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Physics

The fascinating story of the ultimate cosmic law

How do we know the speed of light – and why does it have a speed limit at all? Leah Crane explores the history of one of the most important numbers in the universe

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Space

We may have found a surprisingly nearby cluster of primordial stars

News

The best new science fiction books of November 2025

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The best new science fiction books of November 2025

Culture

CMB-S4 will use telescopes installed at the South Pole to measure variations in the temperature and polarization of microwave light across most of the sky to probe for ripples in space-time. Shown here is the South Pole Telescope. Photo: Brad Benson, University of Chicago, Fermilab

Space

The end of US support for the CMB-S4 telescope is devastating

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Satellite-filled sky

Earth

How worried should we be about noxious chemicals from dead satellites?

Features

Once Upon a Time in Space book - James Bluemel Cosmonaut Valeriy Polyakov seen in Mir?s window from Shuttle Discovery STS063-711-080 (6 Feb. 1995) --- Cosmonaut Valeriy V. Polyakov, who boarded Russia's Mir Space Station on January 8, 1994, looks out Mir's window during rendezvous operations with the Space Shuttle Discovery. This is one of 16 still photographs released by the NASA Johnson Space Center (JSC) Public Affairs Office (PAO) on February 14, 1995. Onboard the Discovery were astronauts James D. Wetherbee, mission commander; Eileen M. Collins, pilot; Bernard A. Harris, Jr., payload commander; mission specialists C. Michael Foale, Janice E. Voss, and cosmonaut Vladimir G. Titov. Page 134

Space

See the beauty of space, captured by the astronauts who experienced it

Regulars

Space

Is the universe really one big black hole?

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Do black holes exist and, if not, what have we really been looking at?

Space

Do black holes exist and, if not, what have we really been looking at?

Features

A bright star emitting streaks of light that curve outwards as the star moves across the night sky

Space

How faster-than-light explosions could reveal the universe’s secrets

Features

Geometric 3d render shower of decorative starry short lines. Digital waterfall made futuristic straight shapes with random repetition. Tears outer space falling in rays bright stars.; Shutterstock ID 1952851798; purchase_order: -; job: -; client: -; other: -

Physics

Should it be space-time or spacetime – and why does it matter anyway?

Seeking endorsements for her new book, Chanda Prescod-Weinstein finds herself staring at fundamental questions of space, time – and grammar

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Video

Inside the missions that made the moon landings possible

Video

Space

Could a huge lunar telescope be our best chance of spotting aliens?

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Space

NASA's first space photos restored in stunning detail

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Space

Why auroras are so much brighter and more easily visible recently

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