Behind the images

From cosmic visions to press release visualisations, we discover how those pictures came to be

Bringing the Bullet Cluster to life

“This image of the Bullet Cluster of galaxies actually provided the first direct proof of dark matter. I worked with Zolt Levay, Hubble’s image expert at the time, to create this image, and we went through a series of iterations of different colour mappings. At one time we had the X-rays in blue and the [gravitational] lensing map in pink, and it just didn’t work. So we reversed the colour scheme to be as you see it now. I don’t think we quite realised that we would be setting a standard of sorts for these types of images for years to come.” Kimberly Kowal Arcand

A last look at Enceladus

“[This was captured] during the descent into Saturn, on Cassini’s last orbit. It was just fun because on the last day we had the media there at JPL and I was going to be processing those final images. I was waiting all day for those to come down. While the media went off to watch the final signal [from the spacecraft] I actually came home and was just sitting on the couch working on the images. I sent them off to the JPL media office so they could include them in the press releases that morning.” Kevin Gill

Imagining Pluto

“I did this illustration 11 years ago and at the time we had no images, or very poor images, of Pluto and had to come up with something [for a press release]. I worked with Olivier Hainaut, one of the scientists at ESO (the European Southern Observatory), and he said we should have these ice patches. When we observed the first images from New Horizons of Pluto, I was like, ‘Yeah, it looks so close to what we have done!’ It was really cool. With most of the illustrations we make, we will very rarely have the chance to actually compare them with a direct observation.” Luís Calçada