More Than Just a Picture: How Images of Space Are Created

Space is full of mysteries, and in recent years, we’ve been treated to stunning pictures of some of the most extraordinary places in the universe. In 2019, the world got its first glimpse of something that had been thought impossible to photograph—a black hole. The Event Horizon Telescope (EHT) Collaboration unveiled an image of a supermassive black hole at the center of the M87 galaxy. Then, in 2021, they followed it up with a new version that revealed the magnetic fields around the black hole. In 2022, they captured an image of Sagittarius A, the black hole at the heart of our own Milky Way galaxy. These incredible images captivated the world, but creating them took much more than simply pointing a powerful telescope at the sky.

The Science Behind Seeing the Impossible

Seeing a black hole is no easy feat—it requires more than just a powerful telescope. The Event Horizon Telescope project needed a network of telescopes working together, essentially forming one giant telescope the size of Earth itself. This method, called very long baseline interferometry, allowed researchers to capture the incredible details we see in the images of black holes.

The project synchronized eight observatories in six different locations around the globe to operate as one cohesive unit. By capturing data at the right time and using specific wavelengths, the EHT gathered enough information to create these remarkable pictures. But capturing the data was just the beginning. It then took two years to process all that information to reveal what scientists hoped to see—like the bright ring of the accretion disk, a whirl of hot gases and energy surrounding the black hole. This was not just a pretty picture; it was the first visual evidence that black holes, until then theoretical, actually existed.

The James Webb Space Telescope: Creating Colorful Space Images

The breathtaking images from the James Webb Space Telescope are also much more than just snapshots of the universe. This powerful telescope is designed to gather more light and detect more detail than our eyes could ever see. Webb doesn’t simply “snap” a picture—it captures enormous amounts of data that get translated into an image.

The telescope is equipped with filters to detect different elements in space—such as hydrogen, infrared light, and even gamma radiation. This data is sent back to Earth, where it’s initially turned into raw black-and-white images. However, creating the final color images we see requires a lot of extra work.

To create a color picture, scientists first have to resize and compress the image. They also adjust brightness levels using mathematical functions to make sure that what we see is clear. They then remove artifacts—unwanted “noise” in the image, like stray lines or specks that aren’t part of the actual cosmic object. The stunning colors we see are usually made by combining multiple layers of data, each collected through different filters or wavelengths, into a composite that our eyes can easily understand. This layering brings out features and details that would otherwise be invisible to the human eye.

Why Space Images Look Different from Reality

If you find yourself disappointed that the space images we see aren’t exactly what they look like out there, don’t be. The universe is filled with light that our eyes can’t naturally see, like infrared or ultraviolet. The colors in space images aren’t necessarily what we would see if we were floating among the stars—they are visual interpretations of data meant to highlight different elements and help us better understand what we’re looking at. These enhanced images give us a deeper appreciation of the incredible complexity of the universe.

The pictures produced by telescopes like Webb and the Event Horizon Telescope are greater than the sum of their parts. They represent both the incredible technology that makes these glimpses possible and the human ingenuity involved in processing the information into something we can experience. Each image is a blend of data, science, and artistry, designed to take us to places we can only dream of—giving us a unique view into the wonders of the cosmos.