earth. It provides our best look yet at the early stages of star death, a mysterious and violent process that scientists still don't fully understand. The image was taken using Nasa's Chandra X-ray Observatory, an orbiting telescope that has been out of action for nearly two weeks following a catastrophic gyroscope failure.

As Snyder-Beattie explained in the article, the “Great Filter” is a response to the question of why we can’t see any alien civilizations. The “Great Filter” deals with similar issues as the Drake Equation, which talks about the probability of communicating civilizations outside of Earth, and the Fermi Paradox, which asks where the civilizations are. Simply speaking, the idea is that if a civilization continues to expand (especially at the technological pace we humans have experienced), it wouldn’t take all that long in the lifespan of the universe for artificial processes to be visible with our own telescopes. Yes, this...

~snip~ In 1967 British astronomer Jocelyn Bell Burnell was left stunned by mysterious pulsing signals she detected coming from outside the solar system. For months she suggested the signals could be of an extraterrestrial intelligent origin, but they were later proven to be rapidly spinning stars known as pulsars. However, a new series of mysterious signals, known as Fast Radio Bursts (FRBs), has again got astronomers scratching their heads and wondering if, maybe, we’re picking up alien messages...

September 14, 2006 - An international research team led by Prof. Michael Kramer of the University of Manchester’s Jodrell Bank Observatory, UK, has used three years of observations of the “double pulsar”, a unique pair of natural stellar clocks which they discovered in 2003, to prove that Einstein’s theory of general relativity–the theory of gravity that displaced Newton’s–is correct to within a staggering 0.05%. Their results are published on the14th September in the journal Science and are based on measurements of an effect called the Shapiro Delay. The double pulsar system, PSR J0737-3039A and B, is 2000 light-years away in...

Okay, but what exactly is a gravitational wave and how could they help us crack the conundrum of the black hole code? A gravitational wave is akin to a ripple in space-time. Albert Einstein predicted that massive bodies changing speed or direction generate these gravitational waves. Picture bodies like a pair of black holes orbiting each other. This then creates a gravitational wave that ripples outwards, like a disturbance in a still pool of water after a leaf has dropped onto its surface and ripples are sent across the surface. Like star-crossed lovers, the black holes of two merging galaxies...

In today’s issue of Science, CSIRO astronomer George Hobbs and colleagues in the UK, Germany and Canada report that they have taken a big step towards solving a 30-year-old puzzle: why the “cosmic clocks” called pulsars aren’t perfect.“We now have a more fundamental understanding of how pulsars work,” Dr Hobbs said. “We’ve shown that many pulsar characteristics are linked, because they have one underlying cause.” Armed with this understanding, astronomers will find it easier to compensate for errors in their pulsar “clocks” when they use them as tools - for instance, in trying to detect gravitational waves, which is something...

WASHINGTON (Reuters) - Reckless pulsars -- spinning searchlights in space -- might tear themselves apart if they whirled too fast, but ripples in the cosmic fabric first predicted by Albert Einstein may set a celestial speed limit. That limit is still extremely high, about 760 revolutions per second, astronomers said on Wednesday. But scientists figure some of the fastest pulsars could technically go two or three times that speed. Unfortunately, they would inevitably disintegrate if they did. What stops them is the phenomenon predicted by Einstein's theory of relativity -- the rippling of the fabric of space and time. Known...

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2002 March 11 The 100-Meter Green Bank Radio Telescope Credit: NRAO, NSF Explanation: The largest single-dish fully steerable radio telescope began operation in 2000 August in Green Bank, West Virginia, USA. Dedicated as the Robert C. Byrd Green Bank Telescope, the device weighs over 30 times more than the Statue of Liberty, and yet can point anywhere in the sky more precisely than one thousandth of a degree....