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Photo of the sun
Abstractions blog

What Is the Sun Made Of and When Will It Die?

If and when physicists are able to pin down the metal content of the sun, that number could upend much of what we thought we knew about the evolution and life span of stars.

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.

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.

Victoria Meadows in her garden with her cockatoo.
Thinking Places

Victoria Meadows’ Earthly Visions of Alien Life

A living, breathing garden in Seattle serves as the perfect backdrop to an astrobiologist’s search for life on faraway planets.


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.

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.

Photo of mathematician Donald Richards sitting in a Pennsylvania State University classroom.

A Revealer of Secrets in the Data of Life and the Universe

The statistician Donald Richards lives to uncover subtle patterns hiding in real-world data.