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Explanation: In 185 AD, Chinese astronomers recorded the appearance of a new star in the Nanmen asterism. That part of the sky is identified with Alpha and Beta Centauri on modern star charts. The new star was visible to the naked-eye for months, and is now thought to be the earliest recorded supernova. This deep telescopic view reveals the wispy outlines of emission nebula RCW 86, just visible against the starry background, understood to be the remnant of that stellar explosion. Captured by the wide-field Dark Energy Camera operating at Cerro Tololo Inter-American Observatory in Chile, the image traces the...

An orbiting star begins to eclipse its partner, a rapidly rotating, superdense stellar remnant called a pulsar. Image courtesy of Aurore Simonnet/Sonoma State University/NASA *************************************************************************** Jan. 26 (UPI) -- NASA made a first-of-its-kind discovery with its Fermi Gamma-ray Space Telescope, spotting the first gamma-ray eclipses from a special type of star system. The agency shared the news with Nature Astronomy on Thursday after scientists researched a decade of observations from the telescope that can detect the most astonishing celestial events from gamma bursts to black holes. Gamma-ray eclipses were observed from a special binary star system that is orbited by...

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...

Explanation: The Crab Nebula is cataloged as M1, the first object on Charles Messier's famous list of things which are not comets. In fact, the Crab is now known to be a supernova remnant, expanding debris from massive star's death explosion, witnessed on planet Earth in 1054 AD. This brave new image offers a 21st century view of the Crab Nebula by presenting image data from across the electromagnetic spectrum as wavelengths of visible light. From space, Chandra (X-ray) XMM-Newton (ultraviolet), Hubble (visible), and Spitzer (infrared), data are in purple, blue, green, and yellow hues. From the ground, Very Large...

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...

For more than two decades, astronomers have been systematically tracing mystery sources of high-energy gamma rays to their sources. One, however, remained stubborn - the brightest unidentified source of gamma rays in the Milky Way. It seemed to be coming from a binary system 2,740 light-years away, but only one of the stars could be found. Now, astronomers have solved the mystery and pinned down that second star by searching gamma-ray data obtained between 2008 and 2018. Together, the two stars constitute one of the weirdest binary systems we've ever seen. "The binary star system and the neutron star at...

A newly examined ice core shows what may be the chemical traces of supernovae that exploded a thousand years ago. Yuko Motizuki of the RIKEN research institute in Wako, Japan, and colleagues analysed the nitrate content of an ice core drilled at Dome Fuji station in Antarctica. Nitrate is produced in the atmosphere by nitrogen oxides, which in turn should be created by the gamma radiation from a supernova. Motizuki's group found high nitrate concentrations in three thin layers about 50 metres deep. Because snow gradually builds up into layers of ice, depth indicates age. After calibrating this icy calendar...

Observations of a trio of dead stars have confirmed that a foundation of Einstein’s gravitational theory holds even for ultradense objects with strong gravitational fields. The complex orbital dance of the three former stars conforms to a rule known as the strong equivalence principle, researchers reported January 10 at a meeting of the American Astronomical Society. That agreement limits theories that predict Einstein’s theory, general relativity, should fail at some level. According to general relativity, an object’s composition has no impact on how gravity pulls on it: Earth’s gravity accelerates a sphere of iron at the same rate as a...

The recent finding, detailed in the journal Science today (Nov. 17), concerns positrons, the antimatter complements of electrons. High-energy particles, usually protons, traveling across the galaxy can create pairs of positrons and electrons when they interact with dust and gas in space, study co-author Hao Zhou, at Los Alamos National Lab, told Space.com. In 2008, the space-based PAMELA detector measured unexpectedly high numbers of earthbound positrons. This was about 10 times what they were expecting to see, according to Zhou. ... Zhou's team made detailed measurements of the gamma-rays coming from the direction of two nearby pulsars — Geminga and its companion...

A pulsar, one of deep space’s spinning “lighthouses”, has faded from view because a warp in space-time tilted its beams away from Earth. The tiny, heavy pulsar is locked in a fiercely tight orbit with another star. The gravity between them is so extreme that it is thought to emit waves and to bend space - making the pulsar wobble. By tracking its motion closely for five years, astronomers determined the pulsar’s weight and also quantified the gravitational disturbance. Then, the pulsar vanished. Its wheeling beams of radio waves now pass us by, and the researchers have calculated that this...

Explanation: The Lighthouse nebula was formed by the wind of a pulsar, a rapidly rotating, magnetized neutron star, as it speeds through the interstellar medium at over 1,000 kilometers per second. Some 23,000 light-years distant toward the southern constellation Carina, pulsar and wind nebula (cataloged as IGR J1104-6103) are indicated at the lower right in this remarkable image from the Chandra X-ray Observatory. Energetic particles generated by the pulsar are swept back into the wind's comet-like tail trailing up and to the left, along the direction of the pulsar's motion away from its parent supernova remnant. Both runaway pulsar and...

Data from several different space and ground based observatories imply the presence of a nearby object that is beaming cosmic rays our way. Scientists with the Fermi Space Telescope say an unknown pulsar may be close by, sending electrons and positrons towards Earth. Or another more exotic explanation is that the particles could come from the annihilation of dark matter. But whatever it is, the source is relatively close, surely in our galaxy. “If these particles were emitted far away, they’d have lost a lot of their energy by the time they reached us,” said Luca Baldini, a Fermi collaborator....

WASHINGTON (Reuters) - Astronomers are baffled after finding an exotic type of star called a pulsar apparently locked in an elongated orbit around a star much like the sun -- an arrangement defying what had been known about such objects. The rapidly spinning pulsar -- an extraordinarily dense object created when a massive star exploded as a supernova -- is called J1903+0327 and is located about 21,000 light years from Earth, the astronomers said. A light year is about 6 trillion miles, the distance light travels in a year. "The big question is -- how in the heck did this...

Enlarge ImageGrowing pains. This artist's conception shows a neutron star known as a magnetar crackling with extremely powerful magnetic activity.Credit: Gregg Dinderman/Sky & Telescope "When you hear hoofbeats," the old saying goes, "think horse, not zebra." But what if your horse suddenly grows zebra stripes? That's the predicament astronomers faced when a star they were observing--a rapidly spinning remnant of a supernova called a pulsar--started emitting powerful bursts of x-rays considered the hallmark of a much-rarer object called a magnetar. The finding strongly suggests that pulsars, also known as neutron stars, and magnetars are linked and paves the way...

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...

Using data from ESA's XMM-Newton X-ray observatory, an international group of astrophysicists has discovered a spinning neutron star that seems to be tumbling slowly - a find that could provide new insight into the evolution and structure of these super-dense objects. Spinning neutron stars, also known as pulsars, generally rotate on highly stable axes. Thanks to their periodic signals, emitted either in radio or X-ray wavelengths, they can serve as very accurate astronomical clocks. Regarding pulsar RX J0720.4-3125, however, the team found that over the past four and a half years, its temperature has been rising - until very recently,...

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. 2004 January 28 The Crab Nebula from CFHT Credit & Copyright: Canada-France-Hawaii Telescope, J.-C. Cuillandre (CFHT), Coelum Explanation: 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...

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. 2003 September 14 The Crab Nebula from VLT Credit: FORS Team, 8.2-meter VLT, ESO Explanation: The Crab Nebula, filled with mysterious filaments, is the result of a star that was seen to explode in 1054 AD. This spectacular supernova explosion was recorded by Chinese and (quite probably) Anasazi Indian astronomers. The filaments are mysterious because they appear to have less mass than expelled in the original supernova and...

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. 2003 September 4 Composite Crab Credit: J. Hester (ASU) et al., CXC, HST, NASA Explanation: The Crab Pulsar, a city-sized, magnetized neutron star spinning 30 times a second, lies at the center of this composite image of the inner region of the well-known Crab Nebula. The spectacular picture combines optical data (red) from the Hubble Space Telescope and x-ray images (blue) from the Chandra Observatory, also used in...

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. 2003 July 18 The Planet, the White Dwarf, and the Neutron StarCredit: H. Richer (Univ. British Columbia), et al. NASA, NOAO Explanation: A planet, a white dwarf, and a neutron star orbit each other in the giant globular star cluster M4, some 5,600 light-years away. The most visible member of the trio is the white dwarf star, indicated above in an image from the Hubble Space Telescope, while...