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Stay informed with commentary and opinion pieces on the latest issues in science, technology, health and the environment, written by expert 91av journalists and world-leading researchers and thinkers.

Physics

Could we eliminate any particles from the standard model of physics?

The standard model of physics is one of the most successful scientific theories in existence, but do we need it all? Columnist Chanda Prescod-Weinstein explores whether it’s carrying any excess baggage

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Humans

What primates tell us about the evolutionary origins of keeping pets

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Mathematics

A mathematical measure of surprise explains why we fall for clickbait

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Environment

We must adapt to climate change while also tackling the root cause

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Physics

The paradox that breaks the laws of physics | John Goold

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Physics

The once-impossible black holes that could break thermodynamics

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Health

Are beef-liver or standard iron supplements better for boosting iron?

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Technology

Why full-fledged quantum computers might always be five years away

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NGC 6357: Cosmic 'Winter' Wonderland Although there are no seasons in space, this cosmic vista invokes thoughts of a frosty winter landscape. It is, in fact, a region called NGC 6357 where radiation from hot, young stars is energizing the cooler gas in the cloud that surrounds them. This composite image contains X-ray data from NASA's Chandra X-ray Observatory and the ROSAT telescope (purple), infrared data from NASA's Spitzer Space Telescope (orange), and optical data from the SuperCosmos Sky Survey (blue) made by the United Kingdom Infrared Telescope. Located in our galaxy about 5,500 light years from Earth, NGC 6357 is actually a "cluster of clusters," containing at least three clusters of young stars, including many hot, massive, luminous stars. The X-rays from Chandra and ROSAT reveal hundreds of point sources, which are the young stars in NGC 6357, as well as diffuse X-ray emission from hot gas. There are bubbles, or cavities, that have been created by radiation and material blowing away from the surfaces of massive stars, plus supernova explosions. Astronomers call NGC 6357 and other objects like it "HII" (pronounced "H-two") regions. An HII region is created when the radiation from hot, young stars strips away the electrons from neutral hydrogen atoms in the surrounding gas to form clouds of ionized hydrogen, which is denoted scientifically as "HII". Researchers use Chandra to study NGC 6357 and similar objects because young stars are bright in X-rays. Also, X-rays can penetrate the shrouds of gas and dust surrounding these infant stars, allowing astronomers to see details of star birth that would be otherwise missed. A recent paper on Chandra observations of NGC 6357 by Leisa Townsley of Pennsylvania State University appeared in The Astrophysical Journal Supplement Series and is available online. NASA's Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program for NASA's Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, controls Chandra's science and flight operations.

Space

Why the most central law in cosmology may need to be broken

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Physics

The biggest mysteries in physics may have one answer

Could our universe have more dimensions than the three of space and one of time that we experience?

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Health

A new kind of drug will help fight previously untreatable conditions

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Health

Peptides are the latest wellness trend – but do they work?

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Environment

Getting a bit more gas from the North Sea doesn’t matter climate-wise

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Mind

How ultra-processed foods may damage your long-term brain health

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