Maybe it's because a working model of the Mars rover is plopped in the nook of what was once a grand, ornate fireplace.
Or because the old coach house, with its loft that once stored hay, now accommodates a design for a spacecraft powered by solar sail.
Whatever the reason, the headquarters of the Planetary Society -- in a Pasadena house built by Charles and Henry Greene in 1903 -- is a study in juxtapositions.
Long the world's most tireless promoter of the search for extraterrestrial life, the group has worked out of the house, with its cobblestone columns out front, detailed woodwork, leaded glass and other Craftsman touches, for more than 20 years.
Which is why a Mars planet- scape made of plaster of Paris and painted in realistic browns and oranges, is on permanent display in a hallway nearby. And near what was once the master suite, a series of canvases depict a Russian cosmonaut floating in an oil-colored version of space.
FOR THE RECORD:
Planetary Society: An article in Friday's Section A about the Craftsman house that serves as the Pasadena headquarters for the Planetary Society said the society is asking $3.5 million for the house and two other buildings. The correct price is $2.1 million. —
There's always been a bit of irony in the fact that the organization, which is also devoted to exploring the planets, has operated out of a building constructed the year the Wright Brothers made their historic flight at Kitty Hawk.
As Susan Lendroth, the group's communications and events manager, led a visitor up a steep, twisty staircase to the second floor, she pointed to erstwhile bedrooms, now crowded office spaces, and closets and bathrooms jammed with the detritus of decades of lobbying for space exploration.
"There are three layers here," she said. "Past, present and future. The whole house is layered like that."
The Planetary Society was founded in 1980 by author, astronomer and futurist Carl Sagan; rocket scientist Louis Friedman; and Bruce Murray, then director of the Jet Propulsion Laboratory in La Cañada Flintridge.
At the time, the country's planetary program was in danger of being canceled, and the trio felt that more efforts were needed to promote planet exploration and the search for extraterrestrial life.
Since then, the group has watched as the fortunes of space exploration have shifted. Schoolchildren now breathlessly track the movements of each Mars rover. And the Cassini mission to Saturn and Titan, launched in 1997, continues to broadcast images back to Earth.
When the group moved into the Greene and Greene on quiet Catalina Avenue in 1985, they reveled in its historic details, said Friedman, now the Planetary Society's executive director. The building, moved in the early 1930s from its original location on Colorado Boulevard, had served as a private residence and a boarding house before being converted into office space.
And although the society's staff is quick to point out the original leaded-glass windows decorated in a tulip motif, for example, or the original copper sink in a butler's pantry, taking care of such an architectural gem can be burdensome, Friedman said: "The charm of something old gets old."
Exterior beams appear to be splintering. That copper sink begins to tarnish almost immediately after it's been polished.
Repair costs are estimated at nearly $1 million. So earlier this month, a for-sale sign was placed on the front lawn. The Planetary Society is asking $3.5 million for the house and two other buildings.
Friedman said the decision to sell was made over the course of the last year by the Planetary Society's board of directors -- a group that includes director Steven Spielberg, Bill Nye "the Science Guy" and PayPal founder Elon Musk, whose new company, SpaceX, is developing affordable rockets to carry cargo and people into space.
"We're pretty comfortable here," Friedman said. "But the board looked at it and thought it was a maintenance and money issue. As it begins to run down, it doesn't look so great."
Friedman said that the organization paid about $700,000 for the property in 1988 and hopes to use the proceeds to move to a space that is a bit more modern and a lot easier to maintain. "Maybe there's a better way to use our money than to tie it up in a building," he said.
He said he was hoping for a buyer who was interested in preserving the historic property. And because the group owns the buildings outright, it can afford to wait. "If we don't get a good price, we aren't going to sell," Friedman said.
For now, though, the group is concentrating on its current projects.
As Friedman sat at a table appointed with mismatched chairs in the middle of the building's old formal sitting room, he said that he feels invigorated by the ongoing work -- and the support of the group's roughly 50,000 members.
After a first attempt at launching a solar sail craft failed for a variety of political and practical reasons, the Planetary Society is getting ready to try again with a different vehicle.
Members have launched a program to advocate for the discovery of planets around other stars. And they are undertaking a project that Friedman called "novel and a bit controversial": a plan to place a sealed capsule filled with microbes on a three-year Russian mission to the Martian moon of Phobos and back. The idea, Friedman said, is to test whether living organisms can survive the trip.
And there are still a few things to explore back at home: secret touches that Greene and Greene worked into the design of the building.
In what was once the formal dining room, three women worked at hulking, computer-laden desks, and Lendroth touched a piece of wood paneling along one wall. It gave way -- yielding a child-size space that might once have been a hiding place for silver but looks perfect for a rousing game of hide-and-seek.
There's talk that an upstairs bedroom, with an octagonal window, might have once had a secret staircase leading to the building's cellar.
But even after years of tapping on walls and floors, it's a space that the Planetary Society has yet to encounter.