When the Smithsonian’s National Air and Space Museum opened in 1976, the planets known to science numbered just nine. Almost half a century later, the museum’s reconceptualized exhibition, “Exploring the Planets,” reflects the fact that astronomers have since confirmed the existence of thousands more outside our own solar system and are now confident the Milky Way galaxy contains even more planets than stars.

The majority of these exoplanets—more than 5,200 as of this writing—are known thanks to the Kepler space telescope, launched in 2009 and operated until the fuel supply required for the observatory to maintain its orbit was finally exhausted nine years later.

Artist's conception of the Kepler Space Telescope
NASA's Kepler space telescope (above in an artistic rendering) discovered more than 2,600 "new" planets before it was retired in 2018. Dan Rutter, Ames, NASA

Kepler discovered more than 2,600 of those “new” planets with the simple detection trick of monitoring the change in light via what is called “transit,” or what occurs when a celestial body, potentially a planet, passes between the observatory and a distant star. With this method, sky watchers can accurately estimate the object’s mass and distance from the star. When NASA announced Kepler’s retirement on October 30, 2018, the space agency celebrated an astonishing scientific achievement—confirmation of the existence of worlds, potentially even habitable ones, beyond our own solar system.

And yet for years, NASA decision makers were unconvinced the observatory would work.

The piece of gear that changed their minds, the Kepler technology demonstrator, is one of the treasures that went on view in October when the museum reopened its west-wing galleries as part of a massive seven-year building renovation. But without the placards and contextual materials that make clear the artifact’s significance, the tool doesn’t look like much.

“You can see the duct tape; you can see the wires,” says Matt Shindell, the museum’s curator of planetary science and exploration. “It’s not a clean piece of space technology like we’re used to seeing.”

Kepler technology demonstrator
The Kepler technology demonstrator played a huge role in the lead up to the discovery of thousands of unknown exoplanets. Jim Preston, National Air and Space Museum

Shindell is the figure most responsible for convincing officials at the NASA Ames Research Center in California’s Silicon Valley, to transfer this janky-looking but monumentally important artifact to the museum. In 2017, Shindell visited Ames to meet with Bill Borucki and Fred Witteborn, two of the visionary astronomers who—in collaboration with Dave Koch and Ted Dunham—built the test bed beginning in 1999 to prove to their skeptical superiors that the optics they proposed to launch into space would be sensitive enough to detect roughly Earth-sized transiting planets even with the radiation, electromagnetic activity and general “background noise” of space.

Borucki had envisioned the launching of a transit-based telescope into space since the early 1980s. To persuade their NASA bosses to fund his dream project, he and Witteborn built something not unlike a kitchen-table science project, using a laser and a charge-coupled device (CCD) camera, before the digital-imaging technology had the off-the-shelf ubiquity that it does today.

Their contraption consisted of a series of wires concealed behind a metal plate with tiny holes laser-drilled in its surface. They ran a current through the wires to make them heat up and expand to simulate the transit of the planets in front of a star.

Mars Rovers on Display
Three Mars rovers on view include, from left, the Marie Curie rover—a spare from the 1997 Mars Pathfinder mission, the surface system test bed for the Opportunity rover and the full-scale model of the Mars rover Curiosity.   Jim Preston, National Air and Space Museum

“The people who believed in this mission kept proposing it,” Shindell says. “A lot of people would’ve probably moved on after being turned down a few times. But this team really felt like this was an important mission and kept pushing to answer all the questions NASA had.”

When their CCD photometer proved capable of accurately measuring the change in diameter of the wires, NASA had the assurance it needed to begin work on a big version.

The Kepler technology demonstrator isn’t the only earthbound relative of a piece of space-flown exploration tech in the gallery. Shindell also persuaded NASA’s Jet Propulsion Laboratory in Pasadena, California, to transfer to the museum the surface system test bed for the Opportunity rover that surveyed the surface of Mars from January 2004 until June 2018.

I gave strict orders to our conservators that the dust has to be preserved with the rover 

The apparatus, now on view, is essentially identical to the Mars rover—minus the solar panels that kept Opportunity’s batteries charged. (Shindell did acquire a set of the panels, which were omitted from the display.) This robot allowed Jet Propulsion Lab engineers to work through problems here on Earth that their Mars explorer encountered and to write code that would correct the issues. Though it looks a bit naked without the solar panels, it’s still authentically… dirty.

“I gave strict orders to our conservators that the dust has to be preserved with the rover,” Shindell says. “That’s dust that came from the Mars Yard and the in-situ laboratory where they would simulate the conditions on Mars. So that simulant Mars dust, which is made from a variety of materials including diatomaceous earth and brick dust and other things” helped the engineers predict how Martian dust might interfere with Opportunity’s innards. (The Opportunity test bed is not be confused with two other rover artifacts on view—the Marie Curie rover, a spare from the 1997 Mars Pathfinder mission, complete with solar panels, and the full-scale model of the Mars rover Curiosity.)

Still on Shindell’s wish list? An engineering model of the Ingenuity Mars helicopter. “I would love to have that just sort of hovering here,” he says, smiling. The Jet Propulsion Lab has his number. “They know what I want.”

Mariner 9 Photomosaic Globe and Pluto Discovery Plates
The Mariner 9 photomosaic globe (left) is assembled from some 1,500 photographs that the probe took of the Red Planet between November 1971 and October 1972. Jim Preston, National Air and Space Museum

Back on display after a period of conservation is the photomosaic globe of Mars assembled from some 1,500 photographs that the Mariner 9 probe took of the Red Planet between November 1971 and October 1972. It was the first photomosaic made of any planetary body.

In its new location, visitors can appreciate the fine detail of the model, which was harder to see in its previous perch. And while the photomosaic globe was quickly made obsolete due to the relatively low resolution of Mariner 9’s cameras compared to the ones the Viking orbiters carried to Mars in 1975 (arriving in 1976), it remains a unique combination of high-tech and handmade, a papier-mâché project made from photographs shot by a space probe. “It is a real work of art, but also a scientific tool,” Shindell says.

Star Trek Spock ear tips and a Tribble
Actor Leonard Nimoy, who starred as Mr. Spock in the 1966-69 "Star Trek" TV series wore these ear tips, which are on view with a prop used in the episode "The Trouble with Tribbles." Jim Preston, National Air and Space Museum

Newly on display is a 1950 first edition of Ray Bradbury’s influential science fiction novel (though it was initially a collection of short stories) The Martian Chronicles, a cautionary tale about human expansion to Mars and our careless contact with the planet’s indigenous populace.

For those who prefer a more optimistic imagining of humanity’s spacefaring future, the gallery also includes a set of the foam ear tips that actor Leonard Nimoy wore on the original 1960s “Star Trek” TV series to depict the half-Vulcan physiognomy of his character Spock. While a number of such pairs were made for the show, this set comes from Nimoy’s personal collection. Before his death in 2015, the actor displayed them in his home in a box he built himself, also on view in the museum. Nimoy’s children, Adam and Julie, donated this artifact to the Smithsonian in 2021—or in Trek time, Stardate 47634.44.

The “Kenneth C. Griffin Exploring the Planets Gallery” is now on view at the National Air and Space Museum.

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