This personal voice gets at the heart of how social media function: They make people care. NASA’s probes have (or rather, appear to have) wants and desires and goals, and that makes us invested in their successes. Before social media, NASA fulfilled its Space Act mandate by getting people interested in the science and discovery of its missions. But being interested in New Horizons’ journey to Pluto is not the same as genuinely caring about the flying piece of space junk. And when we care, we share.

Another important reason NASA’s voice on social media is so effective because it’s really a symphony of different voices—meaning it uses social media the way we all do. Many of the NASA staff who operate social accounts will anthropomorphize satellites, space probes, telescopes, and rockets. But fans will be surprised to discover that they do so at their own discretion.

“We don’t try to dictate what that voice is,” said Yembrick. Oftentimes, account managers will elect to strike a similar tone to McGregor’s Phoenix lander—fun, lighthearted, enthusiastic. But others choose a more subdued tone. The Orion spacecraft (@NASA_Orion), which may someday bring human beings to Mars, is eager, but slightly more authoritative than playful, for instance. Messenger, which ended its 11-year mission by crashing into the surface of Mercury in April, went out on a sad, but resolute note:

“We’re really here to tell a story,” Townsend said. “That’s the constant in what we do.” The imagery is stunning, but it wouldn’t have nearly the same effect if its disseminators weren’t experts at adding context, developing narratives, and heightening suspense.

NASA’s army of helpers

Today, those storytellers include two other groups of people: astronauts, and NASA’s most loyal fans.

NASA astronauts started tweeting from space in 2009, when Mike Massimino (@Astro_Mike) flew aboard the last space shuttle mission to service the Hubble telescope. The agency has never compelled them to use social media and doesn’t give them formal training in it (though specialists on the ground help with spell-checking, formatting, verifying URLs, and so on). But nothing is ghost-written or embellished. All of the astronauts write their own posts and take their own pictures. ”They want to go and connect with the public,” Townsend said.

Then came Canada’s Chris Hadfield (@Cmdr_Hadfield) and his goofy antics aboard the International Space Station (ISS) in 2013. You might remember his rendition of David Bowie’s “Space Oddity,” which has 26 million views on YouTube:

Another of today’s stars is Scott Kelly, who’s currently aboard the ISS as part of his #YearInSpace.

Today, Yembrick says there are 48 astronauts on social media (33 of whom are NASA’s) and nearly all who visit the ISS are tweeting, ‘gramming, and even Vine-ing their expeditions. The human connection is key to what makes this popular: When Terry Virts shows us groundlings his view of a beautiful aurora, we’re seeing what he’s seeing in that moment.

Unsurprisingly, the agency has also attracted a throng of super-fans—groupies, if you will. And it has worked them into its social-media strategy in a savvy way.

Shortly after launching the Phoenix lander account, McGregor organized the first “Tweetup” for the account’s followers, for them to mingle with NASA staff and each other at JPL. People from all around the world applied, and all 130 slots were filled within an hour. 

The Tweetups are now called NASA Socials, and are heavily oversubscribed. Most events hold anywhere from 20 to 200 people. NASA says selection is not random: Preference is given to those who “actively collect, report, analyze and disseminate news on social networking platforms.”

But those who get in are given VIP treatment. ”The kind of access we give fans for these events are at the level of what we’d give a US senator,” McGregor said.

The groupies have become invaluable allies to NASA’s communications team. When the US government shut down for two weeks in October 2013, NASA’s public affairs office stopped operating. The alumni of the NASA Socials created the hashtag #WhatNASAMightTweet and then did exactly that, keeping NASA affairs illuminated on the web while the government went dark.

They’re also handy for another job: pest control. NASA attracts trolls who trumpet the same refrain over and over: The agency is a waste of precious taxpayer dollars and doesn’t do any good for the people here on Earth. McGregor says that she and her colleagues rarely have to engage with such trolls, because an army of volunteer space nerds willingly does that for them.

“Some people aren’t going to believe us as much as they’re going to believe members of the general public,” McGregor said. “In some ways, I think they’re able to convince the skeptics better than we ever could.”

Nonetheless, NASA is careful to tailor its web output not to its most earnest followers, but to the general public. ”You’ll never really see us use the term ‘EVA’, or extravehicular activity,” Townsend said. “We’re going to use the term ‘spacewalk,’ because that’s what everybody knows.” That isn’t just well-meaning egalitarianism: By packaging stories that it thinks the general public will be interested in, NASA knows it’s also attracting enterprising journalists who want to tap into that huge audience. “[The media] is an audience you can’t take for granted,” Yembrick said. “The media is the public. Our audience is humanity.”

The downside to having an audience of “humanity” is that serving it requires a galactic effort. McGregor said her job managing social media at JPL has her busier than she ever was as a field producer for CNN. Both Yembrick and Townsend, too, cite the sheer volume of posts, and the challenge of coordinating so many different accounts, as the two toughest parts of their jobs.

Lucky for them, the universe is an endless sea of mystery, and NASA commands its search vessel. The intrigue of space will never go away. “Even though we have a large following, those numbers seem small to us,” Yembrick said. When you have a target audience of 7 billion, there’s still a lot of room to grow.

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