This Is How Hubble Images Are Made

As a cosmic photographer, NASA's Hubble Space Telescope has taken over a million snapshots documenting the universe. These images illustrate, explain, and inspire us with their grandeur. But how are those images taken? This video explains the answer to that question. Narrowband images highlight the concentration of important elements. Infrared images are like heat maps, helping us spot newborn stars in dark, dusty clouds and peer further back in time and space. In ultraviolet, we uncover active auroras on Jupiter and learn how young, massive stars develop. Image processors also clean up artefacts—signatures in an image that aren't produced by the observed target. As sensors age, some pixels become imperfect, returning too much electrical charge, or not enough. Artefacts can leave behind odd shapes or return images without any true black. These effects can be calibrated and removed. Other artefacts come from the dynamic environment of space. Even the best photographers get photobombed; in Hubble's case, the culprits are asteroids, spacecraft or debris trails, and high-energy particles called cosmic rays. By combining and aligning multiple observations, image processors can identify them and piece together an artifact-free image. Without processing, many Hubble images would be divided down the middle. This line, called a chip gap, is the tiny space between some camera sensors. Hubble moves slightly with each observation, allowing image processors to fill the gap and replace faulty pixels. And because there's no natural up or down in space, processors decide how to rotate and frame the image. It's a time consuming procedure. Simple images take about a week, while large mosaics, stitched together from many observations, can take a month to process. Hubble images may not be what we'd see firsthand. Instead, they are tools for understanding science at a glance, shedding light on otherwise invisible views of our universe. Credits Miranda Chabot (NASA Intern): Lead Producer Miranda Chabot (NASA Intern): Narrator Paul Morris (KBRwyle): Support Aaron E. Lepsch (ADNET): Technical Support