Space and astronomy news
A team of astronomers has claimed that observations of a sun-like star orbiting a small black hole might actually be the indication of something far more exotic – the existence of a boson star, a star composed entirely of dark matter.
Continue reading “This Star Might be Orbiting a Strange “Boson Star””
A team of theoretical astrophysicists have studied in detail a hypothetical form of dark matter that combines to form dark atoms. They found that the existence of dark atoms can drastically affect the evolution of galaxies.
Continue reading “Dark Matter Can Make Dark Atoms”
According to the most widely-accepted cosmological model, the majority of the mass in our Universe (roughly 85%) consists of “Dark Matter.” This elusive, invisible mass is theorized to interact with “normal” (or “visible”) matter through gravity alone and not electromagnetic fields, neither absorbing nor emitting light (hence the name “dark”). The search for this matter is ongoing, with candidate particles including Weakly-Interacting Massive Particles (WIMPs) or ultralight bosons (axions), which are at opposite extremes of the mass scale and behave very differently (in theory).
This matter’s existence is essential for our predominant theories of gravity (General Relativity) and particle physics (The Standard Model) to make sense. Otherwise, we may need to radically rethink our theories on how gravity behaves on the largest of scales (aka. Modified Gravity). However, according to new research led by the University of Hong Kong (HKU), the study of “Einstein Rings” could bring us a step closer to understanding Dark Matter. According to their paper, the way Dark Matter alters the curvature of spacetime leaves signatures that suggest it could be made up of axions!
Continue reading “Gravitational Lensing is Helping to Nail Down Dark Matter”
Testing the possibility of models of gravity different from general relativity may be closer to home than we think. A team of researchers has proposed that we might be able to use seismic motions in the Earth itself to test for modified gravity.
Continue reading “We Might be able to Find Evidence for Modified Gravity…in the Earth”
Our universe may feature large, macroscopic clumps of dark matter, known as q-balls. These q-balls would be absolutely invisible, but they may reveal their presence through tiny magnifications of starlight.
Continue reading “Astronomers Go Hunting for Mysterious Q-balls”
What contains a petabyte of data on more than a billion galaxies in one of the most extensive sky maps? The answer: the ever-expanding Dark Energy Spectroscopic Instrument (DESI) Legacy Imaging Survey. The galaxies it charts are part of the largest two-dimensional map of the sky ever made. And, just recently, it grew even larger with the addition of new data from telescopes in the U.S. and Chile.
Continue reading “A New Survey of the Sky Contains Over One Billion Galaxies”
Astronomers have discovered a galaxy with very little or no stellar mass. Galaxies like these are called ‘dark galaxies.’ It contains clouds of gas but very few stars, possibly none. This is the only isolated dark dwarf galaxy in the local universe.
Continue reading “A Galaxy has Been Found that’s Almost Entirely Dark Matter”
Although dark matter is a central part of the standard cosmological model, it’s not without its issues. There continue to be nagging mysteries about the stuff, not the least of which is the fact that scientists have found no direct particle evidence of it. Despite numerous searches, we have yet to detect dark matter particles. So some astronomers favor an alternative, such as Modified Newtonian Dynamics (MoND) or modified gravity model. And a new study of galactic rotation seems to support them.
Continue reading “New Measurements of Galaxy Rotation Lean Towards Modified Gravity as an Explanation for Dark Matter”
For decades, astrophysicists have theorized that the majority of matter in our Universe is made up of a mysterious invisible mass known as “Dark Matter” (DM). While scientists have not yet found any direct evidence of this invisible mass or confirmed what it looks like, there are several possible ways we could search for it soon. One theory is that Dark Matter particles could collide and annihilate each other to produce cosmic rays that proliferate throughout our galaxy – similar to how cosmic ray collisions with the interstellar medium (ISM) do.
This theory could be tested soon, thanks to research conducted using the A Large Ion Collider Experiment (ALICE), one of several detector experiments at CERN’s Large Hadron Collider (LHC). ALICE is optimized to study the results from collisions between nuclei that travel very close to the speed of light (ultra-relativistic velocities). According to new research by the ALICE Collaboration, dedicated instruments could detect anti-helium-3 nuclei (the anti-matter counterpart to He3) as they reach Earth’s atmosphere, thus providing evidence for DM.
Continue reading “Anti-Helium Generated in the Large Hadron Collider can Help in the Search for Dark Matter”
As we’ve noted in plenty of other articles, science also moves forward by constraints. Understanding the limits of a physical phenomenon helps to develop better methods of looking for it, especially in its absence. Dark matter is an archetype of a missing phenomenon, but there are plenty of potential explanations for it. One of them is known as the axion, which was originally developed as a hypothetical particle that could plug a hole in the Standard Model of particle physics but could also solve the problem of dark energy. That is if they actually exist. Now a new experiment from researchers at CERN can help the scientific community better define where to look for those axions.
Continue reading “If Dark Matter is Made of Axions, This Could be the Detector That Finds Them”