NASA’s SPHEREx Telescope Sees Menagerie of Brown Dwarfs

As it maps the sky, NASA’s SPHEREx telescope is finding thousands of brown dwarfs hiding in the dark. A selection is shown in this collage of observations, listed by spectral type, distance, and temperature in degrees Kelvin.

Zafar Rustamkulov/NASA/JPL-Caltech

NASA’s SPHEREx (Spectro-Photometer for the History of the Universe, Epoch of Reionization, and Ices Explorer) space telescope is shedding light on brown dwarfs, celestial objects that blur the line between stars and exoplanets. New findings published in The Astrophysical Journal show that these dark and cloudy worlds have chemically rich atmospheres not unlike the giant planets in our own solar system. 

First discovered in the 1990s, brown dwarfs form from collapsing clouds of gas, like stars do, but they aren’t hefty enough to sustain hydrogen fusion in their cores. These dimly glowing balls of warm gas also share characteristics with Jupiter and Saturn. In contrast to most planets, however, brown dwarfs drift in darkness, ungoverned by a host star and heated entirely from within.

“They’re kind of goth,” said Zafar Rustamkulov, lead author of the new study and a scientist at IPAC, Caltech’s science and data center in Pasadena, California. “Unlike exoplanets, free-floating brown dwarfs are completely independent celestial objects that will fade into eternity alone. We’re still learning how complex they are.”

Untold numbers of brown dwarfs roam the cosmos, like the one in this artist’s concept. But only a few dozen have been studied in detail with space-based telescopes. With the help of NASA’s SPHEREx, scientists are in the process of analyzing thousands more.

NASA/JPL-Caltech

Only a few dozen of these “dark wanderers” have been studied in detail with space-based telescopes. Astronomers want to observe more of them in the wild because much of our understanding of their makeup, storminess, and evolution comes from theoretical models.

Enter NASA’s SPHEREx, an infrared space telescope launched in March 2025 and managed by the agency’s Jet Propulsion Laboratory in Southern California.

The study authors analyzed SPHEREx observations of 37 nearby brown dwarfs spanning the full brown dwarf temperature range, from about 4,000 to minus 10 degrees Fahrenheit (2,200 to minus 20 degrees Celsius). The telescope measures their brightness in 102 different colors, from the deepest red our eyes can see, to the invisible heat of infrared light, creating a spectrum. These spectra revealed to the study authors chemically rich atmospheres harboring water, carbon dioxide, carbon monoxide, and methane.

“We’re seeing the signatures of these molecules and how they change from object to object across the entire temperature regime,” said study coauthor J. Davy Kirkpatrick, a scientist at Caltech’s IPAC. “Our paper concentrated on just three dozen, but we have thousands more that we are in the process of analyzing. I really want to see what bounds the universe places on the variety of brown dwarfs.”

“From orbit, SPHEREx sees wavelengths of light that are basically impossible to see with telescopes on the ground because water in Earth’s atmosphere absorbs them,” Rustamkulov said. “We are picking up light from the deep, red clouds of brown dwarfs all over the sky.”

Sweet spot

Spotting brown dwarfs is something of a side project for SPHEREx. The space telescope takes about 3,600 unique images per day to stitch into maps of the entire sky. Knowing where hundreds of millions of galaxies are distributed across the cosmos will help scientists reconstruct what happened in the first billionth of a trillionth of a trillionth of a second after the big bang. As it scans the sky, the telescope also is searching for the chemical ingredients of life and finding interstellar ice that could one day seed oceans on distant worlds.

For years, brown dwarfs have been spotted by other observatories, including NASA’s James Webb Space Telescope and retired Spitzer Space Telescope. But thanks to its spectral coverage, SPHEREx is now imaging thousands of them for the first time in a fruitful region of the electromagnetic spectrum that spans deep red and infrared wavelengths of light.

Thanks to its spectral coverage, NASA’s SPHEREx is revealing molecules like methane (CH4), carbon dioxide (CO2), and carbon monoxide (CO) in brown dwarf atmospheres. The telescope’s view of three different brown dwarfs appears on the left; the depictions on the right imagine them as Jupiter-like worlds.

Zafar Rustamkulov/International Gemini Observatory/NOIRLab/NSF/AURA, M.H. Wong (UC Berkeley) et al. Acknowledgments: M. Zamani

At those wavelengths, molecules carve out distinct absorption patterns in the light shining out to space. The patterns change as brown dwarfs grow older and colder. Some of the brown dwarfs observed by SPHEREx are in a dynamic stage of life when their exotic clouds thin out, giving way to methane-rich atmospheres.

“The state-of-the-art models are capturing the general chemical trend, but when it comes to these cloudy transitions, the models are struggling to match the data,” said Rustamkulov. “No two brown dwarfs are alike. Even at the same temperature, their spectra look quite distinct.”

“The findings are a call to action to explore even more of these dark worlds,” said Kirkpatrick. “This journey has turned many of us into accidental meteorologists. We know how hard it is to predict weather on our own planet, and we realize it’s going to be just as challenging to explain the phenomena we see in these bizarre, cold objects.”

More about SPHEREx

The mission is managed by JPL for NASA’s Astrophysics Division within the Science Mission Directorate in Washington. The telescope and the spacecraft bus were built by BAE Systems. The science analysis of the SPHEREx data is being conducted by a team of scientists at 13 institutions across the United States and in South Korea and Taiwan, led by Jamie Bock, principal investigator, who is based at Caltech with a joint JPL appointment, and by JPL’s Olivier Doré, the project scientist. Data is processed and archived at IPAC at Caltech in Pasadena. Caltech manages JPL for NASA. The SPHEREx dataset is freely available to scientists and the public.

For more information about the SPHEREx mission visit: https://science.nasa.gov/mission/spherex/ 

Source: NASA’s SPHEREx Telescope Sees Menagerie of Brown Dwarfs - NASA   

Nobel Prize in Chemistry 2026: How Two Chemists Taught Molecules to Amplify Their Own Handedness

Your hands are mirror images of each other, yet you cannot put a left glove on a right hand. Many molecules behave the same way, and in medicine that difference can decide whether a drug heals or harms. This year’s Nobel Prize in Chemistry honors two researchers who showed how chemists can steer reactions toward just one of the two mirror-image forms.

The announcement

On October 7, the Nobel Assembly at the Karolinska Institute announced that Henri Kagan, of Paris-Sud University, and Kenso Soai, of Tokyo University of Science, share the 2026 Nobel Prize in Chemistry. The citation reads “for the discovery of non-linear effects and autocatalysis in asymmetric organic synthesis.”

Why mirror images matter

Molecules that are non-identical mirror images are called enantiomers, and the property is known as chirality. Life is strongly one-handed: natural amino acids and the sugars in DNA each occur in essentially one form. That means the two mirror versions of a drug can act very differently in the body. The standard cautionary example is thalidomide, whose mirror-image form was linked to severe birth defects in thousands of children in the 1960s. A caveat worth knowing: later research on thalidomide’s chirality is more nuanced than the simple story suggests, so the case is best read as an illustration of the stakes rather than a full explanation.

The idea has deep roots. In 1857, Louis Pasteur let bacteria ferment the two forms of tartaric acid and found they favored only one, an early sign that biological chemistry is chiral. For decades afterward, ordinary lab reactions gave chemists an even 50:50 mix of both forms. Early in the 1900s, Willy Marckwald used a catalyst to tilt the balance very slightly, and later Nobel-winning work built reactions that produced a large excess of one form.

What Kagan and Soai added

Kagan: non-linear effects. Kagan studied the catalysts themselves. In the mid-1980s he reported that using a catalyst made of a mixture of its left- and right-handed forms could, surprisingly, enrich one form of the product more than a simple proportional calculation would predict. This is the “non-linear effect” in the prize citation.

Soai: autocatalysis. In 2003, Soai described a reaction in which the product makes more of itself. A small excess of one handed form was amplified until it made up almost 99.99 percent of the product, according to The Scientist’s summary.

Heiner Linke, chair of the Nobel Committee for Chemistry, called the prize one about foundational chemistry. In his description, Soai’s reaction spontaneously creates only one mirror image, without help from other chiral molecules, which he said had not happened since the processes that gave life its handedness billions of years ago.

Why it matters beyond the lab

The practical payoff is purer products. Understanding how chirality amplifies itself helps chemists optimize reactions to make just the desired form, which is relevant for pharmaceuticals, agricultural chemicals, flavors and scents. Dawn George of CAS, a division of the American Chemical Society, told The Scientist the work gave chemists a stronger foundation for making chiral drug molecules.

One limit to keep in mind: Soai’s reaction is a striking demonstration of the principle, but it is a specific laboratory system.

Sources and further reading

·         Original news article: Chemistry Nobel Prize for Asymmetric Organic Synthesis, The Scientist

·         Official Nobel Prize page for the laureate: Henri Kagan, facts, NobelPrize.org

·         Original paper (Kagan): Puchot C, et al. Nonlinear effects in asymmetric synthesis. Examples in asymmetric oxidations and aldolization reactions. J Am Chem Soc. 1986;108(9):2353-2357.

·         Original paper (Soai): Sato I, et al. Amplification of chirality from extremely low to greater than 99.5 % ee by asymmetric autocatalysis. Angew Chem Int Ed Engl. 2003;42(3):315-317.

Source: Nobel Prize in Chemistry 2026: How Two Chemists Taught Molecules to Amplify Their Own Handedness