James' World 2

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An atom is best visualized as a tight, dense nucleus surrounded by buzzing, orbiting electrons. This picture immediately leads to a question: How do electrons keep whirling around the nucleus without ever slowing down? 

This was a burning question in the early 20th century, and a search for the answer ultimately led to the development of quantum mechanics (opens in new tab) itself.

In the early 20th century, after countless experiments, physicists were just beginning to put together a coherent picture of the atom. They realized that each atom had a dense, heavy, positively charged nucleus surrounded by a cloud of tiny, negatively charged electrons. With that general picture in mind, their next step was to create a more detailed model.

In the earliest attempts at this model, scientists took their inspiration from the solar system, which has a dense “nucleus” (the sun) surrounded by a “cloud” of smaller particles (the planets). But this model introduced two significant problems. 

For one, a charged particle that accelerates emits electromagnetic radiation. And because electrons are charged particles and they accelerate during their orbits, they should emit radiation. This emission would cause the electrons to lose energy and quickly spiral in and collide with the nucleus, according to the University of Tennessee at Knoxville (opens in new tab). In the early 1900’s physicists estimated that such an inward spiral would take less than one-trillionth of a second, or a picosecond. Since atoms obviously live longer than a picosecond, this wasn’t going to work.

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Our knowledge of atoms was changed forever when quantum mechanics peeked inside. (Image credit: Rost-9D via Getty Images)

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We live in a strange universe filled with unexplained phenomena that have perplexed humans since time immemorial. Scientists have pieced together a rough guide to the cosmos—known as the Lambda cold dark matter model (ΛCDM), or more simply, the standard model of cosmology—but many mysteries don’t seem to fit into this otherwise well-corroborated framework, especially as our view of space has gotten ever more precise in recent years.

Scientists are now especially preoccupied with intractable tensions that have emerged from different measurements of two cosmic properties: The rate at which our universe is expanding, known as the Hubble constant (Ho), and a value called sigma-8 (σ8), which describes variations in how matter clumps together across large cosmic scales.

Efforts to measure these properties in space have puzzlingly returned different values. When the Hubble constant is measured based on observations of brilliant stars that act as yardsticks in space, its speed is clocked as about 50,400 miles per hour per million light years. However, when it is measured using the cosmic microwave background (CMB), the oldest light in the universe, it is 46,200 miles per hour per million light years. Meanwhile, the value of sigma-8 is different when measured using the CMB, compared to other observational techniques.

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Cartwheel galaxy cat

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The Universe, truly, is full of wonders, and the James Webb Space Telescope has just given us our best views of one of them yet.

The object in question is a star around 5,600 light-years away, and Webb’s infrared eye has picked out an extraordinary detail: it’s surrounded by what appear to be concentric rings of light radiating outward.

While Webb’s characteristic diffraction spikes are not ‘real’, those concentric rings are – and there’s a wonderful and fascinating explanation for them.

The star is actually a binary pair of rare stars in the constellation of Cygnus, and their interactions produce precise periodic eruptions of dust that are expanding out in shells into the space around the pair over time.

These shells of dust are glowing in infrared, which has allowed an instrument as sensitive as Webb’s MIRI to resolve them in exquisite detail.

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James Webb Space Telescope’s new image of the spectacular nebula around WR 140. (JWST/MIRI/Judy Schmidt)

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The James Webb Space Telescope captured mysterious concentric rings around a distant star that astronomers are still working to explain. 

The image, taken in July, was released on Twitter by citizen scientist Judy Schmidt, prompting a torrent of comments and head-scratching. It shows a star known as WR140 surrounded by regular ripple-like circles that gradually fade away. The circles, however, are not perfectly round, but have a somewhat square-like feel to them, prompting speculations about possible alien origins. 

“I think it’s just nature doing something that is simple, but when we look at it from only one viewpoint it seems impossible, at first, to understand that it is a natural phenomenon,” Schmidt told Space.com in an email. “Why is it shaped the way it is? Why is it so regular?”

Mark McCaughrean, an interdisciplinary scientist in the James Webb Space Telescope Science Working Group and a science advisor to the European Space Agency, called the feature “bonkers” in a Twitter thread. 

“The six-pointed blue structure is an artifact due to optical diffraction from the bright star WR140 in this #JWST MIRI image,” he wrote. “But red curvy-yet-boxy stuff is real, a series of shells around WR140. Actually in space. Around a star.”

He noted that WR140 is what astronomers call a Wolf-Rayet star, which have spat much of their hydrogen into space. These objects are also surrounded by dust, he added, which a companion star is sculpting into the strange shells.

Astronomers will know more soon thanks to a scientific paper currently under review about this mysterious phenomenon. 

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The James Webb Space Telescope captured the star WR 140 surrounded by strange concentric shells. (Image credit: NASA/ESA /CSA /Ryan Lau /JWST ERS Team /Judy Schmidt)

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