A year ago, the science world was taken aback by the discovery of a new galaxy. You might think that astronomers and astrophysicists’ discovery of new galaxies is a common occurrence. Well, yes, maybe it is. But there are not many galaxies that put to the test the fundamental laws of physics, are there? This is what scientists believed the new galaxy was – an anomaly. It turns out it was not.
NGC 1052-DF2 is a very faint galaxy which can be found in the Cetus constellation. The galaxy was first spotted by the Dragonfly Telephoto Array, a ground-based telescope, which, in turn, was inspecting the NGC 1052 group. The scientists that discovered it announced to the whole wide world the peculiarity of the galaxy – it had no dark matter.
As we all know, all galaxies are formed from dark matter in combination with cosmic dust and gas. Therefore, it is expected that each galaxy has a dark matter in its composition. The fact that NGC 1052-DF2 lacked the matter only meant that theories about the formation of galaxies and the universe were wrong, or at least needed reexamination. It also proved that dark matter was real and that it had an autonomous existence.
Dark matter continues to be elusive
Constant observations in the last year proved the first theories wrong. Recent research conducted by a different team than the first one indicated, after using a broad observing set of data, that dark matter might be present in the galaxy after all. The new team found many inaccuracies with the data presented in 2018. The distance between NGC 1052-DF2 and our planet was said to be around 64 million light-years, while in reality is only 42 million light-years away.
The actual total mass of the galaxy is half of what was presented a year ago, while the mass of the stars that are part of the newly-discovered galaxy is a quarter lower than it was said. These facts imply that a significant portion of the galaxy might be composed of dark matter. These numbers add up as we know that dark matter comprises 85% of the matter of the universe.
Earlier this year, another galaxy that is believed lacks dark matter was discovered. NGC 1052-DF4 presents almost the same data as MGC 1052-DF2 as both are faint galaxies. Studies are still underway to determine other characteristics of the galaxy and whether it contains dark matter or not. The importance of finding these galaxies relies on the fact that, if dark matter is not found, scientists must revise the theories of the universe.
Jasmine holds a Master’s in Journalism from Ryerson University in Toronto and writes professionally in a broad variety of genres. She has worked as a senior manager in public relations and communications for major telecommunication companies, and is the former Deputy Director for Media Relations with the Modern Coalition. Jasmine writes primarily in our LGBTTQQIAAP and Science section.