Gravitational Lensing Archives

December 21, 2022December 21, 2022 by Evan Gough

Webb Stares Deeply Into the Universe, Showing How Galaxies Assemble

This image represents a portion of the full PEARLS field, which will be about four times larger. Thousands of galaxies over an enormous range in distance and time are seen in exquisite detail, many for the first time. Image Credit: SCIENCE: NASA, ESA, CSA, Rolf A. Jansen (ASU), Jake Summers (ASU), Rosalia O'Brien (ASU), Rogier Windhorst (ASU), Aaron Robotham (UWA), Anton M. Koekemoer (STScI), Christopher Willmer (University of Arizona), JWST PEARLS Team IMAGE PROCESSING: Rolf A. Jansen (ASU), Alyssa Pagan (STScI)

The James Webb Space Telescope is delivering a deluge of images and data to eager scientists and other hungry-minded people. So far, the telescope has shown us the iconic Pillars of Creation like we’ve never seen them before, the details of very young stars as they grow inside their dense cloaks of gas, and a Deep Field that’s taken over from the Hubble’s ground-breaking Deep Field and Ultra Deep Field images. And it’s only getting started.

True to its main science objectives, the JWST has peered back in time to the Universe’s earliest galaxies looking for clues to how they assemble and evolve.

October 28, 2022October 28, 2022 by Brian Koberlein

JWST Sees the Same Galaxy From Three Different Angles Thanks to a Gravitational Lens

This illustration shows how gravitational lensing works. The gravity of a large galaxy cluster is so strong, it bends, brightens and distorts the light of distant galaxies behind it. The scale has been greatly exaggerated; in reality, the distant galaxy is much further away and much smaller. Credit: NASA, ESA, L. Calcada

One of the great tragedies of the night sky is that we will never travel to much of what we see. We may eventually travel to nearby stars, and even distant reaches of our galaxy, but the limits of light speed and cosmic expansion make it impossible for us to travel beyond our local group. So we can only observe distant galaxies, and we can only observe them from our home in the universe. You might think that means we can only see one face of those galaxies, but thanks to the James Webb Space Telescope that isn’t entirely true.

October 7, 2022October 7, 2022 by Nancy Atkinson

Webb and Hubble Work Together to Reveal This Spectacular Galaxy Pair — and Several Bonuses!

By combining data from the James Webb Space Telescope and the Hubble Space Telescope, this image of galaxy pair VV 191 includes near-infrared light from Webb, and ultraviolet and visible light from Hubble. Credit: NASA, ESA, CSA, Rogier Windhorst (ASU), William Keel (University of Alabama), Stuart Wyithe (University of Melbourne), JWST PEARLS Team, Alyssa Pagan (STScI).

What’s better than a pair of galaxies observed by a pair of iconic space telescopes? The answer to that, according to researchers using the Hubble and James Webb Space Telescopes, is finding even more galaxies and other remarkable details no one expected in the duo’s observations.

“Galaxies in the foreground, background, deep background, and into the depths,” said astronomer William Keel from Galaxy Zoo, on Twitter.

October 7, 2022October 7, 2022 by Brian Koberlein

A Solar Gravitational Lens Will be Humanity's Most Powerful Telescope. What are its Best Targets?

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.

One of the central predictions of general relativity is that a massive object such as a star, galaxy, or black hole can deflect light passing nearby. This means that light from distant objects can be gravitationally lensed by objects closer to us. Under the right conditions, gravitational lensing can act as a kind of natural telescope, brightening and magnifying the light of distant objects. Astronomers have used this trick to observe some of the most distant galaxies in the universe. But astronomers have also thought about using this effect a little closer to home.

September 30, 2022September 30, 2022 by Nancy Atkinson

A Computer Algorithm is 88% Accurate in Finding Gravitational Lenses

Pictures of gravitational lenses from the AGEL survey. Credit: ARC Centre of Excellence for All Sky Astrophysics in 3-Dimensions (ASTRO3D) and the University of NSW (UNSW).

Astronomers have been assessing a new machine learning algorithm to determine how reliable it is for finding gravitational lenses hidden in images from all sky surveys. This type of AI was used to find about 5,000 potential gravitational lenses, which needed to be confirmed. Using spectroscopy for confirmation, the international team has now determined the technique has a whopping 88% success rate, which means this new tool could be used to find thousands more of these magical quirks of physics.

August 3, 2022August 3, 2022 by Brian Koberlein

Astronomers Measure the Signal of Dark Matter From 12 Billion Years ago

Visualization of how dark matter lenses distant light. Credit: Reiko Matsushita (Nagoya University)

Although the particles of dark matter continue to allude us, astronomers continue to find evidence of it. In a recent study, they have seen its effect from the edge of visible space, when the universe was just 1.5 billion years old.

July 23, 2022July 23, 2022 by Andy Tomaswick

A Mission to Reach the Solar Gravitational Lens in 30 Years

NASA’s Institute for Advanced Concepts is famous for supporting outlandish ideas in the astronomy and space exploration fields. Since being re-established in 2011, the institute has supported a wide variety of projects as part of its three-phase program. However, so far, only three projects have gone on to receive Phase III funding. And one of those just released a white paper describing a mission to get a telescope that could effectively see biosignatures on nearby exoplanets by utilizing the gravitational lens of our own Sun.

June 17, 2022June 17, 2022 by Nancy Atkinson

Using the Sun as a Gravitational Lens Would Let Us See Exoplanets With Incredible Resolution

An artist view of countless exoplanets. Credit: NASA/JPL-Caltech

Have you ever seen wispy arcs and rings in astronomical images taken by the Hubble Space Telescope and other observatories? These unusual features are caused by a quirk of nature called gravitational lensing, which occurs when light from a distant object is distorted by a closer massive object along the same line of sight. This distortion effectively creates a giant lens which magnifies the background light source, allowing astronomers to observe objects embedded within those lens-created arcs and rings that are otherwise be too far and too dim to see.

A group of researchers are working on plans to build a spacecraft that could apply this quirk by using our Sun as a gravitational lens. Their goal is to see distant exoplanets orbiting other stars, and to image an Earth-like exoplanet, seeing it in exquisite detail, at a resolution even better than the well-known Apollo 8 Earthrise photo.

May 9, 2022May 6, 2022 by Paul M. Sutter

We can Probably Find Supernovae Enhanced by Gravitational Lensing, We Just Need to Look

Using the microlensing metthod, a team of astrophysicists have found the first extra-galactic planets! Credit: NASA/Tim Pyle

Gravitational lensing provides an opportunity to see supernovae and other transients much farther than we normally can. A new research proposal outlines a plan to use a comprehensive catalog of strong gravitational lenses to capture these rare events at extreme distances.

March 30, 2022March 30, 2022 by Alan Boyle

A New Record! Hubble Detects an Individual Star From a Time When the Universe Was Less Than a Billion Years Old

Gravitationally lensed image of Earendel — The star nicknamed Earendel, indicated by the white arrow, is positioned along a ripple in spacetime toat gives the image extreme magnification. Credit: NASA / ESA / Brian Welch (JHU) / Dan Coe (STScI) / Alyssa Pagan (STScI)

A star that sounds as if it came from “The Lord of the Rings” now marks one of the Hubble Space Telescope’s farthest frontiers: The fuzzy point of light, known as Earendel, has been dated to a mere 900 million years after the Big Bang and appears to represent the farthest-out individual star seen to date.

Based on its redshift value of 6.2, Earendel’s light has taken 12.9 billion years to reach Earth, astronomers report in this week’s issue of the journal Nature. That distance mark outshines Hubble’s previous record-holder for a single star, which registered a redshift of 1.5 and is thought to have existed when the universe was 4 billion years old.

The newly reported record comes with caveats. First of all, we’re talking here about a single star rather than star clusters or galaxies. Hubble has seen agglomerations of stars that go back farther in time.

“Normally at these distances, entire galaxies look like small smudges, with the light from millions of stars blending together,” lead author Brian Welch, an astronomer at Johns Hopkins University, said today in a news release. “The galaxy hosting this star has been magnified and distorted by gravitational lensing into a long crescent that we named the Sunrise Arc.”

A close look at the arc turned up several bright spots, but the characteristics of the light coming from Earendel pointed to a high redshift, which translates into extreme distance. The higher the redshift, the faster the source of the light is receding from us in an ever-more-quickly expanding universe.