New Hubble data explains missing dark matter

New data from NASA / ESA Hubble Space Telescope provides further evidence for tidal disruption in the Galaxy NGC 1052-DF4. This result explains previous discoveries that this galaxy is missing most of its dark matter. By studying the galaxy’s light and globular cluster distribution, astronomers have concluded that the gravitational forces of the neighboring galaxy NGC 1035 have stripped the black matter from NGC 1052-DF4 and are now tearing the galaxy apart.

In 2018, for the first time, an international team of researchers using NASA / ESA Hubble Space Telescope and many other observations, a galaxy in our cosmic neighborhood that is missing most of its dark matter. This discovery of the Galaxy NGC 1052-DF2 came as a surprise to astronomers as they realized that dark matter (DM) is a key component in current models of galaxy formation and evolution. In fact, without the presence of DAM, there would be a lack of sufficient gravitational pull to start gas breakdown and the formation of new galaxies in the primitive. A year later, another galaxy that missed a dark object was found, NGC 1052-DF4, which sparked intense discussions among astronomers about the nature of these objects.

Now, new Hubble data has been used to explain the reason behind the missing dark object in NGC 1052-DF4, which is 45 million light years away. Miria Montes of the University of New South Wales in Australia led an international team of astronomers to study the galaxy using deep optical imaging. They discovered that the missing dark matter could be explained by the effects of tidal disruption. The gravitational forces of the neighboring giant Galaxy NGC 1035 are tearing apart NGC 1052-DF4. During this process, the dark matter is removed, while the stars experience the effects of interaction with another galaxy at a later stage.

Until now, removing dark matter in this way has been hidden from astronomers, as it can only be observed using extremely deep ND images that can reveal extremely weak features. “We used Hubble in two ways to find out if NGC 1052-DF4 was experiencing an interaction,” Montes explained. “This includes the study of the galaxy’s distribution of light and galactic clusters.”

Thanks to Hubble’s high resolution, astronomers were able to identify the population of the galaxy’s globular clusters. The 10.4-meter Gran Telescopio Canaria (GTC) telescope and the IAC 80 telescope were used in the Canaries of Spain to supplement Hubble’s observations through further study of the data.

“It is not enough to spend a lot of time just inspecting the budget, but it is necessary to treat the data carefully,” explained Ra -l Infante-Sanz, a member of the team from the Instituto de str સ્ટtica cica de Caneria in Spain. We use not only telescopes / instruments, but many (both ground- and space-based). With Hubble’s high resolution, we can identify globular clusters, and then by GTC photometry we get the physical properties. “

Globular clusters form in episodes of intense star formation that shape galaxies. Their compact size and luminosity make them easily observable and so they can better detect the properties of their host galaxy. Thus, by studying and characterizing the spatial distribution of clusters in NGC 1052-DF4, astronomers can develop insights into the current state of the galaxy. The configuration of these clusters suggests that they are being “stripped” from their host galaxy, and this supports the conclusion that tides are being disrupted.

By studying the galaxy’s light, astronomers have also found evidence of tidal tails, which are composed of material moving away from NGC1052-DF4 – further confirming the conclusion that this is a distraction phenomenon. Additional analysis has revealed that the central parts of the galaxy remain untouched and only 7% of the galaxy’s stars are hosted in these tidal tails. This means that the dark matter, which is less concentrated than the stars, was previously and preferably stripped from the galaxy, and is now being stripped of the outer stellar component as well.

“This result is a good indicator that, when the dark matter of the galaxy evaporated from the system, the stars are now beginning to suffer from the disruption system,” explained Ignacio Trujillo, a member of Spain’s Instituto de Astrophasica de Caneria. “Over time, NGC1052-DF4 could be alerted by the large system surrounding NGC 1035, at least some of their stars will be floating free in deep space.”

The search for evidence to support the mechanism of tidal collapse, as revelations about the galaxy’s missing dark matter have not only solved the astronomical conundrum, but also brought a sigh of relief to astronomers. Without it, scientists would have to improve our understanding of the laws of gravity.

“This discovery reconciles existing knowledge of how galaxies form and evolve with a highly favorable cosmological model,” Montes added.

These results have been published Astrophysical Journal.