Galaxies Without Dark Matter
Some time ago, astronomers found 6 galaxies that seemed to have no dark matter. First, they were told to look again, as everyone assumed they just missed it. So they did. With an array of radio telescopes, they searched for dark matter in the galaxy AGC 114905 and they still didn’t find any.
Image by Luminas Art from Pixabay
- Be also sure to check out my other posts and follow me @kralizec and subscribe to my Youtube channel at Kralizec Gaming Youtube Channel
A simple question that over time became one of the hardest to answer mysteries in astronomy. Can galaxies without dark matter exist? Regularly, we see scientific studies that convincingly confirm the possibility of the existence of such galaxies only to have works of science dismiss such an idea come right after. The result is chaos and everyone who loves science doesn’t even have time to read all the news.
One of the newest pieces in this wild discussion is the research coming from an international team of astronomers that were repeatedly and really hard searching for dark matter in the galaxy AGC 114905. Pavel Mancera Piña and his colleagues spent 40 hours using powerful telescopes and… nothing.
The researchers first discovered 6 galaxies that seemed to have no or practically no dark matter. So, they were told to look again and harder as others were certain they just missed it. Thus Piña and his colleagues fully tried out the capabilities of the Very Large Array (VLA) array of telescopes in New Mexico to observe the galaxy AGC 114905. The focused on the movement of gas in the galaxy. Yet, no dark matter was found and it truly seems there is no there. The movement of the gas in the galaxy can be fully explained without dark matter.
The galaxy AGC 114905 is about 250,000,000 light-years away from us. It is an ultra-thin dwarf galaxy. In this case, the word dwarf doesn’t mean its size but its radiation output. It is actually roughly the size of our own Milky Way just comes with roughly 1000 times fewer stars. Mainstream physics says galaxies are held together by dark matter and it should stand true for ultra-thin dwarf galaxies especially.
The authors of the study also assessed possible explanations of their observations. But they aren’t exactly great. One of them says the dark matter could have been stolen by some nearby galaxies. Sounds good right? Sadly, there are no galaxies nearby. Modified Newtonian Dynamics (MOND) – an alternative theory for explaining the movement of matter in galaxies – doesn’t seem to do the job either.
For the time being, the questions remain unanswered. The researchers are now studying in great detail another ultra-thin dwarf galaxy and if they don’t find any dark matter their either maybe, we will confirm that galaxies do not need dark matter to exist.
Sources:
- If you like the content I’m producing about science maybe you will like the content I produce about gaming as well! Be sure to check out my other posts!