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An invisible force is having an effect on our Universe. We can't see it, and we can't detect it - but we can observe how it interacts gravitationally with the things we can see and detect, such as light. Now an international team of astronomers has used one of the world's most powerful telescopes to analyse that effect across 10 million galaxies in the context of Einstein's general relativity. The result? The most comprehensive map of dark matter across the history of the Universe to date. ... "If further data shows we're definitely right, then it suggests something is missing...

Late in 2018, the gravitational wave observatory, LIGO, announced that they had detected the most distant and massive source of ripples of spacetime ever monitored: waves triggered by pairs of black holes colliding in deep space. Only since 2015 have we been able to observe these invisible astronomical bodies, which can be detected only by their gravitational attraction. The history of our hunt for these enigmatic objects traces back to the 18th century, but the crucial phase took place in a suitably dark period of human history – World War II. The concept of a body that would trap light,...

Black holes are among the most mysterious places in the universe; locations where the very fabric of space and time are warped so badly that not even light can escape from them. According to Einstein's theory of general relativity, at their center lies a singularity, a place where the mass of many stars is crushed into a volume with exactly zero size. However, two recent physics papers, published on Dec.10 in the journals Physical Review Letters and Physical Review D, respectively, may make scientists reconsider what we think we know about black holes. Black holes might not last forever, and...

Scientists at the University of Oxford may have solved one of the biggest questions in modern physics, with a new paper unifying dark matter and dark energy into a single phenomenon: a fluid which possesses 'negative mass." If you were to push a negative mass, it would accelerate towards you. This astonishing new theory may also prove right a prediction that Einstein made 100 years ago. Our current, widely recognised model of the Universe, called LambdaCDM, tells us nothing about what dark matter and dark energy are like physically. We only know about them because of the gravitational effects they...

Broderick's work builds on earlier research by two teams that studied the galactic center of the Milky Way in near-infrared. This included the work of Reinhard Genzel, an astronomer from the Max Planck Institute for Extraterrestrial Physics in Garching, Germany, as well as researchers Andrea Ghez and Mark Morris of University of California, Los Angeles. At the time, their work revealed that the center of the Milky Way wasn't steady, but instead would drastically brighten about once a day for about 30 or 40 minutes, Broderick said. Researchers think supermassive black holes exist at the center of most, if not...

Circling our galaxy is a stealthy giant. Astronomers have discovered a dwarf galaxy, called Antlia 2, that is one-third the size of the Milky Way itself. As big as the Large Magellanic Cloud, the galaxy’s largest companion, Antlia 2 eluded detection until now because it is 10,000 times fainter. Such a strange beast challenges models of galaxy formation and dark matter, the unseen stuff that helps pull galaxies together. “It’s a very odd object and kind of exciting because we don’t know yet how to interpret all of its properties,” says Andrey Kravtsov of The University of Chicago in Illinois,...

Dust clouds that orbit Earth like moons may finally have had their existence confirmed after more than a half-century of controversy, new research finds. In deep space, there are five points where the gravitational pull of Earth and the moon balance each other. Two of these so-called Lagrange points, L4 and L5, form an equal-sided triangle with Earth and the moon, and move around Earth as the moon orbits the planet. Any objects at either L4 or L5 can stay in relatively stable positions there about 239,000 miles (384,000 kilometers) from both Earth and the moon, barring any interference from...

Let's talk about dark energy. We've known for about 20 years that the expansion of our universe is accelerating; every day, our cosmos grows bigger and bigger, doing so faster and faster. It's a subtle effect, and it takes extensive and deep cosmological surveys and studies for scientists to notice it. But multiple independent lines of evidence all point to the same conclusion: accelerating expansion. Astronomers quickly cooked up a cool name for that accelerated expansion: dark energy. But now we’re left with the much harder job of finding a culprit — what's causing it? A universal mistake We use...

The Next Big Discovery in Astronomy? We Probably Found It Years Ago — But Don't Know It Yet By Eileen Meyer, University of Maryland, Baltimore County | June 3, 2018 08:44am ET MORE An artist's illustration of a black hole "eating" a star.Credit: NASA/JPL-Caltech This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights. Earlier this year, astronomers stumbled upon a fascinating finding: Thousands of black holes likely exist near the center of our galaxy. The X-ray images that enabled this discovery weren't from some state-of-the-art new telescope. Nor were...

"We Truly Don't Know What It Is" --Mystery Milky-Way Spectrum of Light Observed 'Not Produced By Any Known Emission' April 17, 2018   "We use special telescopes to catch X-ray light in the sky, and while looking at these X-rays, the telescopes noticed an unexpected feature and captured a spectrum of light, which is not produced by any known atomic emission," said University of Miami astrophysicist Nico Cappelluti. "This emission line is now called the 3.5 kiloelectron volt (keV). One interpretation of this emission line is that it's produced by the decay of dark matter." "This 3.5 keV emission line is...

Using the Hubble Space Telescope astronomers have discovered a nearby galaxy that apparently has little or no evidence of dark matter. The unique galaxy, called NGC 1052-DF2, contains at most 1/400th the amount of dark matter that astronomers had expected. The galaxy is as large as our Milky Way, but it had escaped attention because it contains only 1/200th the number of stars.

Here's a problem: The universe acts like it's a lot more massive than it looks. Take galaxies, those giant, spinning masses of stars. The laws of motion and gravity tell us how fast these objects should turn given their bulk. But observations through telescopes show them spinning way faster than we'd expect, as if they were actually much more massive than the stars we can see indicate. Astrophysicists have come up with two main solutions to this problem. Either there's a lot of mass out there in the universe that we can't detect directly, mass scientists call dark matter, or there's no...

Less than a billion years after the Big Bang, two titans speed toward each other. NRAO/AUI/NSF; D. Berry ======================================================================= Just 780 million years after the universe formed in the Big Bang, two galaxies speed to confront each other in a head-on collision that will lead to a merger between the two—and one of them is towing along a clump of dark matter larger than any spotted before. The research paper, published today in Nature, highlights a little-understood era of the universe known as the Epoch of Reionization. This is when the first galaxies came together and lit up the universe...

The finding keeps open the possibility that the particles come from dark matter New observations of the whirling cores of dead stars have deepened the mystery behind a glut of antimatter particles raining down on Earth from space. The particles are antielectrons, also known as positrons, and could be a sign of dark matter — the exotic and unidentified culprit that makes up the bulk of the universe’s mass. But more mundane explanations are also plausible: Positrons might be spewed from nearby pulsars, the spinning remnants of exploded stars, for example. But researchers with the High-Altitude Water Cherenkov Observatory, or...

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...

To understand this problem, one needs to wrap one’s head around some celestial rotations. Our planet orbits the sun, which, in turn, orbits the center of the Milky Way galaxy. Inside solar systems, the gravitational pull from the mass of the sun and the speed of the planets are in balance. By Newton’s laws, this is why Mercury, the innermost planet in our solar system, orbits the sun at over 100,000 miles per hour, while the outermost plant, Neptune, is crawling at just over 10,000 miles per hour. Now, you might assume that the same logic would apply to galaxies:...

Captured by researchers at the University of Waterloo in Ontario, Canada, the composite image is proof that dark matter acts as a giant intergalactic web that connects galaxies throughout space and time. Their findings were published in Monthly Notices of the Royal Astronomical Society. Dark matter is an invisible force that doesn’t emit or reflect light, and is only detectable through gravity. It makes up around 27 percent of the observable universe and scientists have long predicted that the ghostly substance plays a crucial role in the makeup of our entire universe. “For decades, researchers have been predicting the existence...

Dark matter filaments bridge the space between galaxies in this false colour map. The locations of bright galaxies are shown by the white regions and the presence of a dark matter filament bridging the galaxies is shown in red. Credit: S. Epps & M. Hudson / University of Waterloo ================================================================================================================================ Researchers at the University of Waterloo have been able to capture the first composite image of a dark matter bridge that connects galaxies together. The scientists publish their work in a new paper in Monthly Notices of the Royal Astronomical Society. The composite image, which combines a number of individual...

A new WikiLeaks Vault 7 leak titled “Dark Matter” claims that the Central Intelligence Agency has been bugging “factory fresh” iPhones since at least 2008 through suppliers. The documents are expected to be released after a 10 a.m. EDT “press briefing” that WikiLeaks promoted on its Twitter. And here is the full press release from WikiLeaks: Today, March 23rd 2017, WikiLeaks releases Vault 7 "Dark Matter", which contains documentation for several CIA projects that infect Apple Mac Computer firmware (meaning the infection persists even if the operating system is re-installed) developed by the CIA's Embedded Development Branch (EDB). These documents...

23 March, 2017 Today, March 23rd 2017, WikiLeaks releases Vault 7 "Dark Matter", which contains documentation for several CIA projects that infect Apple Mac Computer firmware (meaning the infection persists even if the operating system is re-installed) developed by the CIA's Embedded Development Branch (EDB). These documents explain the techniques used by CIA to gain 'persistence' on Apple Mac devices, including Macs and iPhones and demonstrate their use of EFI/UEFI and firmware malware. Among others, these documents reveal the "Sonic Screwdriver" project which, as explained by the CIA, is a "mechanism for executing code on peripheral devices while a Mac...