The first spectacular photos of Pluto, explained by a UW Carl Sagan Fellow

Nine years, 3 billion miles, and $700 million later, we are finally getting the very first high resolution photos of Pluto, thanks to a NASA spacecraft called New Horizons.

It’s a pretty small planet &#8212 or dwarf planet depending on who you ask &#8212 about half the size of the United States. Its biggest moon is the size of Washington state and the smaller ones are the size of Seattle.

Photos: Scientists geek out over Pluto flyby

As of Tuesday, we only had one photo of Pluto and, to the delight of many, one side of of the dwarf planet appears to be decorated with a heart.

“You’re seeing an image that was downloaded late last night. The best stuff is yet to come,” said astronomer Dr. Sarah Ballard, a Carl Sagan Fellow at the University of Washington.

“So, right now, New Horizons has fixed its gaze on Pluto,” Ballard said. “It does not have the time during these crucial moments to turn back around and point its antennae towards the earth. So for 21 hours, we don’t know what’s happening.”

But we can already see some pretty interesting features of the planet.

“You can see polar ice caps on Pluto and they’re sort of a different color than the rest of Pluto,” Ballard said. “That’s probably because the ice caps are more methane rich.”

Researchers are looking for crater impacts to help them understand how old the planet it. Craters will determine if Pluto was formed during a catastrophic period of time in the solar system or a calmer period, Ballard explained.

“So all of these individual features are telling us something about Pluto,” she added.

New Horizons is not only taking photographs.

“It also has instruments to kind of taste the Pluto atmosphere,” Ballard said. “So it already has tasted some nitrogen atoms from the outer most kind of wreath-like Pluto atmosphere. So Pluto has an atmosphere.”

OK, so for those of us who don’t work for NASA, how do you send a piano-sized spacecraft into the solar system and actually get it to arrive at the correct destination nine years later?

“It’s powered by a radioactive battery cell, I think it’s plutonium,” Ballard said. “The amount of power running all of these instruments, which there is something on the order of 10, is like a nightlight. That’s about how much power. Talk about energy efficient appliances. It’s an incredible feat of engineering.”

And can New Horizons be redirected and controlled from the Earth?

“It can be controlled in part, but you have to remember that it’s many hours away with light travel time. So you can do little course corrections,” Ballard said.

New Horizons will fly between the orbits of Pluto and some of its moons.

“So they have a very, very precise orbit, which I’m sure has been refined over time as they’ve watched Pluto and its moons in the intervening weeks,” Ballard said. “So they kind of know exactly where to turn. They’re doing small little adjustments. But the big picture stuff has been planned for a really, really long time.”

Now the question we all want to know: Is Pluto a planet or not?

“Part of the reason why Pluto was dethroned from being a planet in 2006 was because there was another body found further out in the solar system called Eris, which folks thought, at the time, was larger than Pluto,” Ballard said. “So the question is, if there are things further out than Pluto that are larger than Pluto, what makes Pluto a planet and not these things? Should we then have dozens of other ‘planets?'”

Scientists confirmed that Pluto is larger than Eris, so Pluto is kind of the “King of the Kuiper belt.”

“So whether or not it should be a planet has become a question that I think folks have a really strong emotional investment in,” Ballard said. “But my major response would be, ‘should we then have dozens of other planets?’ The era of calling Pluto a planet is associated with an era of limited knowledge about the outer solar system.”

“Folks who call Pluto a planet [are] remembering a period of time when there weren’t dozens of other Plutos. So it kind of needs another name, is my humble opinion. I think ‘dwarf planet’ does a great job. [But] folks get all cranky because it has the word ‘dwarf’ in front of it.”

After its flyby, New Horizons will keep moving. If an extended mission is funded, it will go past Pluto and snap photos of the other ‘dozens of planets,’ Ballard said. But that would be several years away. Pluto is really the last “planet” from our solar system that we will see.

“It is the last major solar system body that we’re going to have images of. So there’s a reason why I’m so excited about Pluto,” Ballard said. “In all likelihood, it will be the last map, of this quality, of a new world that I’m going to see in my lifetime.”

To see new photos, as they come in over the next several days, weeks and months, and to get the latest data on Pluto, check out New Horizon’s mission page.