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astrophysics

Illustration for "Why Can’t We Find Planet Nine?"
Abstractions blog

Why Can’t We Find Planet Nine?

Astronomers suspect that there’s a large planet hiding out in the distant fringes of the solar system. At a recent workshop, they brainstormed ways to coax it into view.

Photo for "The Milky Way Once Collided With Another Galaxy"
Abstractions blog

The Young Milky Way Collided With a Dwarf Galaxy

Astronomers have found stars dating from a long-ago collision between the Milky Way and another galaxy. The crash helps to explain why the Milky Way looks the way it does.

Illustration of a galaxy simulation.
cosmology

The Universe Is Not a Simulation, but We Can Now Simulate It

Computer simulations have become so accurate that cosmologists can now use them to study dark matter, supermassive black holes and other mysteries of the real evolving cosmos.

Photo of Emmanuelle Charpentier, Virginijus Šikšnys, Jennifer Doudna
Abstractions blog

CRISPR Gene-Editing Pioneers Win Kavli Prize for Nanoscience

The inventors of a “Swiss army knife” for genome editing received prestigious honors, as did pioneering scientists in astrophysics and neuroscience.

astronomy

Stellar Disks Reveal How Planets Get Made

Detailed images of disks swirling around young stars show the details of how solar systems come to be.

Illustration of a hanging mobile with "Planet 9" weighing down 2015 BP519's orbit, thus tilting it.
planetary science

A New World’s Extraordinary Orbit Points to Planet Nine

Astronomers argue that there’s an undiscovered giant planet far beyond the orbit of Neptune. A newly discovered rocky body has added evidence to the circumstantial case for it.

Photo of Large Magellan Cloud rotating clockwise.
Abstractions blog

What Astronomers Are Learning From Gaia’s New Milky Way Map

A roundup of some of the most important discoveries gleaned so far from the Gaia space observatory’s new map of the galaxy.

Lede art for "A Radically Conservative Solution for Cosmology’s Biggest Mystery": This Hubble image shows RS Puppis, a type of variable star known as a Cepheid variable. As variable stars go, Cepheids have comparatively long periods— RS Puppis, for example, varies in brightness by almost a factor of five every 40 or so days. RS Puppis is unusual; this variable star is shrouded by thick, dark clouds of dust enabling a phenomenon known as a light echo to be shown with stunning clarity. These Hubble observations show the ethereal object embedded in its dusty environment, set against a dark sky filled with background galaxies.
Abstractions blog

A Radically Conservative Solution for Cosmology’s Biggest Mystery

Two ways of measuring the universe’s expansion rate yield two conflicting answers. Many point to the possibility of new physics at work, but a new analysis argues that unseen errors could be to blame.

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

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.