tours of yerkes observatory

• Exploring the Night Sky Tour Dates for Summer 2024

April 29, 2024

Exploring the Night Sky with the Great Refractor tour tickets for Summer 2024 are available now on our ticketing website ! We’re pleased to announce new youth pricing for this experience starting in June. For youth ages 13-18, prices are now $85. Adult tickets are $140.

With only 12 tickets available for each tour, this exclusive evening illuminates the inner-workings of Yerkes Observatory after dark. Curated by our Telescope Team, each tour features a viewing of the cosmos with the largest refracting telescope in the world if skies are clear. If skies are not clear, we’ll delve into Yerkes vaults with 180,000 glass astronomical images, explore the evolution of astrophotography through over a century of equipment, and visit darkrooms in our subterranean chambers.

Regardless of atmospheric conditions, this is a two-hour immersion inside the observatory that changed the way we see the Universe. This is a night event, thus it’s an experience best enjoyed by ages 13 and up. Because of the historic construction of the building and domes, there are several flights of stairs (standard, steep, and tight spirals) that will be climbed and descended during both the clear and cloudy night programs. As such, this experience is not wheelchair accessible.

Exploring the Night Sky tours with the Great Refractor will take place on the following dates:

Frequently Asked Questions

In order to safeguard the condition of our telescopes, we will observe when it is mostly clear (most stars visible), with humidity levels below 85%, wind speeds below 45 mph, there are no active air quality alerts, and the temperature is above freezing (32 degrees F).

We cannot guarantee clear skies on the night you scheduled, but in the event that the weather does not permit observing with our telescopes (or there are technical issues with the historic equipment), we guarantee a special, exclusive experience where you will explore the night sky from a historical perspective on our indoor evening tour.

If there is lightning or severe thunderstorm risk, we will cancel the event as a safety precaution. You will be fully refunded should we have to cancel because of weather.

Our address is 373 W. Geneva Street in Williams Bay, Wisconsin. Turn into our driveway at Geneva St. and Observatory Place by the Yerkes Observatory sign. Our parking lot is on the southeast side of the building. Stay left in the oval driveway and wind around to the lot. Keep veering left keeping the yellow home on your left. Please do not pull in front of the northside doors of the Observatory.

Our ADA spots are in the main parking lot in the southwestern corner of the lot. They adjoin the pathway to the south (lakeside) doors. We also have EV charging stations in our lot.

The observatory was built in 1897 and so the Great Refractor and the 24” telescopes is not easily accessible. There are several flights of stairs (standard, steep, and tight spirals) that will be climbed and descended during both the clear and cloudy nights. If you have concerns or would like to request accommodations, please contact us at [email protected] at least 2 business days prior to your tour. Please note that we are an historic observatory, so while we will do our best to provide accommodations, we cannot guarantee them.

Light refreshments will be provided at the beginning of the tour and you are welcome to bring your own water bottle. There are no alcoholic beverages allowed at observing events.

The telescopes are open to the night air and it can get cold, so please dress accordingly.

To enter the Observatory itself, walk the pathway from the lot to the south entrance. We’ll greet you at the doors about 10-15 minutes before your start time. Please arrive 10-15 minutes early to check in. Bring your email confirmation with you on your phone or printed.

To ensure the quality of the experience for all guests, late arrivals will not be admitted and will not be rescheduled or receive a refund. Space may not be available due to our maximum occupancy per tour. Online reservations are required. Other people with you may not enter the building and browse the exhibits or rooms. Everyone must have a reservation and time slot. Observatory staff members are the only people able to take visitors around the Observatory.

No. An admission ticket purchased in advance shall become invalid upon the expiration of the time or period stated on the ticket. All ticket recipients must be present during purchase. Admission tickets cannot be transferred, refunded or exchanged. If you need to reschedule your night, please email us Monday through Friday during business hours at [email protected]. All sales are final.

The Gift Shop will be open at the end of your tour and is a card only service (no cash or check).

Because our construction and restoration is ongoing, Yerkes Observatory may restrict access to or close any of its property and cancel ticket reservations without advance notice, reason, cause, or explanation at any time.

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America's Most Historic Observatory Is Reborn—And Open for Tours

Yerkes Observatory, home to the largest refracting telescope in the world, was almost lost for good. Saved by its Wisconsin community, its second life is a must-see.

Jacqueline Kehoe of Madison, Wisconsin, works as a freelance journalist, editor and photographer. Her work has appeared in publications like National Geographic, Travel + Leisure, Afar, Lonely Planet, Sierra, Backpacker and Thrillist.

Edwin Hubble and Carl Sagan lived in the same attic. Forty-three years apart, they worked and studied a floor below, in the same rooms where Nancy Grace Roman, NASA's first chief of astronomy, studied the motion of stars; where Gerard Kuiper figured out the other side of Neptune; where William Morgan discovered the shape of the Milky Way.

Like binary stars, these stories orbit around Yerkes Observatory in Williams Bay, Wisconsin, about 6 miles east of Lake Geneva. Widely regarded as the most historic observatory in America—and home to the largest refracting telescope in the world—this forgotten masterpiece was almost demolished. The local community gathered to save it, and today, it's inviting all of us to visit and interact with history, art and space.

A Midwestern—and Global—Icon Reborn

Yerkes Observatory, property of The University of Chicago, was the first astrophysics school in the nation. But by 2005, the 1897 Beaux Arts masterpiece had gotten too expensive to maintain, and the university wanted the property off its hands. There were proposals to turn it into a resort, a spa, a subdivision—and then locals intervened.

"The community raised a fuss," says Walt Chadick, the observatory's director of programs and external affairs. "A lot of people stood up and said, 'Hold on. This is America's most historic, most celebrated observatory. We need to protect this heralded place.'"

The university donated the facility to a community-led nonprofit, Yerkes Future Foundation , in 2020—books, slides, telescopes, trash and all. It was an archaeological site: Rummaging through the attic, YFF staff found relics like Hubble's dissertation and Gerard Kuiper's lunar sphere. In the basement, yellowing dark rooms reeked of hydroquinone and acetic acid, and Reagan's "Star Wars" lasers sat gathering dust.

By 2022, the foundation had raised roughly $14 million for renovation, and the public was invited inside—in small, reserved groups—to wander the halls of Hubble, to gaze upon the Great Refractor, to thumb through books with famous autographs on library cards. "We began with just me," says Chadick, "taking people through construction sites, through those stuck-in-amber places." While certain areas will remain in amber—like the first computers used in 1973—the majority of the facility will be fully restored over the coming years.

"We don't want to be a dusty relic," Chadick explains. "We want to be a forward-thinking modern maker of things."

A New Era for Yerkes

Don't call it a "museum," says Chadick—the observatory's doors are locked, and timed tours can only be reserved online. The classic tour explores the "big dome" with the Great Refractor, the rotunda, and the building's architectural highlights; the "Hidden Spaces" tour ventures into the smaller domes with smaller telescopes, the old darkrooms, and dormitories where the PhD students lived; and the landscape tour explores the grounds (designed by John Charles Olmsted, son of Frederick Law Olmsted) and Yerkes' new status as an internationally accredited arboretum. Five miles of newly blazed woodland trails maze throughout the property for extra exploration.

Special events, though, are where the observatory—which is still functioning, Chadick adds—shines like a supernova. Star parties pepper the calendar, telescope viewing nights bring the public to the Great Refractor, and artistic collaborations turn the facility into an innovations incubator. Thirty musicians from the Blackbird Creative Lab wrote and performed a symphony onsite, composed from interpreted astronomical images; U.S. Poet Laureate Tracy K. Smith was featured in the Summer Speaker Series; and Ashley Zelinskie, the official sculptor for the James Webb Space Telescope, built a black hole space-time continuum sculpture in the side yard.

"I don't know anywhere on Earth where astronomers collaborate this closely with artists," says Chadick. "We want artists to be illuminated, astronomers to have the chance to work with and teach diverse thinkers and creators, and people to leave filled with joy."

Book tours in advance at yerkesobservatory.org .

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The Midwest has another astronomic first: Adler Planetarium , the first planetarium in the country. See Chicago's night sky as it appeared more than 100 years ago via the Atwood Sphere, catch sky shows in one of two dome theaters, and gaze through the city's largest publicly accessible telescope at the Doane Observatory.

Cosmosphere, Hutchinson, Kansas

Partspace museum, part STEM education center, Cosmosphere —roughly an hour northwest of Wichita —brings its visitors a chance to live out their astronaut dreams. Try on a space suit, hop in a cockpit, scope out Russian space artifacts and catch a show in the Justice Planetarium.

Voyageurs National Park, Minnesota

The only dark sky–designated national park in the Midwest, Voyageurs National Park —a forested, lake-filled expanse just south of the Canadian border—offers designated night-sky programs as well as opportunities, night after night, to stargaze, count flying meteors, and witness the spectacular northern lights .

Inside the 124-year-old observatory that birthed modern astrophysics

Home to the world’s largest refracting telescope, the Yerkes Observatory in Wisconsin was so influential that Albert Einstein insisted on visiting. Now you can too.

Inside the dome of Yerkes Observatory, tucked along the shore of Wisconsin’s Geneva Lake, in the town of Williams Bay, it is emphatically 1897. The still-rotating metal half sphere is dominated by an enormous, lovingly polished refracting telescope—a 60-foot-long, six-ton contraption with two 40-inch lenses at one end and an eyepiece at the other. The thing is almost ridiculously fanciful.

If an astronomer or a visitor wants to look through that eyepiece, an operator flips an ancient switch and the dome’s entire circular floor—at 75 feet in diameter, one of the world’s largest elevators—rises 23 feet to give the person access. Then, in a maneuver familiar to any backyard stargazer, the viewer takes hold of the massive telescope with two hands and physically shifts the impeccably balanced device toward the desired point of light.

Ironically, the cost of maintaining all this low-tech equipment is dauntingly high. Today, as tour groups shuffle through Yerkes, it’s easy to forget that the observatory nearly met with a wrecking ball after the University of Chicago closed it in 2018.

They call Yerkes the birthplace of modern astrophysics, but when I visited the facility about two years ago, it looked more like a place teetering on extinction. The monumental telescope was draped in thick, clouded plastic sheeting that movie gangsters tend to use to wrap the bodies of their victims. It was a humbling state for a precision device that was once a magnet for the elite of astrophysicists and theoretical astronomers—Albert Einstein, Edwin Hubble, Gerard Kuiper, and Carl Sagan among them.

But even as I tried to make out the telescope above, Yerkes was being reborn thanks to a $15 million facelift—inside and out—financed by a nonprofit group that took possession of the building in 2020. For the first time in more than a century, the observatory—including its 50-acre grounds—is open for public tours of its working space-science facility.

Over the past few years, Yerkes staff have been preparing for what they expect to be one of the busiest days the institution has ever seen: North America’s total solar eclipse on April 8, 2024. Williams Bay will see 90.2 percent totality, and Wisconsinites who don’t want to drive hundreds of miles to witness complete darkness could find no more compelling a setting for near totality than here beneath these storied domes.

( The best places to see the 2024 total solar eclipse. )

But the glories of Yerkes are not confined to the heavens: The building itself is a thing of beauty. Festooned with elaborate Victorian-era stone carvings, Romanesque arches, and terra-cotta figures, the landmark observatory was created by George Ellery Hale and Charles Tyson Yerkes—two men with very different agendas.

Hale, an astrophysicist, had the then revolutionary notion to establish a facility that housed both an observatory and an academic institution at which physicists and chemists applied their discoveries to new theories about astrophysics. Financier Yerkes, on the other hand, was one of Chicago’s most hated businessmen. He poured money into the observatory to rehabilitate his image, but it didn’t work—and he ended up moving to New York.

Yerkes’s face, however, is depicted on the observatory’s exterior columns—albeit with a sinister smile and devilish horns. “The artists had fun with that,” notes Dennis Kois, executive director of the Yerkes Future Foundation, which inherited the observatory from the university. “Nobody liked Yerkes.” The telescope’s 500-pound lens—cast in France, ground in Massachusetts—made the instrument the biggest ever version of the handheld, two-lens, direct-view telescope used by Galileo in 1609. Because Yerkes’s was one of the first large telescopes designed for photography, its tube needed to rotate with absolute precision to follow star tracks—a feat accomplished by a team of men who turned the gargantuan device one click at a time.

Even after reflector telescopes, which use mirrors to collect and focus light, became the favored tool for space studies, Yerkes’s staff continued to publish influential papers. Its archives hold thousands of research works—including Hubble’s original 1920 doctoral thesis.

In 2018 the university began winding down its Yerkes presence. Astronomers comparing present-day star positions with where they were a century ago still referenced Yerkes’s 175,000 photographic plates, but the halls, once bustling with scientists, fell silent. When the call went out to support the restoration project, the influx of cash from astronomy and architecture enthusiasts across the United States, including many from the neighboring town of Lake Geneva—for nearly 200 years a playground of the Chicago rich—was overwhelming.

“People have always wanted to visit here,” Kois says. That almost mystical appeal persists today, whether visitors are star buffs or not. “There’s something about looking directly into a beam of light that has traveled millions of light-years just to end up at the back of your eyeball.”

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Yerkes Observatory

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Yerkes Observatory - All You Need to Know BEFORE You Go (2024)

• Thu - Mon 9:30 AM - 5:30 PM
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Yerkes Observatory Tours

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“ Walt was phenomenal; hilarious, knowledgeable, charismatic, one of the best tour guides I've ever had. ” in 3 reviews

“ Beautiful restoration of a working refractory telescope mounted on a huge elevated platform. ” in 3 reviews

“ The building has been beautifully restored, and the individuals giving the tours are extremely knowledgeable and passionate . ” in 2 reviews

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373 W Geneva St

Williams Bay, WI 53191

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Walt was phenomenal; hilarious, knowledgeable, charismatic, one of the best tour guides I've ever had. Building is stunning; the architecture is something to marvel over (all the details!!); the observatory and the history and the science are well worth a trip.

What history! Einstein, Sagan, and Hubble all made significant contributions to the field while working at Yerkes. The building has been beautifully restored, and the individuals giving the tours are extremely knowledgeable and passionate. I'd love to come back for an opportunity to look through the massive telescope - that would be a memorable life experience.

See all photos from Lisa S. for Yerkes Observatory Tours

I found this place to be very awesome. I think the previous reviewer where they gave bad feedback maybe had higher expectations, plus they went as they were in the earlier stages of renovating. Tour was about 90 mins and it was very detailed on the history of this observation tower. Great view of the big telescope and they used the elevated platform to bring us up closer to it. The pictures I'm posting should say it all, words can't express how great this place is!

Here for a wedding. Absolutely stunning! Amazing preservation work and a amazing staff!

Yerkes Observatory is a shrine to science. Now it is being restored to remind us of how far we have come, the hard work needed to bring us here, and the need to continue creative work and discovery today. You can walk the halls where astronomers and astrophysicists did the physical work to expand our knowledge of how we fit into larger structures of the universe. You can see how and where they laid the groundwork for observations now done on remote mountaintops and from orbit. And you can better understand the individuals and the tools they used from the end of the 19th Century to the middle of the 20th Century. Seeing and feeling the wood, metal, and bricks at the foundation of the observatory makes their work more real than any book or pictures could. My wife and I took the tour hosted by Walt Chadick, who effectively conveyed the historical scope and significance of the work done by decades of scientists at the Yerkes Observatory. He also described the work in progress, and yet to be performed, so that everyone on the tour got a glimpse of the finished restoration despite it being less than half accomplished today. Troy D.'s review called the tour "overpriced" and complained that there wasn't even "an IMAX theater or singing Tesla coils" or science hands-on for kids. Troy D.'s review misses the point. The whole reason for flashy exhibits is that those exhibits are at places other than this, the original source of knowledge; this is the one place in the world where these scientists actually did their observational work. The tour price is reasonable precisely because the place is unique, is integrated into a unique landscape (designed by the legendary Olmsted firm), and cannot be experienced anywhere else. Although astronomy and astrophysics have moved on to more remote platforms, Yerkes Observatory remembers the world-changing work of the past, and will use that example to inspire others to observe the world and create new expressions in other disciplines. I am looking forward to a return visit to see what transpires.

I took a group to Yerkes Observatory and we had an outstanding tour! With the change of ownership and the downtime the facility experienced through the pandemic, I had no idea what to expect, but the team there has knocked it straight out of the park! Awesome! The building is gorgeous, with the restoration being exceptionally well done, and Walt Chadick was an absolutely fantastic guide who got the Yerkes story across brilliantly. I heard nothing but rave reviews from my group! If you haven't been to Yerkes Observatory, or of it's been many years, you need to get there, see the place, and meet the passionate people who are now in charge. Yerkes is a secret that needs to get out! It really is an international treasure, and it's been brought back to life beautifully!

My wife and I booked the tour and were surprised at the cost at first. However, the tour was more then worth the price. There were some unbelievable documents and pieces of American history that one can see. The place is still under reconstruction, and while perhaps we didn't see all the completed exhibits that will exist one day, it felt more almost of a behind the scenes tour. 100% recommend, my wife and I have booked tickets with my folks to go back next week. If you are at all interested in the cosmos - you must go!

40 in (100 cm) refractor at the Yerkes Observatory

Inside the Observatory (currently under renovation)

Overpriced for locals and families. The place isn't a museum and has no planetarium, no installations of any science hands-on for kids. Not even an IMAX theater or singing Tesla coils. Yawn.

Pricing for an hour walk-thru...

Went on the first ever landscape tour. Walt was a tremendous tour guide. The whole thing was beautiful and informative--I never would have guessed this observatory and the surrounding property had such incredible history.

Fascinating 90 minute tour of this facility which has architectural, scientific and historical importance. Beautiful restoration of a working refractory telescope mounted on a huge elevated platform. Walt, our guide, had boundless enthusiasm and deep knowledge of the facility and the important discoveries made here. Definitely worth the price of admission!

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Yerkes Observatory Tours

Yerkes Observatory has been a hub for research and education since it opened in 1897. The Williams Bay facility sits on a 70 acre site adjacent to Geneva Lake and is home to the world's largest refracting telescope. The observatory has been restored and is open for tours begining in the Spring 2022.

During the tours, the guides provide a brief talk on the history of Yerkes, the architecture, astronomical research and the universe. Throughout the years, many notable scientists have worked at Yerkes or with collaborators here, including Albert Einstein and Edwin Hubble. The observatory is open daily from 9am to 5pm with tours being offered throughout the day Thursday through Monday. Check their website for details.

Latitude 42 34.2 Longitude -88 33.4

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Yerkes Observatory

Tours available Thursdays-Mondays from May till October and two to three days a week during the shoulder seasons. Tickets available ONLINE ONLY . Click HERE for more information and to reserve your tour or event. 

Hello, 2024! WE ARE OPEN! Yerkes Observatory, the birthplace of modern astrophysics, is an architectural masterpiece on fifty acres of Olmsted-designed ecological splendor. Since 1897, Yerkes has been the home and school to famous astronomers, Nobel prize winners, and renowned scientists but we're now open for public tours, observing nights, star parties, weddings, exhibits, trail walks, and more. The world-famous Observatory's beautiful location in Williams Bay, Wisconsin is only twelve minutes from downtown Lake Geneva. We are on a new voyage under the stewardship of Yerkes Future Foundation, a nonprofit 501c3. All proceeds go to the restoration, preservation, and programs of this international landmark of astronomy, architecture, and landscape design. Don't miss these behind-the-scenes, out of this world, restoration tours! For further information,  please visit our website.

• Number of Meeting Rooms: 4
• Price Range: $$
• Level of Difficulty: Medium
• Largest Group Capacity: 100 indoor and 300 outdoor

Facility Info

• Reception Capacity 150
• Banquet Capacity 150
• Number of Rooms 5
• Classroom Capacity 130

Yerkes Observatory Presents: Sci-Fi Film Series

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Directors Hidden Spaces Tour of Yerkes Observatory

Yerkes Observatory

The dawn of yerkes observatory, a marvel of its time: the world’s largest refractor, restoring cobb’s masterpiece, the evolution of astronomy at yerkes, treasures of astronomical history, illuminating solar mysteries: the sun reflection room, the future of observation: robotic telescopes, yerkes on screen: the ‘chain reaction’ connection, honoring george elroy hale’s legacy, capturing the cosmos: the kodak medalist legacy, pioneering space with wavefront experiments, archival wonders: pages from the past, cosmic memories: souvenirs of the stars, yerkes observatory: a beacon of resilience and discovery.

2-hour, 30-minute guided tour Yerkes Observatory, 373 W Geneva St, Williams Bay, WI 53191

As the sun climbed into the sky on a warm July afternoon, we found ourselves at the gates of the Yerkes Observatory. It was 10 am, and the day was set to be one filled with cosmic intrigue and a voyage into a time when giants walked the earth. By giants, I mean towering intellects who revolutionized the realm of astronomy.

Upon arrival, we joined the other tour participants, a group of ten, and we were warmly welcomed by Dennis, the director of the observatory. He began to introduce us to the illustrious history of the Yerkes Observatory, whose story begins back in the late 19th century.

From 1895 to 1897, under the supervision of the University of Chicago, construction began on the observatory, backed by the financial prowess of the elusive financier and philanthropist, Charles Yerkes. A figure as controversial as he was influential, Yerkes’ name is interwoven into Chicago’s history. Despite his notoriety, his astronomical contributions stand undisputed. His only caveat? The observatory had to be built within a hundred-mile radius of Chicago.

Until 1913, the Yerkes Observatory was renowned for housing the world’s largest refracting telescope. This 40-inch marvel, crafted by the renowned telescope makers Alvan Clark & Sons, was a marvel of its time. Its unprecedented detail attracted leading minds of the era, including Albert Einstein, and established the observatory as a landmark in astronomical science.

Designed by the illustrious Henry Cobb, the Yerkes Observatory is a testament to architectural brilliance, its grand entrance framed by majestic pillars. Among these, the playful “bee sting” on the John D. Rockefeller busts, a subtle nod to one of the era’s giants, highlighted Cobb’s creative flair.

Despite its splendor, time took its toll, and the observatory fell into disuse. However, in 2020, a determined restoration project resurrected this heritage site, replacing antiquated wiring and diligently restoring Cobb’s masterpiece, reigniting the luminosity of this astronomical sanctuary.

As we ventured further into the heart of the observatory, a rich tapestry of stellar achievements, each telling a unique story of astronomical progress and discovery, began to unfold. The observatory’s triumphs ranged from capturing the lunar images that underpinned the Keiper map to harboring a seminal 1718 book speculating about life beyond Earth, echoing its enduring influence in the field of astronomy.

The journey through the corridors of discovery transitioned to a celebration of technological evolution. The shift from manually drawn sketches to photography, a groundbreaking leap in astronomy, is manifest in the observatory’s extensive archives. The historical repository ranged from photographic slides from the 1920s to rooms of plate records, underscoring the observatory’s ceaseless march towards progress and innovation.

The culmination of this exploration was an upstairs room dedicated to historical artifacts. It housed logbooks of telescopes and a blink comparer—a device that highlighted discrepancies in astronomical images, providing a tangible expression of the observatory’s thirst for knowledge. Among the myriad artifacts, a 40 x 40 full solar eclipse plate from 1902 was a standout, symbolizing the breadth of the observatory’s work and its rich heritage.

Our exploration of the observatory advanced to a special nook hidden in the attic – the sun reflection room. This room, a relic from the early days of solar physics, was ingeniously designed to channel sunlight through a system of mirrors and lenses.

It served as a controlled environment for observing and scrutinizing the sun’s many properties, from the study of enigmatic sunspots to the investigation of solar flares and the solar magnetic field. These studies were crucial to our understanding of space weather, an area of research that can greatly impact satellite communication and terrestrial power grids.

Progressing further, we ascended to a small dome that housed an impressive modern spectacle – a robotic-controlled telescope. This wasn’t any ordinary instrument; it was a 40-inch reflector telescope constructed in 1967 by the reputable Warner & Swasey Company from Cleveland, Ohio.

A trusted manufacturer of precision instruments and telescopes in its prime, the company was a significant contributor to the world’s largest telescopes in the early 20th century.

In these very attic spaces of Yerkes, several scenes from Keanu Reeves’ movie ‘Chain Reaction’ were filmed which adds a fun pop culture connection, serving to further highlight the observatory’s enduring relevance and appeal.

Within the depths of the basement lay a memento of personal significance – George Elroy Hale’s childhood telescope. This pioneering American astronomer’s legacy is indelibly linked to the observatory, a fitting homage to his monumental contributions.

As the clock struck 12:30 pm, we reached the culmination of our tour. We first stopped to marvel at an immense photo enlargement apparatus. This machine, utilized to replicate detailed telescope observations, operated on a specialized medium – the Kodak Medalist photographic paper.

Renowned for its high silver content, this paper offers an exceptional grayscale rendition, enabling astronomers to capture nuanced details of celestial bodies.

Following this, we proceeded to an intriguing room housing a light table. This particular light table was central to a series of wavefront control experiments, also known as the Starlab experiment. The goal of these experiments was twofold. On one hand, they sought to ascertain how wavefronts, the unbroken surfaces of a wave, could be manipulated in real time. On the other, they aimed to understand and further the development of the ‘chaos laser’ theory.

The ‘chaos laser’ under invention was designed to utilize chaotic light patterns to improve image quality, particularly in space applications. The light table and the wavefront control experiments it hosted were critical to this research, offering a testbed for the chaos laser’s effects on wavefronts.

The ultimate ambition was to perform these wavefront control experiments aboard a space shuttle, thus bridging terrestrial research with cosmic exploration. The potential results from these experiments could significantly enrich the field of advanced adaptive optics. This is a technological area that strives to minimize the atmospheric distortion that earthbound telescopes experience, allowing for an increasingly precise view of the cosmos.

In this way, the light table served not only as an intriguing relic of astronomical history, but also as an emblem of our continuous quest for deeper, more nuanced understanding of our universe and the technology we create to explore it.

Our tour’s final chapters unfolded in the observatory’s main library, where history whispered from the shelves. Highlights included a December 1909 edition of Scientific American with Yerkes Observatory on its cover, and the manuscript “Photographic Investigations of Faint Nebulae.” This manuscript, rich with astronomical heritage, had an extraordinary journey, traveling to space with astronauts on Shuttle Mission STS-109, symbolizing the blend of earthly discovery and cosmic exploration.

Adjacent, two archive rooms, styled as living museums, offered a deep dive into the observatory’s past, bringing to life the stories and achievements of its astronomers.

Concluding our visit, the gift shop presented a collection of memorabilia and astrological wonders, allowing us to take a piece of the cosmic journey home. This section of the tour encapsulated the observatory’s legacy as a crucible of astronomical discovery, linking the past with an ever-expanding future.

The Yerkes Observatory, once a giant abandoned by time, now stands proud once again, ready to inspire new generations of astronomers. From its historic origins to its modern resurrection, the observatory truly is a beacon of astronomical advancement, and its tale is one of resilience and the undying pursuit of knowledge.

Cruise Port:  Williams Bay, Wisconsin

Tour Name:  Directors Hidden Spaces Tour

Tour Operator:  Yerkes Observatory

© OceansAfoot

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