This dome at the Mount Wilson Observatory houses the telescope that Edwin Hubble used to change our view of the universe. (Joel Achenbach/The Washington Post)

Steve Padilla rides an elevator to the top of the 150-foot solar tower telescope. It’s not really an elevator — it’s more like an open-air bucket, raised and lowered by cables. This is not modern machinery.

The solar tower has been operating since 1912. Everything here at the Mount Wilson Observatory is vintage — or you could just call it old. This was once the most famous observatory in the world, but now it is a virtual museum, the astronomy world’s musty attic.

Padilla is 66 and lives alone on this mountain, which rises a mile above Pasadena. He rides to the top of the tower to open the dome. Back on the ground, in the control room, he studies the reflected image of the sun — and draws sunspots.

Padilla is single-handedly maintaining a century-long tradition of continuous sunspot observations on Mount Wilson. He has no understudy.

“We’ve been doing these now for 100 years,” he says. “If I wasn’t around, I don’t know who would do them.”

This is a popular month for the sun. The Great American Eclipse of 2017, on Aug. 21, will entrance millions. Padilla, for his part, will trek to Oregon to be in the “path of totality,” where the sun is completely blocked by the moon. Scientists across the breadth of America will study the sun’s mysteriously hot corona as the moon’s shadow rolls across the continent.

The sun is scientifically intriguing and obviously essential to life on Earth — which is why there are solar telescopes around the world and in space, why the United States is building a massive solar telescope on the island of Maui, and why NASA spends close to $700 million a year on heliophysics.

And yet it’s easy for an old solar telescope to get lost in the shuffle. There are three vintage solar telescopes on Mount Wilson, which is dominated by the 150-foot tower. But they’re not cutting-edge devices and do minimal science. They’re like movie stars who have aged out of the best roles.

(Joel Achenbach/The Washington Post)

With eclipse mania sweeping the country, this is an appropriate time to ponder the history of solar astronomy. A lot of it happened right here. On Mount Wilson in 1908, astronomer George Ellery Hale obtained groundbreaking images of solar flares and vortices.

This happened in an era when the basic nature of the sun — “the star in our backyard,” as astronomer Cindy Hunt puts it — was just coming into focus. Atomic theory, still being developed, led to the realization that the sun is not on fire. It’s a giant nuclear fusion reactor.

Which is why we’re here. A fusion reactor is efficient. The sun can shine for billions of years, plenty of time for life to evolve and maybe, with the right twists and turns, produce a species that includes astronomers.

‘Best-kept secret’

The mountaintop is serene. The metropolis below is completely out of earshot. Birds flit among the oaks and pines.

“The best-kept secret in Los Angeles is where Mount Wilson is,” says Tom Meneghini, 70, the director of the Mount Wilson Institute.

To get there by car you have to take a narrow, winding road that’s not for the faint of heart. Meneghini says his wife rarely makes the drive with him, and a reporter riding shotgun can understand why — you’re never far from a cliff in the San Gabriel Mountains, which were thrust violently skyward amid the collision of tectonic plates.

Hale leveraged the wealth of steel magnate Andrew Carnegie to build an array of telescopes on Mount Wilson in the first years of the 20th century.

“This was the hub of solar astronomy for a long time,” says Hunt, who works at the Carnegie Observatories in Pasadena.

The Carnegie Observatories today does its astronomy on mountains in Chile. In 1986 it turned over operation of the Mount Wilson telescopes to the nonprofit institute now run by Meneghini.

He had spent much of his life running commercial fishing boats in the South Pacific. For the past 15 years he’s been bounding around Mount Wilson, much like a kid with a lot of cool toys. He’s a volunteer, with an institute identification badge that says “Galactic Overlord.”

The institute sponsors lectures and stargazing nights. Students can use the telescopes. Researchers can rent the hardware for a night. The goal is to keep the lights on, even if the serious astronomy community no longer seems to want these historic telescopes.

“There’s nothing we won’t try,” Meneghini says. “I don’t want to see it fail.”

Inside one small dome is a beautiful, vintage refracting telescope with an exquisite lens. Meneghini says reverently, “It’s a Brashear — those are as rare as chicken teeth.”

The great white dome houses the Hooker telescope, which was named for a benefactor.

This is hallowed ground for astronomy.

“Oh, if the walls could talk,” Meneghini says he switches on the lights in the dome. We go up metal stairs, past a telephone that surely dates to the era of silent movies. Then we’re on the main floor with the telescope, which is the size of a school bus. The mirror has a diameter of 100 inches, and it weighs 9,000 pounds.

The reflected image of the sun shines down through the tower of the 150-foot solar telescope on Mount Wilson. (Joel Achenbach/The Washington Post)

We go around the telescope and then far below, to a realm of giant gears and, as Meneghini points out, “100-year-old solenoids and relays and wiring.” The visitor might initially think that someone had done an amazing job of restoring the place to its original, vintage feel. More likely, nothing here has ever changed.

“It’s like an old stove — it dies in pieces,” Meneghini says. Be careful not to get grease on your clothes, he adds.

He opens the dome, a noisy process. He tips the telescope forward so we can view the immaculately polished mirror.

In 1919, a young astronomer named Edwin Hubble showed up to work here, and with the 100-inch he began studying the light from what were then called nebulae.

Orthodoxy held that these nebulae were relatively close. Hubble and his collaborators discovered that they were tremendously far away — indeed, they were separate island universes. Galaxies.

Then he discovered that they were receding from us — that the light was red-shifted, increasingly with distance. Behold the expanding universe.

These discoveries ensured that the 100-inch Hooker telescope would be forever famous among astronomers. But the field of astronomy can be rather coldhearted about old telescopes, particularly when they’re perched above a burgeoning metropolis that’s polluting the night sky.

‘Einstein was here’

The sun is setting, and in the control room of the 150-foot solar tower, Padilla presses buttons to guide the telescope as it follows the sun toward the horizon.

Everything about this place screams 1970s. There are racks of reel-to-reel tapes in the office. The main computer is a 1973-vintage Raytheon, and when it failed a few years ago, no one could fix it. Black-and-white photos on the walls show the solar observatory in more glorious days. “Einstein was here,” a tiny note declares, and it’s true.

Viewed through the 150-foot solar tower telescope, the sun sets behind hills west of Mount Wilson. (Joel Achenbach/The Washington Post)

The telescope still works fine. The sun hits a mirror and the beam of light travels down the shaft to the observing table.

The sun, you might think, is a fairly vanilla object in the sky. It’s the very definition of predictable: rises in the east, sets in the west, etc. The Aug. 21 eclipse will happen precisely on schedule and in the right places. If for some reason the moon does not block out the sun that Monday, we have a really serious problem on our hands.

But the sun is not actually so predictable. The 11-year solar cycle can be boom or bust. And if you’re Padilla, you see a slightly different sun every day.

On this late afternoon, the sun appears initially as a white disk on the observing table. There are no sunspots, but we can see some structure, like granules, on the face of the sun.

As the sun descends, the white disk turns orange.

Padilla does a little demonstration. He takes a drawing of the largest sunspot ever recorded and puts it on the image of the sun. It’s a massive splotch — a truly spectacular solar storm. Then he puts a big marble on the sun’s image. That’s Jupiter. Then he places on the orange disk a ball bearing, not much bigger than what you’d fire from a BB gun.

Now the orange sun is turning into a red sun. The leading edge (“limb”) is dark red, while the trailing edge is blue.

Now we see the shapes of jet airplanes zooming across the image — the sun is looming just above the horizon.

The sun becomes squashed, a misshapen piece of overripe fruit. The image fights its way through the Earth’s atmosphere. The sun hits a hill on the horizon, and we see the outline of trees, and what’s left of the sun is blood red — and then it’s gone, eclipsed by the Earth.

It’ll be back.