Einstein Ring Reveals Mystery of Dark Matter

(Dan Tri) - According to researchers, this may be the smallest pure dark matter mass ever discovered.

Strange object, discovered for the first time

The object appears in infrared light, depicted in white (Image source: Research team).

A dark matter mass has just been discovered with a mass 1 million times larger than the Sun, located about 10 billion light years away from us, and especially has no stars at all.

This makes it a strong candidate for the smallest pure dark matter clump ever recorded. The discovery not only strengthens the cold dark matter (CDM) model, but also places tighter limits on the nature and behavior of dark matter particles, as physicists and astronomers continue to hunt for the “invisible stuff” that governs the structure of the universe.

The discovery came from observations of Einstein rings, a phenomenon of gravitational lensing in which large foreground masses distort space and bend light from background galaxies to form a ring of light around the foreground galaxy.

Interestingly, scientists only accidentally found the strange object while analyzing radio-light tornado images combined with infrared images.

Specifically, they observed an unusual notch in the bright ring, which can only be explained by the presence of an invisible mass between the light path and the observation point.

To understand this phenomenon, the team used a global network of radio telescopes to create an “Earth-sized telescope” with extremely high resolution. The larger the baseline, the more detail the team could see in the lensed light structure.

Upon closer inspection, they noticed a “notch” in the arc of radio light, a phenomenon that could only be explained by a massive object located between the background and foreground galaxies.

The key to understanding the nature of dark matter

Einstein's ring may have helped humanity find the smallest dark matter (Photo: Research team).

The observational data are consistent with the cold dark matter model, which is a cornerstone of our understanding of how galaxies form over time, the team said.

“Detecting low-mass objects like this is key to understanding the nature of dark matter,” said team member Chris Fassnacht.

However, there are currently two separate hypotheses for this object. In the first case, the object could be a dormant dwarf galaxy. In the second case, the object is a completely pure mass of dark matter, meaning it has no stellar components at all.

If it can be confirmed that this is a dark matter clump, it would be the smallest dark object ever discovered, being nearly 100 times smaller than previously observed dark objects.

Accordingly, this discovery is not only a milestone in astronomy but also a challenge to dark matter theory: can we believe that dark matter is evenly distributed and smooth, or is it really "concave" with very small pure blocks?

What is the phenomenon of gravitational lensing – Einstein rings?

Gravitational lensing is the phenomenon of light from a distant object (such as a galaxy or quasar) being bent when passing through a region of space with very large mass (such as a galaxy, galaxy cluster, or black hole).

When the light source, the bent object, and the observer are all aligned almost perfectly, the light is bent into a complete circle of light, called an Einstein ring, first predicted by Albert Einstein in 1936.

This phenomenon helps astronomers “see” non-luminous objects like dark matter, because it reveals invisible mass that is distorting space.

Source: https://dantri.com.vn/khoa-hoc/vong-einstein-he-lo-bi-an-ve-vat-chat-toi-20251014084039095.htm