Over the phone, Professor Richard Gott was describing the basics of time travel. “The star Betelgeuse is five hundred light years away. So if you got in a rocket and went to Betelgeuse at ninety-nine point nine nine five percent the speed of light, it would take you five hundred years to get there and then another five hundred to get back.” The scientist spoke quickly, though with a distinct southern drawl. “Though a thousand years would have passed on Earth, you would have only aged ten years because you were moving near the speed of light. You would have traveled a thousand years into the future!”

Richard Gott is a professor of astrophysics at Princeton University, as well as an acclaimed astronomer, mathematician, physicist, space cartographer, and author of several books.  He has also had a lot of experience explaining relativistic physics to people who don’t know much about Einstein beyond E = mc², which was welcome considering that my own physics education had trailed off somewhere between classical mechanics and chucking Styrofoam-wrapped eggs off my high school’s roof. If, say, an English major were to begin experiencing pangs of remorse at having long-since fallen off the hard science bandwagon, and then subsequently decide to reconcile his scientific deficiency by discovering the true nature of the universe, in broad strokes, over the course of a week, Professor Gott would be a good person to talk to.

Gott is asked about time travel a lot, which is not surprising considering one of his best-known books is called Time Travel in Einstein’s Universe. He recalled a question he received when he was featured on NPR’s Science Friday: “Why are humans so good at traveling through space but so bad at traveling through time?”

The farthest a human being has ever traveled from home is approximately 240,000 miles: the distance from the Earth to the Moon.  It seems a laudable accomplishment, especially for a species that, in 1969, had spent much of the previous twenty-five years trying to find the best way to blow itself up.  Yet most people don’t realize that our cosmic accomplishments are not limited to travel through the three dimensions of space. Russian cosmonaut Valeri Polyakov holds the record for the longest continuous space mission—he spent fourteen months orbiting Earth in the Mir space station from 1994 to 1995. Yet, because of the relativistic implications of traveling at high speeds for long periods of time—the station was orbiting Earth at approximately 17,200 mph—Polyakov finished his mission having aged one forty-fourth of a second less than the time he was away as measured here on Earth. He had traveled a fraction of a second into the future.

A forty-fourth of a second may not seem like a lot. Yet, as Professor Gott explained, our tendency to compare miles traveled in space to years traveled in time is fallacious.  In Einstein’s equations, a year of time travel is equivalent to a light year of distance, or about 5.88 trillion miles. Neil Armstrong traveled a mere 1.27 light seconds to plant his flag on the moon. “One forty-fourth of a second in time and one point two-seven light seconds in space, you see? They’re comparable!” And so, the Science Friday question of humans’ relative inability to travel through time compared to space is based on a faulty premise. It’s not that humans are so much better at moving through space than through time. Rather, we are equally terrible at traveling through both.

I met with Professor Edwin Turner, another astrophysics department faculty member, the next day, in his office in Peyton Hall.

Currently, Professor Turner is not so much an astrophysicist as an astrobiologist. One of his research projects investigates the possibility of extraterrestrial life on tidally-heated exomoons. Moons can be tidally heated whenever they orbit close to a much larger, more massive planet, as in the case of Jupiter’s closest moon, Io. As Io orbits the gas giant, Jupiter’s tremendous gravity creates friction in the moon’s core, heating and liquefying the rock of Io’s interior and fueling the moon’s hundreds of active volcanoes. These same processes are thought to occur on Europa, Jupiter’s sixth-closest moon, warming a layer of liquid water below the moon’s hundred-kilometer-thick ice crust. Professor Turner studies this phenomenon on exomoons that orbit planets in other solar systems tens or hundreds of light years away. Admittedly, there is no proof that exomoons even exist, though Turner thinks it unlikely that our solar system is somehow the only one to develop planetary moons. He has reason to believe tidal heating could warm theoretical exomoons enough for liquid water to exist. As conventional astrobiological wisdom goes, where there is water, there might be life.

Still, Professor Turner seemed to have a grounded view of his own field. “Let’s face it, astrophysics is almost completely useless,” he stated. “It always amazes me that someone will pay you to do it.” Yet, for him, becoming an astronomer was not much of a choice. “When I was a child, I said I’d be an astronomer or drive a garbage truck.  I guess I didn’t end up in garbage collection, so here I am.”

Edwin Turner contracted polio when he was three years old, one year before the Salk vaccine became available. Today, he gets around with a cane, but when he was a small child he had to wear an assortment of orthopedic contraptions. His mother has told him how, on those hot Southern nights when he could not sleep, she would carry him onto the front lawn and lay him on a blanket. Together, they would look up into the clear summer sky and she would speak to him softly about the moon and stars until he fell asleep.

As I was leaving Professor Turner’s office, I found myself somewhere between Voyager 1 and the Oort cloud. I was standing on a map of the universe. Four feet wide and fifty feet long, it was laid out on the floor in one of the building’s corridors. Professor Gott had designed the map, and a smaller version had appeared in The New York Times in 2004.  It was scaled logarithmically; every step represented ten times the distance of the previous one.

The universe becomes more manageable when the incomprehensible distances involved are scaled away. Earth, then the Moon, the Sun, Pluto. Multiply by a thousand in three steps and arrive at Proxima Centauri, Sirius, and Vega.  It doesn’t take long to get out of the Milky Way galaxy when every step is ten times the last. The whirlpool galaxy is not much farther on at twenty million light years. Then it is only a few more steps to The Sloan Great Wall, composed of innumerable galaxies and discovered by Professor Gott himself. It is one of the largest and most distant known structures in the universe, one billion light years from Earth and over a billion across.

Gott said his universe map was the astronomical version of the famous 1976 New Yorker cover “View of the World from 9th Avenue,” by Saul Steinburg. The drawing shows the buildings of Manhattan in the foreground with the Hudson River as a blue strip behind them, followed by a narrower strip labeled “Jersey,” and then the rest of the United States as a small, flat rectangle.

Professor Turner may be right about astrophysics being useless. From an astrophysical point of view, humans are all, of course, like Steinburg’s Manhattanites. To attempt to imagine the universe is to think of something like Gott’s map, unbearably huge distances scaled to nothing and our world placed, big and bright, at the center. Yet, how is one here on Earth to even comprehend the distance of a light year? How about a billion of them? Exomoons and time-traveling cosmonauts have no place in the lives of most Earthlings.

Still, Edwin Turner has his own reasons for studying the universe. “I’ve always liked big, distant perspectives. It puts you in a different way of seeing the problems we contend with in day-to-day life… The kind of things that most people grow out of once they get out into the world to do practical things.”

I sat around in Peyton Hall for a few hours after I had my fill of the universe map. At one point, I looked up and spotted Professor Turner on his way out the door. He was walking slowly, cane in hand, stepping through Peyton’s wide, concrete arch. I thought about him as that young boy who could never be a garbage man, the pain of his paralyzed body keeping him awake on those sweltering nights. Out on the soft grass, he was comforted by his mother’s voice. Yet, I imagine there was also another sort of comfort in looking up and out into the vast cosmos extending in all directions, in the extraordinary feeling that he was very, very small.