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Archive for the ‘cosmology’ category: Page 16

Nov 13, 2024

A Supermassive Black Hole Shot A Light-Speed Jet Pointing Straight Toward Earth

Posted by in category: cosmology

Astronomers have found a supermassive black hole ejecting a jet of energy at nearly the speed of light. This event, called AT2022cmc, is the most distant tidal disruption event (TDE) ever recorded, taking place 12.4 billion light years away from Earth. The international team of researchers shared their findings in papers published on November 30 in Nature and Nature Astronomy, noting that this TDE was observable due to the intense brightness of its jet and the direction it pointed—right toward Earth.

Igon Andreoni, an astronomer at the University of Maryland and co-leader of the study, emphasized how unusual it is to witness such a jet, as it must be aimed almost directly at Earth for detection. The light from AT2022cmc reached Earth after traveling across space for approximately 8.5 billion years, implying that this event happened when the universe was just a third of its current age.

The observation has led researchers to propose that the black hole involved was spinning at a high rate, which likely contributed to the formation of the jet. Despite its classification as “supermassive,” this black hole’s mass, estimated at a few hundred million times that of the Sun, is typical for black holes at the centers of galaxies.

Nov 12, 2024

A black hole’s secrets could hide in its dizzying light ‘echoes’

Posted by in category: cosmology

Black hole light echoes are an extreme form of gravitational lensing.

Nov 12, 2024

Neutron Stars may be Shrouded in Axions

Posted by in categories: cosmology, particle physics

Physicists show that neutron stars may be shrouded in clouds of ‘axions’ — and that these clouds can teach us a lot. A team of physicists from the universities of Amsterdam, Princeton and Oxford have shown that extremely light particles known as axions may occur in large clouds around neutron stars. These axions could form an explanation for the elusive dark matter that cosmologists search for — and moreover, they might not be too difficult to observe.

Nov 12, 2024

Star’s disappearance in Andromeda marks the birth of a black hole

Posted by in category: cosmology

Massive stars about eight times more massive than the sun explode as supernovae at the end of their lives. The explosions, which leave behind a black hole or a neutron star, are so energetic they can outshine their host galaxies for months. However, astronomers appear to have spotted a massive star that skipped the explosion and turned directly into a black hole.

Nov 12, 2024

Heavy-ion run at the LHC begins

Posted by in categories: cosmology, particle physics

The Large Hadron Collider (LHC) is like an immensely powerful kitchen, designed to cook up some of the rarest and hottest recipes in the universe, like the quark–gluon plasma, a state of matter known to have existed shortly after the Big Bang. While the LHC mostly collides protons, once a year it collides heavy ions—such as lead nuclei—a key ingredient for preparing this primordial soup.

Nov 11, 2024

Saturday Citations: Color vision created demand for colorful animals; observing black hole light echoes; deadlines!

Posted by in categories: cosmology, evolution

A new statistical analysis by researchers at the University of Arizona suggests that evolved in animals around 500 million years ago, long before the evolution of colorful fruits and flowers, which started sprouting 200 to 350 million years ago. The researchers focused on what they term “conspicuous colors”—basically, the ones kids are likeliest to select in a 16 pack of Crayolas—red, orange, yellow, blue and purple.

Around 150 million years ago, presumably to capitalize on the well-established prevalence of color vision, species began evolving warning coloration. And 50 million years later, there was an evolutionary explosion of both warning and sexual coloration. Although the reasons behind this evolutionary burst are still unclear, the researchers identified three warning signal animal vectors behind it: ray-finned fishes, birds and lizards.

Additionally, warning coloration is much more widespread among species than sexual coloration, likely because colorful animals do not themselves need to have color vision to signal the danger they pose to other, color-sensitive species. Sexual color signals, on the other hand, are confined to vertebrate and arthropod species that have well-developed color vision.

Nov 11, 2024

‘Hawking radiation’ may be erasing black holes. Watching it happen could reveal new physics

Posted by in categories: cosmology, physics

Primordial black holes may be exploding throughout the universe. If we can catch them in the act, it could pave the way to new physics, a study suggests.

Nov 11, 2024

Scientists successfully hear the chorus of gravitational waves that ripple through the universe

Posted by in categories: cosmology, physics

Scientists recently reported a monumental discovery in astrophysics: the detection of low-frequency gravitational waves. This breakthrough was made by NANOGrav (North American Nanohertz Observatory for Gravitational Waves), which released findings in The Astrophysical Journal Letters. These waves, predicted by Einstein, are generated when massive objects like supermassive black holes interact, creating cosmic ripples across spacetime. For the first time, researchers have managed to “hear” these background vibrations of the universe, likened to the faint, low hum in a cosmic orchestra. This detection not only broadens our understanding of gravitational waves but also opens up a new chapter in studying the universe’s largest objects and events.

Nov 11, 2024

The Big Bang Is Beyond Doubt. An Expert Reveals Why

Posted by in category: cosmology

How did everything begin? It’s a question that humans have pondered for thousands of years. Over the last century or so, science has homed in on an answer: the Big Bang.

This describes how the Universe was born in a cataclysmic explosion almost 14 billion years ago. In a tiny fraction of a second, the observable universe grew by the equivalent of a bacterium expanding to the size of the Milky Way. The early universe was extraordinarily hot and extremely dense. But how do we know this happened?

Continue reading “The Big Bang Is Beyond Doubt. An Expert Reveals Why” »

Nov 10, 2024

A Supermassive Black Hole Is Heading Earth’s Way At 110 Km Per Second

Posted by in category: cosmology

There is a massive black hole with millions of times more mass than our sun is plunging towards Earth and will one day annihilate life as we know it. This particular black hole is coming towards us at 110 kilometres per second and is at the center of the Great Andromeda Galaxy – the Milky Way’s closest and much larger neighbor.

At the center of the most known galaxies, there exist a supermassive black hole which stars spin around and helps keep everything in formation. But such is the powerful gravitational pull of the Milky Way and Andromeda that they are being drawn toward each other and will one day crash.

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