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Archive for the ‘cosmology’ category: Page 130

Feb 20, 2023

What Is dark energy?

Posted by in categories: cosmology, physics

Dark energy is the name physicists have given to the mysterious thing driving the universe’s accelerated expansion. It may be a force or a form of energy, and one piece of evidence suggests it is hidden inside black holes.

Feb 20, 2023

Elusive ‘Buchdahl stars’ are black holes without event horizons. But do they really exist?

Posted by in category: cosmology

These hypothetical stars are the densest objects in the universe that can exist without becoming full-fledged black holes.

Feb 20, 2023

Scientists discovered evidence of magnetic fields in the universe’s cosmic web

Posted by in category: cosmology

The cosmic web is the term used to refer to the clusters, filaments, and voids that make up the large-scale structure of the Universe. In Λ cold dark matter (ΛCDM) cosmology, this web is formed from the anisotropic gravitational collapse of matter from primordial overdensities.

We’ve been able to map the Cosmic Web through observation over the past few decades, which opens up the possibility of finding answers to some of astronomy’s most pressing issues. An area of particular interest is how magnetic fields behave on a cosmic scale and their role in galactic and cosmic structure formation.

ICRAR scientists discover tantalizing evidence of magnetic fields in the universe’s most significant cosmic structures.

Feb 19, 2023

Closest Known Black Hole to Earth Identified Using ESA’s Gaia Astrometry Mission

Posted by in category: cosmology

Using data from ESA’s Gaia astrometry mission, astronomers have identified the closest known black hole.

A black hole is a place in space where the gravitational field is so strong that not even light can escape it. Astronomers classify black holes into three categories by size: miniature, stellar, and supermassive black holes. Miniature black holes could have a mass smaller than our Sun and supermassive black holes could have a mass equivalent to billions of our Sun.

Feb 19, 2023

The universe keeps dying and being reborn, claims Nobel Prize winner

Posted by in categories: cosmology, physics

Sir Roger Penrose, a mathematician and physicist from the University of Oxford who recently shared this year’s Nobel Prize in physics, says that our universe has undergone numerous Big Bangs, with another one on the way.

Feb 19, 2023

Astronomers uncovered footprints of galactic immigration in Andromeda galaxy

Posted by in category: cosmology

Throughout billions of years, galaxies expand and evolve through the appropriately titled “galactic immigration” events, which involve the formation of new stars and mergers with other galaxies. Scientists examine the movements of individual stars within a galaxy and its wide halo of stars and dark matter to learn more about the histories of these immigration episodes. But until now, such cosmic archaeology has only been possible in our galaxy, the Milky Way.

An international team of researchers has uncovered striking new evidence of a large galactic immigration event in the Andromeda Galaxy. Star motions exhibit complex patterns indicating migratory history similar to the Milky Way. The new findings were attained using Nicholas U.’s Dark Energy Spectroscopic Instrument, which the DOE operates.

A team of astronomers studied the motions of nearly 7,500 stars in the inner halo of the Andromeda Galaxy, also known as Messier 31 (M31). They found patterns in their positions and motions that indicated how these stars originated as a part of an earlier galaxy that joined M31 about 2 billion years ago. Although such patterns have long been anticipated by theory, they have never been observed in a galaxy with such clarity.

Feb 19, 2023

String Theory Reveals the Multiverse

Posted by in categories: cosmology, particle physics, quantum physics

Year 2020 :3.


Atoms are made of protons, neutrons and electrons. And they are small. So small that 100 million hydrogen atoms would span the width of your fingernail. String theory proposes that at the most fundamental level of space there are objects that are much smaller than these elementary particles: tiny little filaments of energy, called “strings.”

Feb 19, 2023

Two Supermassive Black Holes Are Expected To Collide Within Next 3 Years And We Will Watch It In Real-Time

Posted by in category: cosmology

One of the most awaited events in modern astronomy may be upon us shortly, according to experts.

Feb 18, 2023

Scientists Find One of the Most Massive Black Holes With 34 Billion Times The Mass of Our Sυn

Posted by in category: cosmology

Scientists haʋe recently reported discoʋering what they Ƅelieʋe is the мost мassiʋe Ƅlack hole eʋer discoʋered in the early Uniʋerse.

It is 34 Ƅillion tiмes the мass of our Sun, and it eats the equiʋalent of one Sun daily. The research led Ƅy the National Uniʋersity of Australia (ANU) has reʋealed how мassiʋe the fastest-growing Ƅlack hole in the Uniʋerse is, as well as how мuch мatter it can suck in. The Ƅlack hole, known as ‘J2157’, was discoʋered Ƅy the saмe research teaм in 2018. The study detailing the huмongous Ƅlack hole’s characteristics has Ƅeen puƄlished in Monthly Notices of the Royal Astronoмical Society. According to Dr. Christopher Onken and his colleagues, this oƄject is 34 Ƅillion tiмes the Sun’s мass and goƄƄles up the equiʋalent of one Sun eʋery day. That’s a Ƅillion with a Ƅ.

For other coмparisons, the мonstrous Ƅlack hole has a мass of approxiмately 8,000 tiмes that of Sagittarius A*, the Ƅlack hole located at the center of the Milky Way galaxy. “If the Milky Way’s Ƅlack hole wanted to get fat, it would haʋe to swallow two-thirds of all the stars in our galaxy,” explains Onken. Scientists studied the oƄject at a tiмe when the Uniʋerse was only 1.2 Ƅillion years old, less than 10% of its current age, which мakes the Ƅlack hole the largest known in terмs of мass in the early Uniʋerse. “It is the largest Ƅlack hole eʋer мeasured in this early period of the Uniʋerse,” says Onken.

Feb 18, 2023

Why are small black holes more dangerous than big ones?

Posted by in categories: cosmology, information science

Why would someone falling into a stellar-mass black hole be spaghettified, but someone crossing the event horizon of a supermassive black hole would not feel much discomfort?

As it turns out, there is a relatively simple equation that describes the tidal acceleration that a body of length d would feel, based on its distance from a given object with mass M: a = 2GMd/R3, where a is the tidal acceleration, G is the gravitational constant, and R is the body’s distance to the center of the object (with mass M).