Dark matter is the mysterious structure that’s a lot more prevalent in the Universe than the usual matter that we all know. If the latter accounts for just about 4% of the total mass of our Cosmos, the former is a lot more widespread: about 27%. The rest of the Universe consists of dark energy, the mysterious “engine” behind the expansion of our Cosmos itself.
Therefore, common sense tells us that finding an entire galaxy that completely lacks dark matter should be impossible. But astronomy once again proves us wrong. And after all, that’s the whole beauty of science: learning new and surprising information.
No dark matter present in AGC 114905
AGC 114905 is the name of a galaxy located at a staggering distance of 250 million light-years away. That means the galaxy was there “only” 20 million years before the dinosaurs first appeared on Earth. Using state-of-the-art telescopes, an international team of astronomers has found no signs of dark matter in the galaxy, according to SciTechDaily.com.
AGC 114905 is not peculiar only for lacking any dark matter as far as scientists could explore. Despite being just about the same size as our own Milky Way galaxy, the AGC 114905 galaxy contains about a thousand times fewer stars. The dark matter lacking galaxy is classified as an ultra-diffuse dwarf galaxy.
Using the VLA telescope, astronomers collected data regarding the rotating gas from the AGC 114905 galaxy for 40 hours in 2020, between July and October. They also made a graph that presents the gas in a more detailed way, trying to detect dark matter.
Pavel Mancera Piña from the University of Groningen, declared as quoted by SciTechDdaily.com:
This is, of course, what we thought and hoped for because it confirms our previous measurements,
But now the problem remains that the theory predicts that there must be dark matter in AGC 114905, but our observations say there isn’t. In fact, the difference between theory and observation is only getting bigger.
The new findings are awaited for publication in Monthly Notices of the Royal Astronomical Society