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Combination of a Hubble Space Telescope image of SN 1987A and the compact argon source. The faint blue source in the centre is the emission from the compact source detected with the JWST/NIRSpec instrument. Outside this is the stellar debris, containing most of the mass, expanding at thousands of km/second. The inner bright "string of pearls" is the gas from the outer layers of the star that was expelled about 20,000 years before the final explosion. The is the fast debris are now colliding with the ring, explaining the bright spots. Outside of the inner ring are two outer rings,...

Artist’s impression of GRB 211211A. Scientists have linked this unusual gamma-ray burst from a nearby galaxy to a neutron star merger. Credit: Soheb Mandhai @TheAstroPhoenix An unusually powerful gamma-ray burst (GRB 211211A), detected from a nearby galaxy, has been linked to a neutron star merger by an international team of scientists. This burst, notable for its excess of infrared light, was shown to originate from a kilonova, an event thought to occur when neutron stars collide. Scientists have linked a highly unusual blast of high-energy light from a nearby galaxy to a neutron star merger. The event, detected in December...

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...

What Happens If A Star Explodes Near The Earth?Veritasium | November 15, 2022

The object, named FRB 20201124A, was detected with the Five-hundred-meter Aperture Spherical radio Telescope (FAST) in China and described in a new paper led by astronomer Heng Xu of Peking University in China. So far most evidence points to a magnetar – a neutron star with extraordinarily strong magnetic fields – as a source of FRB emissions like this. If FRB 20201124A is indeed from one of these wild cosmic beasts, it's looking like an unusual specimen. Polarization refers to the orientation of light waves in three-dimensional space. By examining how much that orientation has changed since the light departed...

An illustration depicting GRB21106A. The event itself is seen as a white jet in the center of the frame, stemming from the merger seen as a pale blue lighted disk on the bottom left, and the shockwave afterglow is seen as a larger, semi-circular lit-up region toward the middle right. This artist's conception shows the merger between a neutron star and another star (disk, lower left) which caused an explosion resulting in GRB 211106A (white jet, middle), and left behind one of the most luminous afterglows on record (semispherical shock wave midright). ALMA (ESO/NAOJ/NRAO), M. Weiss (NRAO/AUI/NSF) ************************************************************************************** Astronomers presented...

Almost seven years ago (September 14th, 2015), researchers at the Laser Interferometer Gravitational-wave Observatory (LIGO) detected gravitational waves (GWs) for the first time. Their results were shared with the world six months later and earned the discovery team the Noble Prize in Physics the following year. Since then, a total of 90 signals have been observed that were created by binary systems of two black holes, two neutron stars, or one of each. This latter scenario presents some very interesting opportunities for astronomers. If a merger involves a black hole and neutron star, the event will produce GWs and a...

Artist’s impression of a neutron star-black hole merger event. (Carl Knox/OzGrav/Swinburne University) For the first time, scientists have unambiguously confirmed the collision of a black hole and a neutron star: The fateful moment two extreme objects come together in an event so immensely powerful, its ripples across the cosmos can still be discerned a billion years later. Amazingly enough, this astronomical discovery has now been made not once, but twice, as an international collaboration of thousands of scientists reports. In a new study confirming this world-first observation, researchers detail the detection of gravitational waves resulting from two separate and distinct...

A satellite experiment has revealed that the heaviest known neutron star is unexpectedly large, which suggests that the matter in the star’s inner core is less “squeezable” than some models predict. NICER measures the size of a neutron star by tracking the x-ray emission from “hot spots” on the surface as the star rotates. These spots occur at the magnetic poles of the star, where the field slams particles onto the star surface. Neutron stars are “cosmic zombies”­—corpses of massive stars that collapsed in violent explosions after running out of fuel. By studying these ultradense objects, researchers hope to understand...

Explanation: Over fifty gravitational wave events have now been detected. These events mark the distant, violent collisions of two black holes, a black hole and a neutron star, or two neutron stars. Most of the 50 events were detected in 2019 by the LIGO gravitational wave detectors in the USA and the VIRGO detector in Europe. In the featured illustration summarizing the masses of the first 50 events, blue dots indicate higher-mass black holes while orange dots denote lower-mass neutron stars. Astrophysicists are currently uncertain, though, about the nature of events marked in white involving masses that appear to be...

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...

When humanity finally detected the collision between two neutron stars in 2017, we confirmed a long-held theory - in the energetic fires of these incredible explosions, elements heavier than iron are forged. And so, we thought we had an answer to the question of how these elements - including gold - propagated throughout the Universe. But a new analysis has revealed a problem. According to new galactic chemical evolution models, neutron star collisions don't even come close to producing the abundances of heavy elements found in the Milky Way galaxy today. "Neutron star mergers did not produce enough heavy elements...

Gold is an element, which means you can't make it through ordinary chemical reactions — though alchemists tried for centuries. To make the sparkly metal, you have to bind 79 protons and 118 neutrons together to form a single atomic nucleus. That's an intense nuclear fusion reaction. But such intense fusion doesn't happen frequently enough, at least not nearby, to make the giant trove of gold we find on Earth and elsewhere in the solar system. And a new study has found the most commonly-theorized origin of gold — collisions between neutron stars — can't explain gold's abundance either. So...

The so-called Fast Radio Burst repeats every 157 days with the power of millions of suns and its latest barrage arrived right on time last week. Known as FRB 121102, scientists hope that studying the strange blinkering signal could unlock the secret to what FRBs are and where they come from. Fast Radio Bursts are intense pulses of radio waves that last no longer than the blink of an eye and come from far beyond our Milky Way galaxy. Their origins are unknown. . The group’s findings, to The Astronomer’s Telegram, suggest the burst is currently in its active phase...

Most FRBs originate hundreds of millions of light-years away. This one came from inside the Milky Way. Thirty thousand years ago, a dead star on the other side of the Milky Way belched out a powerful mixture of radio and X-ray energy. On April 28, 2020, that belch swept over Earth, triggering alarms at observatories around the world. The signal was there and gone in half a second, but that's all scientists needed to confirm they had detected something remarkable: the first ever "fast radio burst" (FRB) to emanate from a known star within the Milky Way, according to a...

On Aug. 14, 2019, a gravitational wave -- a massive ripple through the fabric of space-time -- washed over the Earth. The signal was one of the strongest ever seen by the gravitational wave scientists at the Laser Interferometer Gravitational-wave Observatory and Italy's Virgo observatory. After an alert was sent out moments after detection, teams of astronomers across the world turned their telescopes to the point in space that the wave emanated from. But their searches came up empty. No light, no X-rays, no infrared, no gamma rays. On Tuesday, researchers from the LIGO and Virgo collaborations detail their full...

Our magnificent gravitational wave astronomers have done it again, adding to the detection collection a new collision between two neutron stars. On 25 April 2019, the LIGO interferometer detected two neutron stars around 520 million light-years away coming together and merging into a single object. It's called GW190425, and although it's only the second such collision astronomers have ever seen, it's already broadening our understanding of these colossal cosmic smash-ups.

Enough gold, uranium and other heavy elements about equal in mass to all of Earth's oceans likely came to the solar system from the collision of two neutron stars billions of years ago, a new study finds. If the same event were to happen today, the light from the explosion would outshine the entire night sky, and potentially prove disastrous for life on Earth, according to the new study's researchers. Recent findings have suggested that much of the gold and other elements heavier than iron on the periodic table was born in the catastrophic aftermath of colliding neutron stars,...

Stars the mass of our Sun, and up to eight times more massive, evolve into red giants towards the end of their lives. Their outer layers puff up and expand millions of kilometres, their dusty, gassy shells blown away from the central star in relatively slow winds up to few hundreds of km/s. Even larger stars, up to 25–30 times more massive than the Sun, race through their fuel and explode in a supernova, sometimes leaving behind a spinning stellar corpse with a strong magnetic field, known as a neutron star. This tiny core packs the mass of nearly one...

Explanation: At the core of the Crab Nebula lies a city-sized, magnetized neutron star spinning 30 times a second. Known as the Crab Pulsar, it's actually the rightmost of two bright stars, just below a central swirl in this stunning Hubble snapshot of the nebula's core. Some three light-years across, the spectacular picture frames the glowing gas, cavities and swirling filaments bathed in an eerie blue light. The blue glow is visible radiation given off by electrons spiraling in a strong magnetic field at nearly the speed of light. Like a cosmic dynamo the pulsar powers the emission from the...