New technology brings Mars to Evanston

Joanna Allerhand

A small room tucked away on the second floor of Northwestern’s library has the capacity to take a student out of this world with a pair of glasses.

NU’s Visualization Lab created a 3-D tour of the surface of Mars with pictures taken by robots sent to explore the planet.

Professors in the physics and astronomy and geological sciences departments bring their students to the Vislab to add another dimension to what they are learning in the classroom.

“I regard them as one of the hidden gems of NU,” said Andrew Rivers, a physics and astronomy lecturer who incorporates Vislab trips into his classes.

Rivers teaches introductory astronomy classes and uses the tour to expand on discussions about current Mars research, including the search for life. The tour also provides visuals for concepts that are difficult to convey in a typical classroom, he said.

“When you see the images in 3-D in person, you actually feel like you’re there and there’s a connection,” said Doug Roberts, who helped design the Mars tour.

The photos came from the two NASA rovers on Mars. Spirit and Opportunity are robots sent to help scientists better understand the history of the red planet and to search for evidence of water.

Each rover is equipped with four sets of cameras that are capable of capturing both a right- and a left-eye view of every image. One of the cameras also has a color wheel, allowing scientists to approximate the colors they would see if they set foot on Mars, Roberts said.

Images were sent directly to the Vislab during the rovers’ first two years on Mars. The right views were then matched with the left views and stitched together with software, Roberts said.

To make the surface of Mars appear 3-D, the Vislab uses two projectors, one for each side of the view. And unlike a typical slide show, the screen is silver and the audience must wear special glasses.

The technology has been around for a while, Roberts said.

“We are unique in saying it’s a mature technology now and (in) using it,” he said.

The practice of using side-by-side images is called stereoscopic imaging. It works because of the way the eyes send signals to the brain. Under normal conditions, the right eye sees a slightly different perspective than the left eye and the brain uses the difference between the two to determine how far away an object is.

This effect of depth can be recreated in the lab by placing the left-side view next to the right-side view. The brain brings them together and creates an illusion of depth.

The other key to making images appear 3-D involves eliminating unwanted light. Ordinary light waves in a room are traveling in many different overlapping pathways. Light waves must be sorted, or polarized, so only the light traveling along select pathways is let through. The light is filtered as it comes out of the projectors and again through the glasses worn by audience members.

Rivers plans to apply the same technology used for the Vislab’s tour of Mars to take his cosmology students on a tour of the universe. The information is already available and the program can be run on a personal computer. But it can’t do it in 3-D, Rivers said.

Using the Vislab, students would be able to move forward and backward and visualize what things are where, he said.

Reach Joanna Allerhand at

[email protected]