"This episode is brought to you by the Capital, One saver card, earn four percent cashback on dining and entertainment. Two percent at grocery stores and one percent on all other purchases. Now when you go out you cash in what's in your wallet terms apply. Welcome to brain stuff. A production of iheartradio. Hey, brain stuff. Lauren Bogle bomb here. Dark matter. Sounds a little mysterious because it is it stuff. We can't see with any existing telescopes but that math and physics tells us must exist based on the way that normal matter the stuff we can see babes. And there's a lot of dark matter out there astrophysicists think the twenty-seven percent of the universe is made up of dark matter. Compared with only five percent normal matter, meaning that the term normal probably isn't the most accurate dark matter is the bedrock that all galaxies are anchored to you can't get one without the other. Or so we thought until strana mors found ghostly galaxy. The doesn't appear contain any dark matter. It's as if the universe is planning trick on us by flipping the laws of physics on their head dark matter should be there. But isn't it's a game changer galaxy astronomers are saying, and it's like nothing we've ever seen before we may not be able to spot dark matter. But astronomers can measure its gravitational effects acting on normal matter. For example, they can look at how fast stars cruise around galaxy when dark matters. Isn't that galaxies gravity will be bulked up causing it starts to move faster than if just normal matter were present? But in the case of N, G C one, oh, five two dash d f to an ultra diffuse. Galaxy located sixty five million light years away. Astronomers found that it stars are moving in exactly the way that would be predicted if only the total mass of all the visible stuff is considered. In other words, dark matter doesn't seem to be exerting its gravity on normal matter in that galaxy. And that's weird. Peter von doco of Yale University, sudden statement finding a galaxy without dark matter is unexpected because this invisible mysterious substance is the most dominant aspect of any galaxy for decades without the galaxy start their lives as blobs of dark matter after that everything else, happens guests falls into the dark matter halos, the gas turns into stars. They slowly build up, then you end up with galaxies, like the Milky Way this galaxy challenges the standard ideas of how we think galaxies form ultra diffuse galaxies auditees in their own. Right. Having only been discovered in two thousand fifteen as they are very difficult to detect. However, it appears that this class of galaxy is common but none are like the one in question. The galaxy was discovered using the Dragonfly telephoto array telescope in New Mexico. That's custom made to seek out these allusive targets. Then using a set of twin ten meter optical and infrared telescopes in Hawaii, the Stromer signaled out ten bright, globular clusters, which are large combat groups of stars orbiting the galaxy's core. They let us spectra. Data to measure their motions these clusters were found to be plotting along more slowly than expected. Meaning there's far less mass in that galaxy then would be predicted. In fact, there's so little mass that the researchers have come to the astonishing conclusion that there's little if any dark matter their follow up observations were made with Gemini north telescope. Also in Hawaii. So the galaxy structure could be studied with geminis help the researchers ruled out interactions with other galaxies, as being the cause of it's weird dark matter deficit. Ben dot com said in the press. Release, if there's any dark matter at all. It's very little the stars in the galaxy can account for all of a mass, and there doesn't seem to be any room for dark matter. This finding seems to suggest the dark matter has quote its own separate existence apart from other components of galaxies, he added and this makes the very existence of this galaxy of mystery if it has no dark matter how did even Volve into a galaxy in their study published in March in the journal nature then doco teams speculates that some cataclysmic event in the galaxy. He may have cleared out all the dark matter and blasted away all the star forming gases alternatively a nearby massive, elliptical galaxy may have played a role in the current galaxies lack of dark matter, billions of years ago when it was undergoing, it's early and violent stages of evolution. Now, the researchers are pouring over Hubble space telescopes observations of similar galaxies, to perhaps find more that lack dark matter, if they find more than alternative fuels and faint galaxies might be the norm when dark matter isn't present, and that's a fascinating development in our understanding of how galaxies evolve. Then dot com concluded every galaxy we do about before has dark matter. And they all fall in familiar categories like spiral or elliptical galaxies. But what would you get if there's no dark matter at all? Maybe this is what you would get. Today's episode was written by Dr Ian O'Neill, and produced by Tyler clang brain stuff is a production of iheartradio's, how stuff works for more on this, and lots of other dark topics. Visit our home planet has stuff works dot com and for more podcasts for my heart radio, I heart radio app, apple podcasts or wherever you listen to your favorite shows. Hi there. This is Josh Clark, and I am taking my show, the end of the world. With Josh Clark on the road. Live to Minneapolis in DC this June on June nineteenth, I'll be at the Parkway theater in Minneapolis, Minnesota and on the following night June twentieth. I'll be at the miracle theatre in Washington DC, if you've heard the end of the world ten times already, or if you've never heard a second of it, it matters, not because this show, explores themes, covered in the end of the world and also chases down, new avenues, like, how good could things be if we managed to survive the next century or two. So come see me this June nineteenth and twentieth. Minniap- in DC."