New Horizons isn't just visiting Pluto; it's visiting this entire region. Whatever it finds, this will be a signal moment for planetary exploration - the capstone to our first reconnaissance of the planets of our solar system.
When the Voyager 2 spacecraft sped through the Saturnian system more than a quarter of a century ago, it came within 90,000 kilometers of the moon Enceladus. Over the course of a few hours, its cameras returned a handful of images that confounded planetary scientists for years.
Titan is Saturn's largest moon, and, until Cassini had arrived, there was the largest single expanse of unexplored terrain that we had remaining in our solar system.
Personally, I've got bigger hopes for NASA. I will stipulate it should keep putting telescopes in space so we can figure out where we fit in the universe, and it should also keep building those little robots that can and do.
By 1973, we had a space station, the Skylab, and we had multiple probes going up to planets. So, all this wonderful stuff happened in 10 to 15 years. About that time, there should have been enormous initiatives to make it affordable for people to fly in space, not just a handful of trained NASA astronauts and Russian cosmonauts.
The need for a detailed, comprehensive examination of the Saturn system became clear during the early 1980s, after the two Voyager spacecraft made flybys of the planet. These celebrated events were the opening acts in the story of humanity's exploration of Saturn.
Mars has been flown by, orbited, smacked into, radar inspected, and rocketed onto, as well as bounced upon, rolled over, shoveled, drilled into, baked, and even laser blasted.
We don't know how to identify intelligence over interstellar distances, so what we do instead is use technology for a proxy.
With any luck, by the time NASA's space probe hits Pluto, you'll be booking a spaceflight with a privately run suborbital airline.
Further ahead, I'd like to see tiny spacebots - smaller than your cell phone - travel outside our solar system to the nearest star system, Alpha Centauri. By keeping the mass of those spacebots low, we could more easily accelerate them.
I expect New Horizons will see more that Hubble cannot see.
Voyager's passage through Saturn's inner system exposed diverse moons with dynamic forces at work. Titan, Saturn's largest moon, whose surface remained invisible through its thick, ubiquitous haze, nonetheless teased observers with hints of a possible ocean of liquid hydrocarbons.
Cassini was so profoundly, scientifically successful. It's amazing to me, even, what we were able to do right up until the end.
I'd like to jump a couple hundred years into the future and work with the scientists who are getting back the first information from our probes to planets orbiting nearby stars.
We're in the space exploration business, and the outer solar system is a wild, wooly place. We haven't explored it very well.
Perhaps future space probes will be plastered in commercial logos, just as Formula One cars are now. Perhaps Robot Wars in space will be a lucrative spectator sport. If humans venture back to the moon, and even beyond, they may carry commercial insignia rather than national flags.
New Horizons is a very high-tech, small, roughly 1,000-pound spacecraft with the most powerful battery of scientific instrumentation ever brought to bear on a first reconnaissance mission.
Cassini was an international undertaking, led by NASA and the European Space Agency and designed to be, in every dimension, a dramatic advance over Voyager. At the size of a school bus, it was bigger than Voyager and outfitted with the most sophisticated scientific instruments ever carried into the outer solar system.
