It finally happened. On Tuesday, the space probe New Horizons passed by a mere 7,800 miles from Pluto, the closest encounter ever with a world that is, on average, 3.7 billion miles from Earth.
It took nine years for the very fast probe to get there, something that our 13.7 blogger Adam Frank estimated would take some 6,923 years by car "give or take a few decades."
The size of a grand piano, powered by 24 pounds of radioactive plutonium dioxide, New Horizons runs on just 200 watts of power — about the same as a powerful light bulb.
The mission has transformed a distant icy dot — hardly resolved from Earth-based telescopes, and a smeared ball even from the daring Hubble Space Telescope — into a true world, covered with remarkably complex geology, including a mysterious belt of dark disks around its equator. Even more amazing, the dwarf planet "has sent a love note back to Earth" showing an enormous heart-shaped feature on its surface. Even discounting our tendency for endearing images that have anthropomorphic meanings, it is a once in a lifetime event, capping an era of NASA-led space exploration that has taken probes to all of the major worlds of our solar system.
Distant, once inaccessible worlds are now familiar, their features and composition mapped and analyzed in great detail. All it takes is a computer with Internet connectivity to reveal their staggering beauty. NASA has compiled a beautiful collection of images in a dedicated website, which I suggest every family should share together in an after dinner activity.
The senior scientists working on the New Horizons mission grew up with vivid memories of Apollo's lunar landings. They followed the lead of the previous Cold War generation by pushing the boundaries of knowledge into the confines of the solar system, creating one of the most meaningful legacies of our generation — a testimony to what we can accomplish as we work together toward a common goal. I wonder what the children watching New Horizons' flyby will accomplish as they join the ranks of future space explorers. The probes have been there; perhaps now it is our turn.
In a very touching gesture, the New Horizons probe is carrying the ashes of Pluto's discoverer, American astronomer Clyde Tombaugh. In the canister with the ashes is an inscription from Alan Stern, the head of the New Horizons mission: "Interned herein are remains of American Clyde W. Tombaugh, discoverer of Pluto and the solar system's "third zone." Adelle and Muron's boy, Patricia's husband, Annette and Alden's father, astronomer, teacher, punster, and friend: Clyde W. Tombaugh (1906-1997)."
Tombaugh will continue his trip along New Horizons, crossing into a new frontier of the solar system beyond Pluto, carrying humanity's hopes and aspirations with him.
Marcelo Gleiser is a theoretical physicist and cosmologist — and professor of natural philosophy, physics and astronomy at Dartmouth College. He is the co-founder of 13.7, a prolific author of papers and essays, and active promoter of science to the general public. His latest book is The Island of Knowledge: The Limits of Science and the Search for Meaning. You can keep up with Marcelo on Facebook and Twitter: @mgleiser.