clock menu more-arrow no yes
The Gaia spacecraft has been tracking the positions of billions of stars in the Milky Way.
ESA

A mesmerizing new atlas of the Milky Way has 1.7 billion stars in it

And that’s just a tiny fraction of the total number of stars in the galaxy.

This is what happens when you shoot an incredibly high-resolution, 1 billion-pixel camera into space and instruct it to take a photo of every single star it can see.

The image above (and an easier-to-scan version below) was produced by Gaia, the European Space Agency craft, whose mission is to produce a detailed three-dimensional map of the stars our galaxy. And it is truly the largest 3D star atlas ever assembled.

Gaia’s latest map (click to find a very cool interactive version), released Wednesday, includes 1.7 billion stars. That’s around 700 million more than its last update in 2016. When you look at those stars, you’re looking at untold numbers of planets, moons, asteroids, and comets clutched within their orbits.

This database is not just for making pretty images. It also contains information on the distance, motion, and color (useful in determining temperature and age) of about 1.3 billion of the stars. It’s a 3D, moving atlas of the Milky Way.

Building such a tool is more difficult than you might imagine. Since the Earth is constantly moving around the sun, the apparent location of stars also changes throughout the year and needs to be controlled for. For some stars, “the level of precision equates to Earth-bound observers being able to spot a Euro coin lying on the surface of the Moon,” the ESA says in a press release.

ESA

Gaia uses a super-powerful camera and two telescopes to pinpoint the exact location of every star in the sky (by making around dozens of observations of each star). It then tracks information about each star’s brightness, size, and temperature.

The Gaia database also includes information on asteroids, nearby galaxies, and the surface temperatures of 100 million stars. And astronomers can use it to study how the cosmos moves, make observations about how the galaxy formed, and potentially even find new planets.

But the map is still not complete. There are likely more than 100 billion stars in our galaxy. The ESA is hoping to collect data on 2 billion stars by 2022.

You can access the entire database here. And here, find an interactive map of all the stars.

And if you have one of those VR attachments for your smartphone, you can immerse yourself in a 360-degree window into the cosmos, built from the Gaia data set.

Gaia is not the only project to map the cosmos in absurd detail

There are several such projects that are all producing dazzling results.

Here’s one to really make you feel small: the Sloan Digital Sky Survey III, a digitized atlas of the known universe. The full survey, which was released in 2016, charts a total of 1.2 million galaxies in three dimensions. That means it shows not just their locations in the sky but their distance from Earth as well.

Below is one image distilled from the survey. Each of these 48,741 dots represents a galaxy. Each galaxy is a collection of billions of stars. The stars themselves trap untold planets, asteroids, and possibly even life in their gravitational clutches. This image is just one-twentieth of the night sky, a mere pinprick of a window into the universe.

Daniel Eisenstein and the SDSS-III collaboration. Here’s a huge, high-resolution version.

Want to feel even smaller? Further reading.

Recode

Startups are betting on a psychedelic gold rush

Science & Health

Why Merck’s Covid-19 pill molnupiravir could be so important

Explainers

A better way to legalize marijuana

View all stories in Science & Health

Sign up for the newsletter The Weeds

Understand how policy impacts people. Delivered Fridays.