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neutron stars

Lede art for "Troubled Times for Alternatives to Einstein’s Theory of Gravity"

Troubled Times for Alternatives to Einstein’s Theory of Gravity

New observations of extreme astrophysical systems have “brutally and pitilessly murdered” attempts to replace Einstein’s general theory of relativity.

Illustration: man using rulers stacked on a compass as a telescope
insights puzzle

Solution: ‘Triangulation and Motion Sickness’

A method for estimating distances in sailing and astrophysics helps explain why riding on buses and boats can make us nauseous.

Illustration for Extreme Radio Bursts

Astronomers Trace Radio Burst to Extreme Cosmic Neighborhood

A mysterious object that repeatedly bursts with ultra-powerful radio waves must live in an extreme environment — something like the one around a supermassive black hole.

Illustration: man using rulers stacked on a compass as a telescope
insights puzzle

How Triangulation Leads to Knowledge

What does measuring distances in sailing and astrophysics have to with motion sickness?

An artist’s view of a pulsar near the center of the Messier 82 galaxy.

Galactic Glow, Thought to Be Dark Matter, Now Hints at Hidden Pulsars

A number of high-energy anomalies raised hopes that astrophysicists had seen their first direct glimpses of dark matter. New studies suggest a different source may be responsible.


Squishy or Solid? A Neutron Star’s Insides Open to Debate

The core of a neutron star is such an extreme environment that physicists can’t agree on what happens inside. But a new space-based experiment — and a few more colliding neutron stars — should reveal whether neutrons themselves break down.

Artist’s rendering of merging neutron stars.

Colliding Neutron Stars Could Settle the Biggest Debate in Cosmology

Newly discovered “standard sirens” provide an independent, clean way to measure how fast the universe is expanding.

Neutron star dancers

Neutron-Star Collision Shakes Space-Time and Lights Up the Sky

Astronomers have for the first time matched a gravitational-wave signal to a kilonova’s burst of light, observations that will “go down in the history of astronomy.”

Very Large Array, Socorro, NM
Abstractions blog

Ultra-Powerful Radio Bursts May Be Getting a Cosmic Boost

Repeating radio bursts are among the most mysterious phenomena in the universe. A new theory explores how some of their puzzling properties can be explained by galactic lenses made of plasma.