Euclid View of Milky Way Heart Previews Core Survey by NASA’s Roman - UNIVERSE

This image by ESA’s (European Space Agency) Euclid (with color added using ground-based images) provides an earlier snapshot of a region of our galaxy that NASA’s Nancy Grace Roman Space Telescope will repeatedly observe during the upcoming years. Euclid spent one day taking a series of nine individual images near the heart of the Milky Way. Its wider image has resolution similar to Roman’s, though it’s also shallower and lacks some of the colors Roman will see. At the right of the frame, Euclid looks through the dense foreground of the Milky Way’s galactic plane, where thick molecular clouds appear as dark patches that obscure parts of the galactic bulge beyond. Toward the left, the view rises to higher galactic latitudes: the yellow glow of the bulge becomes clearer, with fewer and more isolated foreground clouds interrupting the starlight.

ESA/Euclid/Euclid Consortium/NASA, CFHT, image processing by J.-C. Cuillandre and E. Bertin (CEA Paris-Saclay)

A new look at the heart of our Milky Way galaxy by Euclid, an ESA (European Space Agency) mission with NASA contributions, overlaps with a region scientists will observe with NASA’s Nancy Grace Roman Space Telescope, launching later this summer. This sneak peek gives astronomers a major jumpstart on a core Roman survey, helping scientists learn more than they could from either telescope alone.

“This is the only time Euclid has paused its normal sky survey, which is mainly geared toward cosmology,” said Jason Rhodes, a senior research scientist at NASA’s Jet Propulsion Laboratory in Southern California. Rhodes serves as both the U.S. Euclid science lead and the NASA JPL Roman project scientist. “This takes a lot of work and planning, so it really has to be something with a high impact for science. Adding Euclid’s snapshot to Roman’s future survey will help us map our galaxy better and identify hard-to-find cosmic treasures like isolated black holes and rogue planets more easily.”

Euclid took one day out from its six-year prime mission to preview the area of sky that will be targeted by Roman’s Galactic Bulge Time-Domain Survey, which will provide one of the deepest views ever into the center of our galaxy. Though Euclid’s one-time observation is shallower and lacks some of the color detail Roman will see, it has similar resolution and covers a larger region — about 5 square degrees, or the sky area covered by about 25 full moons — since Roman’s survey area hadn’t yet been determined when the observation took place in March 2025. 

 

This artist’s concept outlines the areas of the galactic core covered by Euclid (orange) and the future survey area of the Roman telescope (green). The Euclid observations more than cover Roman’s planned survey area because the Roman coverage wasn’t yet set in stone when Euclid imaged the area. The only exception is the portion right in the galactic center since Euclid’s visible light observations can’t pierce the thick dust in this region like Roman’s infrared vision will.

NASA’s Goddard Space Flight Center

Over the course of its five-year primary mission, Roman will repeatedly image a smaller region (1.7 square degrees, or roughly the sky area covered by 8.5 full moons) to watch how hundreds of millions of stars and other objects change over short time periods. Monitoring these changes will reveal hordes of new planets, along with many other cosmic objects and phenomena. Stitching Euclid’s observation onto the front end of Roman’s collection will essentially extend the survey by two years (since Roman’s galactic bulge observations are set to begin in spring 2027), making even more science possible.

Mining hidden gems

Roman will watch for tiny surges in starlight that herald a microlensing event. This light-bending phenomenon occurs when a massive object like a star, planet, or black hole — any object with sufficient gravity — closely aligns with a background star from our vantage point. Light from the distant star curves as it travels through the warped space-time caused by the nearer object’s mass.

This image from Euclid (with color added using ground-based images) zooms in on the center of our Milky Way galaxy. The region gets its golden tone from myriad old, cool stars that have yellowish hues. Stars in this region are heavily crowded, so observing in this direction increases the likelihood of catching microlensing events.

ESA/Euclid/Euclid Consortium/NASA, CFHT, image processing by J.-C. Cuillandre and E. Bertin (CEA Paris-Saclay)

If the alignment is especially close, the nearer object acts like a cosmic lens, focusing and magnifying light from the background star.

“Most often, the lensing object is another star,” said Matthew Penny, an assistant professor at Louisiana State University, and co-lead of Euclid’s exoplanet science working group who has spent more than a decade simulating both Euclid and Roman data. “But Roman will also be able to detect planets orbiting them, and all kinds of weird objects that are nearly impossible to find any other way.”

Among those strange objects are black holes left behind after the most massive stars die. Astronomers think there should be about 100 million of these stellar-mass black holes in the Milky Way, but so far they’ve almost exclusively detected the invisible objects when they interact with a companion star. Yet most are thought to wander the galaxy alone. Roman will find them even when there’s nothing nearby to reveal their presence.

While microlensing events created by planets are typically hours or days long, black holes pack in so much mass that they can bend light over a larger region of space, creating much longer signals. That means astronomers may need to observe them for years to see the objects move out of alignment.

“The extra two years provided by Euclid give astronomers more time to watch the lens and source star drift apart, making it easier to identify the lens and measure its mass,” said Himanshu Verma, a postdoctoral researcher at Louisiana State University who has been analyzing Euclid images to help scientists predict and better understand the microlensing events Roman is expected to observe.

This image from the Advanced Camera for Surveys instrument on NASA’s Hubble Space Telescope is part of a 1.1-square-degree survey of the center of the Milky Way. Hubble’s full survey, which is made up of more than 350 individual images taken across about 14 months, is smaller but higher resolution than ESA’s Euclid observations and both overlap with the area Roman will cover. By capturing preview images years before Roman begins its microlensing search, Hubble and Euclid provide early reference points that will help astronomers measure the motions of stars and better characterize the planets and other objects Roman discovers.

Adapted from Terry et al. 2026

While most planet-hunting methods are best at finding scorching worlds tightly hugging their host star, microlensing is better at detecting worlds in orbits larger than Earth’s. That includes planets that whirl around their stars farther away than Neptune orbits the Sun and ones that have been kicked out of their original star systems altogether, now destined to roam the galaxy all alone.

“When Roman finds them, astronomers will be able to cross-reference Euclid’s earlier observations to look for stars near the lensing object, so we can confirm whether a planet is truly rogue or just orbiting very far from its host star,” said David Bennett, a senior research scientist and microlensing expert at the University of Maryland, College Park and NASA’s Goddard Space Flight Center. 

Milky Way mapping

Scientists will also pair Euclid data with Roman’s Galactic Plane Survey. This observation program will reveal our home galaxy in unprecedented detail over an area about 400 times larger than the galactic bulge survey. In one month of observations spread across two years, the Roman survey will unveil tens of billions of stars and explore previously uncharted structures.

It’s tricky to study our own galaxy because it’s like trying to map the human body from inside a cell; there’s a lot of stuff in the way. Combining Euclid’s observations with Roman’s will let astronomers watch stars slowly move across the sky. Since stars in different parts of the Milky Way tend to follow different paths, this will help astronomers figure out which part of the galaxy those stars are in.

“One of the most exciting aspects of the Euclid observations is that they give us the chance to test and improve Milky Way models,” Penny said.

Euclid’s one-day detour offers a scientific payout that will last for years and shows how much more can emerge when telescopes team up.

“We’ve shown that these two telescopes can work together to do science that surpasses what either was originally designed for,” Rhodes said. “In doing so, we’ve established a model for future coordinated observations that can unlock far more discoveries than either mission could make alone.” 

To learn more about the Roman mission, visit: https://www.nasa.gov/roman 

By Ashley Balzer - Ashley is the lead science writer for NASA's Nancy Grace Roman Space Telescope. 

Source: Euclid View of Milky Way Heart Previews Core Survey by NASA’s Roman - NASA 

Electrochemical research takes major strides towards harvesting a vital battery material - Energy & Green Tech

Former UChicago Pritzker School of Molecular Engineering graduate student Grant Hill, PhD’24, and UChicago PME Assoc. Prof. Chong Liu are behind a new paper in Nature Communications exploring a new, promising way to extract the battery material lithium from water. Credit: John Zich

The supply of lithium—the battery material that keeps digital devices humming, EVs racing and renewable energy on the grid—will not meet even half the expected demand by 2040.

Ramping up production using old methods will create new problems, including environmental damage, pollution, cost and water scarcity. Unconventional ways must be found to fill this lithium gap.

One promising solution is electrochemical intercalation. Common in the world of batteries and supercapacitors, it's when researchers apply electricity to insert ions between the layers of a different material.

Using this technique to extract materials from water creates force-fed filters, using electrical currents to pull charged lithium ions through microscopic pathways. But the pathways that let lithium ions through will also admit other ions, including the vastly more common sodium.

In new research published in Nature Communications, a team from the University of Chicago Pritzker School of Molecular Engineering (UChicago PME) was able to crack this problem. They used electrochemical intercalation to extract 99% pure lithium from a solution where the ratio of sodium to lithium was 1,000 to 1.

"Our goal is to develop materials that can selectively separate lithium from other salts," said the paper's first author, former UChicago PME graduate student Grant Hill, Ph.D."24. "For this class of materials, the main competitor is sodium, because they're just so chemically similar in charge and size."

The work reveals that the ion pathways that let lithium through layered material—in this particular research, cobalt oxide—are governed by the push and pull between two forces. This represents both an advance in pure science and a way forward for developing new, real-world extraction techniques.

"We know there are two parallel reactions that will always occur at the same time," said UChicago PME Associate Professor Chong Liu, corresponding author of the new work. "One is driven by the charge, when we put current in the material. The other one is that naturally, the materials will find equilibrium."

'The parking lot is full'

Batteries are the workhorses of the global transition off fossil fuels, but the methods used to harvest the common battery material lithium are far from eco-friendly. They require huge quantities of acid to melt roasted spodumene ore or massive brine pits to pull millions of gallons (liters) of salt water from deep under the earth and let it dry in the sun.

Battery researchers across UChicago PME are exploring ways around this problem. For the Liu Group, this means advanced materials and methods for extracting lithium directly from water.

The challenge is making sure they only extract lithium. Before they could apply electrochemical intercalation to this problem, they had to discover how materials respond when multiple ions are inserted at the same time. This co-intercalation is the real-world situation faced when extracting lithium from salty water—and a major blind spot in pre-existing research.

Liu's team first explored this class of material in a 2021 Matter paper and a 2024 Nature Materials paper.

"People might not realize the interactions could be that complicated, and that there is a phase equilibrium that's governing the ion exchange behavior," Liu said.

One major problem is lithium's downstairs neighbor on the periodic table—sodium.

Sodium ions are also a third larger than lithium ions, similar enough in size and charge to be pulled by the electric field along with lithium, but large enough to cause problems. The Liu Group's new research found sodium ions pushed the smaller lithium ions to the side of the pathway, toward lithium-friendly open sites in the material.

Hill describes the ion pathways as a highway surrounded by parking lots.

"Every lithium ion when it's starting has a lot of open sites next to it, and when the sodium is getting put in, it ends up squeezing all the lithium sites next to each other," Hill said. "For the lithium-friendly areas of the material, that parking lot's all full."

Speed limits

Overcoming this challenge required both optimizing the particle size of the lithium ions and finding a balance between two competing reactions.

The first of the two reactions is the intercalation itself, caused by the researchers using current to add ions between the layers. That's the traffic down the highway. The second is the ion exchange. As the competing sodium and lithium ions find equilibrium, the rate ions pull into the metaphorical parking lot.

Equilibrium occurs at its own rate, but the researchers can determine how quickly they pump ions in. This means they can set the "speed" of the first reaction to one of three options: faster, slower or the same as the speed of the second reaction.

"We discovered that the three regimes behave very differently, and it's only when you allow enough time to let the ion exchange catch up with the intercalation that we can have this very reversible material response," Liu said.

Slowly inserting the ions and finding the ideal particle size allowed this reversibility.

"Reversibility means that the material can repeatedly take up and release lithium without getting stuck in an undesirable state," Hill said. "By designing smaller particles that can quickly adapt to their environment, we ensure the material can reliably return to its preferred state each cycle. This reversibility allows us to keep extracting lithium efficiently over many cycles, improving both selectivity and total recovery."

Hill said the lithium cobalt oxide material the team studied is near-ideal for this kind of work. But cobalt is comparatively costly and difficult to source, with most of the world's reserves found in the Democratic Republic of Congo.

"Expanding this research to more abundant and economically friendly transition metals, especially the manganese-rich ones, would really make this breakthrough an attractive opportunity for future applications," Hill said.

Provided by University of Chicago 

by University of Chicago

edited by Robert Egan, reviewed by Andrew Zinin 

Source: Electrochemical research takes major strides towards harvesting a vital battery material