Space and astronomy news
According to our predominant cosmological models, Dark Matter makes up the majority of mass in the Universe (roughly 85%). While it is not detectable in visible light, its influence can be seen based on how it causes matter to form large-scale structures in our Universe. Based on ongoing observations, astronomers have determined that Dark Matter …
Continue reading ““Seeing” the Dark Matter Web That Surrounds the Coma Cluster”
Astronomers aren’t sure what dark matter is, but they carefully observe to determine which models best match the data. Astronomers have recently developed a method to measure the speed of dark matter compared to other objects in the Universe. As a cloud of dark matter moves past a galaxy, gravity pulls particles towards it in a curving trajectory. The speed of the dark matter can be measured through its effects on the galaxy and vice versa.
Science really does keep you on your toes. First there was matter and then there were galaxies. Then those galaxies had more stuff in the middle so stars further out were expected to move slowly, then there was dark matter as they actually seemed to move faster but now they seem to be moving slower …
Continue reading “There’s Less Dark Matter at the Core of the Milky Way”
There’s a galaxy out there without apparent stars but largely chock full of dark matter. What’s that you say? A galaxy without stars? Isn’t that an impossibility? Not necessarily, according to the astronomers who found it and are trying to explain why it appears starless. “What we do know is that it’s an incredibly gas-rich …
Continue reading “A Primordial Dark Matter Galaxy Found Without Stars”
Even though we still don’t know what dark matter is, astronomers can use it as a natural telescope lens with gravitational lensing. A new theoretical paper suggests that mini-halos of dark matter in the early Universe could be used as a probe to map out primordial magnetic fields. These magnetic fields are everywhere in the cosmos today, but were they produced in the early stages of the Universe? It depends on the influence of magnetic fields on dark matter.
One of the aspects of our study of the universe that fascinates me is the hunt for dark matter. That elusive material that doesn’t interact with much makes it difficult but not impossible to detect. Gravitational lenses are one such phenomena that point to its existence indeed it allows us to estimate how much there …
Continue reading “Dark Matter Could Cause Jupiter’s Night Side to Glow”
One outstanding mystery in astrophysics is known as the “final parsec problem.” Simulations predict that binary black holes should stall out in the last stages of their merger. Since we’re detecting the gravitational waves from these mergers, we know it happens, but how? A new paper proposes that ultralight dark matter near the black holes could help to carry away orbital energy from the black holes, driving them together.
Thanks to new techniques, astronomers are mapping the Universe with more precision, finding galaxies with more and less dark matter. Now astronomers think they’ve found one that’s almost all dark matter with few stars. Dubbed “Nube”, the galaxy contains about the same mass as the Large Magellanic Cloud, measuring 22,000 light-years across, with almost no stars inside it. This is the most massive and extended “Almost Dark Galaxy” astronomers have ever found.
The search for dark matter continues, with astronomers developing new hypotheses to search for this invisible gravitational influence on the Universe. One proposed dark matter particle candidate is the axion, which physicists have searched for since the 1970s. One characteristic of axions is that they should convert into light in a strong electromagnetic field. According to a new paper, they should create a faint glow around pulsars, generating intense magnetic fields.
Astronomers still don’t know what dark matter is, but one of its characteristics is that it has a small “cross section,” which means that it doesn’t interact with regular matter or itself. However, if it’s possible to trap dark matter in a region dense enough, it might interact and annihilate, releasing gamma radiation. A new paper suggests that astronomers use gamma-ray observatories to scan white dwarf stars to discover whether there’s an excess of radiation coming from them. This might mean there’s dark matter trapped inside, providing more clues to its nature.