“You’ve been lied to by textbooks that have to squeeze the Earth and the Moon into the same page,” exhorted astrophysicist and director of the Hayden Planetarium, Neil deGrasse Tyson (Figure 7-4), during his packed SXSW 2014 keynote presentation. He made this comment to a volunteer from the audience who was trying to figure out how far away to stand with a model of the Moon in relation to Tyson, who was holding a beach ball Earth.
Figure 7-4. Neil deGrasse Tyson during his packed SXSW 2014 keynote speech (photo by Hunter Whitney)
The brave volunteer stood a foot away from deGrasse Tyson — far too close. He noted that in our schoolbooks, the Moon is shown extremely close to Earth, but added there’s a practical reason for this representation. If the scaled images were shown properly, he said there’d be about an eight-page gap between the two bodies. Even as we move away from static, paper-based representations of the cosmos, there are still challenges for practically conveying appropriate senses of scale and distance as well as the ability to move from large to small while maintaining context.
From the subatomic to the galactic, the range of scale needed to think about the universe is vast. So too, representing the way the brain works requires thinking in terms of big shifts in scale from the molecular to the anatomical. Familiar frames of reference can help users maintain orientation, even in extremely large information spaces.
Randal Jackson is the manager of Internet communications at NASA’s Jet Propulsion Laboratory. Figure 7-5 shows an interactive visualization called “Eyes on Exoplanets,” for which Jackson says a primary goal was to give the general public a way to understand the growing database of exoplanet discoveries (http://eyes.nasa.gov/exoplanets). “We want lay users to develop a sense of the scale of the deep space 'search bubble’ for exoplanets within 10,000 light years of our solar system,” he says. To ensure that viewers would not get lost in space, the interface offers navigational frames of reference including a label for our sun and a “Home button for Earth.” With almost 1,600 exoplanetary systems in the database, the interface lets people see how long it would take to get to each system by automobile traveling at 60 miles per hour. For one star he randomly selected, it would take about five billion years. If you conceptually traveled by commercial jet, the journey would last around 528,000,000 years. At the unachievable rate of light speed, it would take only 473 years. The strategy is to relate things to a familiar context. Another way the interface allows for this is that for every exoplanetary solar system, the user can compare the size of it with out solar system as an overlay. Jackson says the visualizations are powered by NASA’s Exoplanet Archive — the same database that the scientists use as the official repository. The key for creating the public interface, he says, is “filtering for the data that we believe lay users would find the most interesting and relatable.”
Figure 7-5. NASA’s “Eyes on Exoplanets” interactive visualization tool