Gravitational Lensing Archives

December 26, 2020February 10, 2021 by Andy Tomaswick

One of the Largest, Most Complete Einstein Rings Ever Seen. Astronomers Call it the “Molten Ring”

The "Molten Ring" is one of the most complete Einstein Rings ever discovered. Credit: NASA

A very rare astronomical phenomenon has been in the headlines a lot recently, and for good reason. It will be hundreds of years until we can see Jupiter and Saturn this close to one another again. However, there are some even more “truly strange and very rare phenomena” that can currently be observed in our night sky. The only problem is that in order to observe this phenomena, you’ll need access to Hubble.

December 13, 2020December 14, 2020 by Matt Williams

If We Used the Sun as a Gravitational Lens Telescope, This is What a Planet at Proxima Centauri Would Look Like

mage of a simulated Earth, at 1024×1024 pixel resolution, at the distance of Proxima Centauri,at 1.3 pc, as projectedby the SGL to an image plane at 650 AU from the Sun. Credit: Toth H. & Turyshev, S.G.

As Einstein originally predicted with his General Theory of Relativity, gravity alters the curvature of spacetime. As a consequence, the passage of light changes as it encounters a gravitational field, which is how General Relativity was confirmed! For decades, astronomers have taken advantage of this to conduct Gravitational Lensing (GL) – where a distant source is focused and amplified by a massive object in the foreground.

In a recent study, two theoretical physicists argue that the Sun could be used in the same way to create a Solar Gravitational Lens (SGL). This powerful telescope, they argue, would provide enough light amplification to allow for Direct Imaging studies of nearby exoplanets. This could allow astronomers to determine if planets like Proxima b are potentially-habitable long before we send missions to study them.

November 27, 2020November 27, 2020 by Paul M. Sutter

A new way to map out dark matter is 10 times more precise than the previous-best method

Simulation of dark matter and gas. Credit: Illustris Collaboration (CC BY-SA 4.0)

Astronomers have to be extra clever to map out the invisible dark matter in the universe. Recently, a team of researchers have improved an existing technique, making it up to ten times better at seeing in the dark.

October 30, 2020October 30, 2020 by Brian Koberlein

Something other than just gravity is contributing to the shape of dark matter halos

The simulated distribution of dark matter in galaxies. Credit: Brinckmann et al.

It now seems clear that dark matter interacts more than just gravitationally. Earlier studies have hinted at this, and a new study supports the idea even further. What’s interesting about this latest work is that it studies dark matter interactions through entropy.

October 8, 2020October 8, 2020 by Brian Koberlein

Gravitational-Wave Lensing is Possible, but it’s Going to be Incredibly Difficult to Detect

This diagram shows how Hubble is able to observe a quasar, a glowing disc of matter around a distant black hole, even though the black hole would ordinarily be too far away to see clearly. Credit: NASA and ESA

Gravity is a strange thing. In our everyday lives, we think of it as a force. It pulls us to the Earth and holds planets in orbits around their stars. But gravity isn’t a force. It is a warping of space and time that bends the trajectory of objects. Throw a ball in deep space, and it moves in a straight line following Newton’s First Law of Motion. Throw the same ball near the Earth’s surface, and it follows a parabolic trajectory caused by Earth’s warping of spacetime around it.

September 14, 2020September 14, 2020 by Brian Koberlein

Small Amounts of Dark Matter are Creating Much Stronger Gravitational Distortions than Anyone Expected to See

A mosaic of telescopic images showing the galaxies of the Virgo Supercluster. It's part of the cosmic web in which a galaxy can exist during part of its evolution. Credit: NASA/Rogelio Bernal Andreo

Dark matter is difficult for astronomers to study, but that doesn’t keep them from trying. And with skill and determination, they continue to find exciting things about the invisible stuff.

August 18, 2020August 18, 2020 by Matt Williams

This Distorted Circle is Actually a Galaxy That Looked Very Similar to the Milky Way, Shortly After the Big Bang

Astronomers using ALMA, in which the ESO is a partner, have revealed an extremely distant galaxy that looks surprisingly like our Milky Way. The galaxy, SPT0418-47, is gravitationally lensed by a nearby galaxy, appearing in the sky as a near-perfect ring of light.

The most widely accepted cosmological view states that the first galaxies formed about 380–400 million years after the Big Bang. These were made up of young, hot stars that lived fast and died young, causing the galaxies themselves to be turbulent. At least, that was the theory until a European team of astronomers observed a galaxy 12 billion light-years away that closely resembled the Milky Way.

Using the Atacama Large Millimeter-submillimeter Array (ALMA), the team observed the galaxy, SPT0418-47, as it appeared when the Universe was just 1.4 billion years old. Much to their surprise, the team noted that the structure and features of this galaxy were highly evolved and stable, something that contradicts previously-held notions about the nature of galaxies in the early Universe.

August 13, 2020August 13, 2020 by Matt Williams

Art Installation that Demonstrates How Dark Matter Bends Light with Gravity

At the Science Gallery of Trinity College Dublin, a beautiful work of art is capturing the imagination of people all over the world. It’s called “Dark Distortions,” a work of interactive art by Dutch artist Thijs Biersteker of Woven Studio. Inspired by the ESA’s forthcoming Euclid mission, a visible to near-infrared space telescope that will launch sometime in 2022 to study the mysterious nature of Dark Matter.

May 20, 2020May 20, 2020 by Brian Koberlein

Hundreds of New Gravitational Lenses Discovered to Help Study the Distant Universe

These two columns show side-by-side comparisons of gravitational lens candidates imaged by the ground-based Dark Energy Camera Legacy Survey (color) and the Hubble Space Telescope (black and white). (Credit: Dark Energy Camera Legacy Survey, Hubble Space Telescope)

General relativity tells us that everything, even light, is affected by the mass of an object. When a beam of light passes near a large mass, its path is deflected. This shift in the direction of light is known as gravitational lensing, and it was one of the first confirmed effects of Einstein’s theory.

April 29, 2020April 30, 2020 by Brian Koberlein

How Do You Weigh The Universe?

How do you weigh everything in the cosmos? Credit: ESO/T. Preibisch

The weight of the universe (technically the mass of the universe) is a difficult thing to measure. To do it you need to count not just stars and galaxies, but dark matter, diffuse clouds of dust and even wisps of neutral hydrogen in intergalactic space. Astronomers have tried to weigh the universe for more than a century, and they are still finding ways to be more accurate.