Gravitational lens, as observed by the Hubble Space Telescope.In this picture a galactic cluster, about five billion light-years away, produces a tremendous gravitational field that “bends” light around it. The phenomenon occurs when a huge amount of matter, such as a massive galaxy or cluster of galaxies, creates a gravitational field that distorts and magnifies the light from objects behind it, but in the same line of sight, NASA explained on its website. It offers excellent evidence to differentiate between competing theories.

This lens produces multiple copies of a blue galaxy about twice as distant. And once you’re bending light, well, you’ve got yourself a telescope. Thanks for A2A. In general relativity, the presence of matter (energy density) can curve spacetime, and the path of a light ray will be deflected as a result. Gravitational lensing works like this: When a large nearbyobject like a galaxy blocks a distant object, such as another galaxy, the lightcan detour around the blockage. Not only does it tug away at you, me, planets, moons and stars, but it can even bend light itself.

While gravitational lensing has existed throughout history, it's fairly safe to say that it was first discovered in the early 1900s. Well,gravity’s a funny thing. The probability of arcs present in any given galaxy or galaxy cluster helps to determine the overall mass of dark matter within the lens as well as constrain the mass density of the Universe (Cooray, 1999).

Like a billiard ball sinking into a stretched-out rubber sheet, a massive object creates a depression around it; it’s called a "gravity well." But theorist still argue. glass) lenses in optics. Light passing through a gravity well bends with its curves. Gravitational lensing is a particularly important effect.

Stars and planets can cause gravitational lensing effects, although those are hard to detect.

Today, it is used to study many phenomena and objects in the distant universe.

Lensing has also been used to help verify the existence of dark matter itself.

Gravitational lensing was predicted by Einstein’s theory of general relativity. For this, they will take the help of a natural phenomenon called “gravitational lensing”. Lensing can help astronomers work out exactly how much dark matter there is in the Universe as a whole and also how it is distributed. Gravitational Lensing. This process is called gravitational lensing and in many cases can be described in analogy to the deflection of light by (e.g. General relativity posited that massive objects like the sun actually bend the fabric of spacetime around them. Gravitational lensing is useful to cosmologists because it is directly sensitive to the amount and distribution of dark matter.

The weak gravitational lensing is used instead to map the overall distribution of dark matter within the halo of galaxies, or within the spaces between galaxies in a galaxy cluster.

Four images are visible in a circle surrounding the lens; a fifth is visible near the centre of the picture.