It's hard not to be a bit dazzled by the image of Pluto released by NASA today as the New Horizons mission made its closest approach to the dwarf planet. It's the highest resolution image of our former ninth planet we've ever had, and provides unprecedented detail of Pluto's surface.
But over the next few weeks and months, reams of other data will be pouring back to Earth from the distant body. What are we looking for, and what will we gain from this mission beyond glamour shots of everyone's favorite declassified planet?
"Studying Pluto is basically studying our past," Joel Parker, a NASA research astronomer and member of the science team for New Horizons, told me over the phone. "It's kind of like doing archaeology. We want to understand where we came from. We want to understand our relationship to things that went on in the past."
Parker explained that Pluto is really the first object of its kind that we've ever closely examined and it has some unique properties that make it ideal for peering into the past. The other terrestrial planets in our solar system (Mercury, Venus, Earth, and Mars) are much more "processed" than Pluto because they've spent billions of years so close to the Sun. Pluto, however, has been "preserved" in a sense from chilling (literally) so far out towards the edge of our solar system.
"The inner terrestrial planets don't have the same mix of ingredients that they perhaps originally formed with," Parker said. "You really need to look at things that have been kept out in cold storage in the outer part of the solar system for a long period of time to really understand what things were like. It's like putting something in the freezer: it stays pretty good for a long period of time. But if you leave something out on the shelf, it changes."
But the research being done on Pluto isn't just about the past.
For a long time, Pluto was the most distant object we could detect in our solar system. Now we know it marks just the beginning of the edge: the Kuiper belt. The Kuiper belt is littered with hundreds of small celestial bodies left over from the dawn of our solar system. But Pluto is the first of these objects that we've reached, so it will provide a new perspective on the formation of the solar system, explained Simon Porter, a postdoctoral researcher on the New Horizons team. Porter was up until the wee hours of the morning helping process the glamour shot of Pluto released today.
"It's a middle planet, really," Porter said. "It's small compared to the Earth but it's much bigger compared to everything in the asteroid belt. Pluto is the closest but there are a whole bunch of objects like this that we've discovered in the Kuiper belt. This will help us learn about what's out there, as well as how they formed."
Understanding how our solar system formed, and what this new class of celestial bodies is like, will help us in our exploration of the rest of the universe and in our quest to find other Earth-like planets, Parker added.
"You could then maybe extrapolate to ask: are there places in other parts of the universe that formed in a similar way and could perhaps have life there as well?" Parker said.
There are multiple, highly-sensitive instruments aboard New Horizons that will answer these questions for researchers. An infrared imager and spectrometer maps the color, composition, and temperature on the surface. An ultraviolet imaging spectrometer analyzes the composition of Pluto's atmosphere, while also checking for signs of atmospheres on Pluto's moon Charon and nearby Kuiper belt objects. A radiometer also helps measure the composition and temperature of the atmosphere. A telescopic camera take rad images while also providing a close observation of Pluto's geology. A solar wind and plasma spectrometer looks at how Pluto interacts with the solar wind. An energetic particle spectrometer measures how much and what kind of plasma is escaping from Pluto's atmosphere. And a dust counter (designed, built, and operated entirely by students) measures, well, dust in the solar system.
These instruments don't all produce stunning photos for us to ooh and ahh over (Parker joked that these other instruments produce more "squiggly lines" than images), but in some ways they're even more essential to understanding Pluto, our solar system, and what other objects might lie beyond.
And to be fair, those pretty pictures aren't just for space nerds to ogle, either. The high-resolution images help researchers to map the surface of Pluto and study its geology and its geography, Parker said. The much-noted "heart-shaped" surface feature, for example, is suspected to be a giant nitrogen ice field and it's something we couldn't even see from further away. The fact that the images are stunning is just an added bonus.
The encounter with Pluto could have even further ramifications beyond science, at least according to space historian Dwayne Day. In an essay for The Space Review, Day argued that the ripple effect of this encounter could affect everything from pop culture to politics back home on Earth.
"It is doubtful that Ridley Scott would be currently filming The Martian if the Curiosity rover had not spectacularly set down on Mars in 2012," Day argues. "So maybe a few years from now we'll have a movie about a human mission to Pluto in addition to all those documentaries currently in production."
He also argued the mission's success could even improve global opinions of the US, since it's a NASA mission, and new findings could change the direction of research for astronomers around the world. We're going to get so much more from Pluto than a photo and a gif. Never underestimate a dwarf.