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Space

‘Unluckiest star’ may be trapped in deadly dance with a black hole

A star in a distant galaxy appears to have been almost torn apart in a close shave with a supermassive black hole, not once but twice 鈥� and astronomers hope to see it happen again

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Mind

Smartphone use can actually help teenagers boost their mood

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Mind

Babies group together their squeals and growls to prepare for speech

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Life

Why we can’t afford to ignore the world’s smallest freshwater bodies

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This new visualization of a black hole illustrates how its gravity distorts our view, warping its surroundings as if seen in a carnival mirror. The visualization simulates the appearance of a black hole where infalling matter has collected into a thin, hot structure called an accretion disk. The black hole?s extreme gravity skews light emitted by different regions of the disk, producing the misshapen appearance. Bright knots constantly form and dissipate in the disk as magnetic fields wind and twist through the churning gas. Nearest the black hole, the gas orbits at close to the speed of light, while the outer portions spin a bit more slowly. This difference stretches and shears the bright knots, producing light and dark lanes in the disk. Viewed from the side, the disk looks brighter on the left than it does on the right. Glowing gas on the left side of the disk moves toward us so fast that the effects of Einstein?s relativity give it a boost in brightness; the opposite happens on the right side, where gas moving away us becomes slightly dimmer. This asymmetry disappears when we see the disk exactly face on because, from that perspective, none of the material is moving along our line of sight. Closest to the black hole, the gravitational light-bending becomes so excessive that we can see the underside of the disk as a bright ring of light seemingly outlining the black hole. This so-called ?photon ring? is composed of multiple rings, which grow progressively fainter and thinner, from light that has circled the black hole two, three, or even more times before escaping to reach our eyes. Because the black hole modeled in this visualization is spherical and non-rotating, the photon ring looks nearly circular and identical from any viewing angle. Inside the photon ring is the black hole?s shadow, an area roughly twice the size of the event horizon ? its point of no return. This visualization is ?mass invariant,? which means it can represent a black hole of any mass. The size of the black hole's shadow is proportional to its mass, but so is the size of the accreetion disk, so its properties scale accordingly. Simulations and movies like these really help us visualize what Einstein meant when he said that gravity warps the fabric of space and time.

Physics

How the weird and powerful pull of black holes made me a physicist

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Environment

Don’t be fooled by El Ni帽o’s end 鈥� net zero is more urgent than ever

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Risk of bird flu outbreak in cows causing pandemic is less than feared

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Magnetic resonance imaging scan showing plaques (dark areas) in the centre of the brain of someone with Parkinson's disease

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Parkinson鈥檚 disease could be prevented by a recent tetanus vaccine

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Space

What would happen if we pulled out Mars鈥檚 iron core with a magnet?

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Technology

Can Google fix its disastrous new AI search tool?

Google's AI Overviews tool can offer impressive answers to search queries, but it will also make up facts and tell people to eat rocks. Can it be fixed, or will it have to be scrapped?

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Humans

Ancient Egyptian skull shows oldest known attempt at treating cancer

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Technology

Hackers are using AI to find software bugs – but there is a downside

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Environment

Can seaweed provide the minerals we need for clean energy?

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Asthma treated in mice using offshoot of CAR T-cell cancer therapy

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