Alien sunsets, shimmering rings, brilliant blasts of light that thrill the senses and fuel the imagination — astronomy is a visual science. In recent decades we’ve seen many astonishing views of exotic space vistas, thanks to unmanned robotic spacecraft. But these complex machines were built only to gather scientific data.
Now, a growing community of space-photo fanatics is finding the beauty behind the science. Using common but sophisticated software like Adobe Photoshop, combined with open access to literally millions of raw images taken by publicly funded space missions of the past and present, many amateurs are finding few technical barriers to creating stunning images. Their work shows familiar objects in a fresh light and coaxes new detail from vintage images.
The collection of old and new photos is vast. The Hubble Space Telescope alone has made more than a million observations since its 1990 launch; spacecraft at Mars, the moon and Saturn produced 120,000 new images during a typical 90-day period this year. Even terminated missions, such as the 1970s-era Mars Viking landers, have data available online, ready for tinkering.
The Planetary Society, a nonprofit group that promotes robotic space exploration, has collected some of thecommunity’s best images. Geologist Emily Lakdawalla, a senior editor and “planetary evangelist” at the society, has long worked to connect the public to the vast spacecraft image collections online.
“One thing that motivates the amateurs is to go into data sets and find the pictures that have esthetic value, not just value to explain a scientific concept,” she says. “The images you see repeated over and over on the Internet are ones that were produced for a press conference about a scientific result.” The society’s website includes detailed instructions and videos to help those who want to find images and process them into beautiful pictures. Anyone can register and upload away.
But creating a striking image, as with all good art, takes time and effort. Spacecraft often use black-and-white cameras, taking color photos by snapping three exposures through three different-colored filters. That means if you want to turn three images into a wide, colorful vista, you’ll actually need at least nine photos. It’s a manageable task from the Mars rovers, which often shoot in color while stationary. But the Cassini probe moves between each picture it takes, and so do Saturn’s moons. Depending on Cassini’s position and direction of travel, Saturn may also appear larger or smaller from image to image. That’s a lot to coordinate.
The older data sets are even trickier. “Voyager images can be pretty challenging,” says Lakdawalla. It’s not like the spacecraft was snapping digital photos — all the original images require conversions to modern formats before amateurs can work on them with today’s commercial software. Plus, the old Viking and Voyager spacecraft used analog television-type cameras, not fixed CCD imaging chips, so each frame might not be perfectly proportional to the next.
Despite the difficulties, there’s no shortage of artists in the community who take up the challenge, whether as an outlet for creative expression or a way to do some virtual stargazing from a bright city. Some take it beyond improving NASA’s images and help choose a camera’s target. The team behind the University of Arizona’s HiRISE camera, aboard the Mars Reconnaissance Orbiter, actively seeks public input on targets for its high-resolution camera. Similarly, the folks running the Pluto-bound New Horizons mission solicited help from forum members at UnmannedSpaceflight.com (run by the Planetary Society), seeking photo opportunities as the probe flew by Jupiter in 2007.
Even if they didn’t have today’s Internet in mind, scientists have always known the importance of preserving data for future generations. Take a look at what others are doing with the image legacy they left us.
[This article originally appeared in print as "Space Alchemists."]