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2021 News

Clyde_W._Tombaugh
02/172021

Who Was Clyde Tombaugh?

2021 News, Blog

Photo: Clyde Tombaugh stands with one of his homemade telescopes.

The eldest of six children, Clyde Tombaugh was born on a farm near Streator, Illinois. He began helping his father around the farm at an early age, planting corn, threshing oats and wheat, and various other labor-intensive tasks. He loved reading in his spare time, particularly on the subjects of geography and history. Exploring the world, both in the past and the present, helped make small-town farm life feel a little less small. When Clyde reached his teenage years, however, the world wasn’t enough—the thought of what lay beyond it captured his imagination, and astronomy took over as his favorite interest. Clyde was lent a three-inch telescope and an astronomy book by his Uncle Lee. Clyde would later say it was this book that introduced him the astronomers who would become his heroes: Galileo Galilei, William Herschel, and Percival Lowell.

In 1920, Clyde’s father and uncle purchased a 2¼ -inch telescope from Sears-Roebuck, which Clyde would use to view the cosmos as often as he could. Two years later, the Tombaugh family relocated to Burdette, Kansas, in search of better farming conditions. There, Clyde was overjoyed to discover that the dark skies provided ideal viewing conditions for his telescope.

Clyde became adept at building his own facilities to suit his various interests around the farm, including a football field and tennis court in the family’s pasture, and of course, his own telescopes. The first telescope he built was an 8-inch reflector, constructed with pine board tubes and repurposed farm machinery. Without a temperature-constant environment to test the telescope in, the final product fell short of Clyde’s expectations. To improve his mirror-making capabilities, he used a pick and shovel to dig an underground testing room that doubled as a storage cellar and tornado shelter. After he cemented the walls and ceiling, it became the perfect place to grind telescope mirrors into the right figure.

Clyde Tombaugh, standing at the entrance to the Pluto Discovery Dome.

In February of 1927, he built a 7-inch reflector that he sold to his uncle. He used the money to begin building a 9-inch telescope, which he finished early in 1928. That same year, the Tombaugh family’s crops were destroyed by a hailstorm, and Clyde realized that the farm life wasn’t for him. He was offered a job by a Wichita telescope maker, but before he could accept it, an even better offer fell into his lap. Clyde had been reading some of his older issues of Popular Astronomy Magazine when he saw an observation report on Mars written by staff members from Lowell Observatory. Inspired, he sent some of the drawings he’d created while observing the planets to V.M. Slipher, then Lowell Observatory’s director. After exchanging several letters with Slipher, Clyde received one that would change his life forever. In it, Slipher offered him a position at the observatory on a trial basis, stating that if he could prove his worth to the observatory, he would be offered a more permanent position there.

As we now know, Clyde would go on to discover Pluto, the fabled “Planet X” that Percival Lowell had spent much of his life searching for, within a mere few months of rekindling the search. He then earned bachelor’s and master’s degrees in astronomy from the University of Kansas, fulfilling his lifelong dream of attending college. Clyde would study astronomy for the rest of his life, even after leaving Lowell Observatory in 1945. He taught astronomy at New Mexico State University from 1955 until his retirement in 1973. During World War II, he contributed his experience to the effort by teaching naval personnel navigation at Northern Arizona University and working at White Sands Missile Range. He was inducted into the International Space Hall of Fame in 1980. He died on January 17, 1997, in Las Cruces, New Mexico, at age 90. A small portion of his ashes was placed aboard the New Horizons spacecraft, which flew by Pluto in 2015.

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pluto discovery dome
02/102021

Secrets of Lowell: The Pluto Discovery Dome

2021 News, Blog
Photo: The Pluto Discovery Dome | Sarah Gilbert

Construction on the building known today as the Pluto Discovery Dome was completed in September of 1928, 11 years and 10 months after the death of observatory founder and Planet X seeker Percival Lowell. Though Percival himself would not live to see his Planet X found, this unassuming, two-story telescope dome made of local basalt rock is where the decades-long quest would finally come to an end.

A New Beginning

The fevered search for Planet X was placed on hold for nearly a decade after Percival’s passing in November of 1916, due large in part to a tense legal battle between the observatory and his widow, Constance Lowell, concerning the contents of his will.  This, coupled with the onset of World War 1, brought the observatory to the brink of financial ruin. By 1927, however, the role of sole trustee had been passed onto Roger Lowell Putnam, Percival’s nephew. Determined to bring the observatory back to prominence after a period of financial hardship and low morale, Roger resurrected his uncle’s tireless search for the 9th planet in our solar system. To accomplish this, he enlisted the help of then-director V.M. Slipher. While Slipher planned out the construction of a telescope dome, Roger went about searching for a telescope to inhabit it.

Building a Piece of History

For the location of the telescope dome, Slipher chose a hill located 100 yards west of the observatory’s administration building (now known as the Slipher Building), on land leased from the U.S. Forest Service. This land, as well as the acres behind it, would later become observatory property. Construction on the dome began in early 1928, lead by observatory instrument maker Stanley Sykes. Stanley used a design very similar to the one that his brother Godfrey had used to construct the Clark Telescope Dome decades earlier, employing the same inverted bucket shape for the dome’s roof. The most significant difference in the new design was the addition of a second story, where the telescope itself would be housed and operated. The walls were constructed with cement and Malpais rock* collected from the observatory grounds.

An original sketch of the 13″ Lawrence Lowell Telescope.

Meanwhile, Roger searched for a telescope manufacturer to make use of three partially figured, 13 inch-diameter glass discs acquired from the estate of recently-deceased optician Joel Metcalf, who had been working on the discs at the time of his death. After looking into several options, Roger chose Robert Lundin of Alvin Clark & Sons, whose father had assisted in the construction of the Clark, for the task of assembling a 40-inch reflector to be used in the renewed search for Planet X. The telescope would be an astrograph, meaning that it would be designed solely for the purpose of taking photos of celestial objects. The scope was officially named the Lawrence Lowell Telescope, after Percival’s brother, Abbott Lawrence Lowell.

*A type of basalt found in the Southwestern U.S., Mexico, Spain, and other Spanish-speaking regions of the world. Many of the buildings on our Mars Hill campus and around the town of Flagstaff are constructed with it!

Not in Kansas Anymore

While construction on the telescope and its dome progressed, Slipher received a letter from Clyde Tombaugh, a 23-year-old farm boy from Kansas asking for a professional opinion on the sketches he had made while observing planets through his homemade telescope. Impressed, Slipher exchanged several letters with Tombaugh before offering him a job at the observatory on a trial basis. Slipher was somewhat vague about what Tombaugh’s responsibilities would include, alluding to photography and janitorial work, but stated that he might be offered a more permanent position at the observatory if he could prove his usefulness. As history would show, Tombaugh would go on to prove his worth and then some. He accepted Slipher’s offer and arrived in Flagstaff on January 15, 1929, two weeks after receiving the letter.

Clyde Tombaugh at the guide scope for the 13″ astrograph.

The astrograph and its dome were completed the following month of the same year, and the first exposure was taken on February 16. It was in this dome that Clyde would spend many cold, tedious nights alone, guiding the telescope in search of the elusive Planet X. On one of these such nights, Clyde found himself suddenly feeling very warm and sleepy in the otherwise freezing telescope dome. Had he not recognized this as a sign of hypothermia setting in, he might have frozen to death. On another night, he was trapped inside the dome for several hours while a hungry mountain lion prowled outside. However, these hardships would pay off in a big way on February 18, 1930—exactly 1 year and 34 days following the date that Tombaugh first began his employment at Lowell. He discovered Planet X, which he would later name Pluto, while comparing two exposures he had taken with the astrograph.

Today, the Pluto Discovery Dome stands as a monument to an unforgettable moment in astronomy history. Though the Lawrence Lowell Telescope is no longer used for observation, it was refurbished in 2017 along with the dome to ensure that its legacy can be preserved for generations to come.

 

The Pluto Telescope before it was refurbished in 2017.The Pluto Telescope before it was refurbished in 2017.
The Pluto Telescope after being refurbished.The Pluto Telescope after being refurbished.

New Additions

If you look closely at the telescope, you’ll notice a red boxing glove attached to its metal arm. Ralph Nye, who maintained the Lowell telescopes in the 1990’s, was working on the telescope when he hit his head on the end of the arm. This made him see the wrong kind of stars, so he added the glove as a cushion to prevent it from happening again.

Hidden in a cabinet beneath the motor that drives dome movement is a time capsule. It contains Pluto memorabilia including scientific publications, a hat Clyde Tombaugh wore while observing, and a pencil used by scientists during the 2015 New Horizons Mission. Created in collaboration with New Horizons Principal Investigator Alan Stern, the capsule is to remain sealed until an orbiter is sent to explore the surface of Pluto.

Check out Secrets of Lowell on Tiktok!
@lowellobservatoryWhat’s in that time capsule? And how did that boxing glove get up there? 🤔 The observatory is full of mysteries, but our blog may have some answers.♬ Moonlight Serenade – Glenn Miller

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Pluto91posterDates_web
02/022021

Lowell Observatory Presents 2nd Annual I Heart Pluto Festival

2021 News, Press Release #2021

PRESS RELEASE
FOR IMMEDIATE RELEASE

January 27, 2021

***Contact details appear below***

***Text and images: https://lowell.edu/lowell-observatory-presents-2nd-annual-i-heart-pluto-festival/

***Event website: https://iheartpluto.org/ 

LOWELL OBSERVATORY PRESENTS 2ND ANNUAL I HEART PLUTO FESTIVAL

Flagstaff, AZ. – Lowell Observatory is pleased to present a celebration 91 years in the making: the 2nd Annual I Heart Pluto Festival. Retired NASA astronauts Nicole Stott and Ron Garan and New Horizons scientists Dr. Alan Stern and Dr. Will Grundy headline the event. This free, all-virtual celebration runs from February 13-18 and features a variety of talks, tours, an art show, and a ham radio event. The festival falls on the anniversary of Clyde Tombaugh’s February 18, 1930 discovery of Pluto at Lowell Observatory.

Stott twice flew to the International Space Station (ISS) and also worked aboard the Aquarius undersea habitat. Garan is a retired test pilot and fighter pilot who also twice flew to the ISS and lived on the Aquarius. Both are accomplished artists, and on February 15 they will take part in an open discussion about how they combine the awe and wonder of their experiences to inspire people around the world.

Stern, who led the groundbreaking mission to Pluto that revealed the true nature of this tiny world, kicks off the celebration on February 13 with the presentation “Why Pluto is a Planet, the Embarrassment of the IAU, and Why They Had it Coming”. Grundy is a planetary scientist at Lowell Observatory and will speak on February 16 about our current understanding of Pluto and its system of moons.

Clyde Tombaugh discovered Pluto on February 18, 1930, and since then scientists, artists, and the public have been enamored with this tiny world. Lowell Observatory created the I Heart Pluto Festival in 2020 to celebrate this scientific and cultural heritage. The event will be held around the discovery day anniversary each year, culminating in the 2030 centennial of Tombaugh’s monumental find.

The 2021 schedule is below. For complete I Heart Pluto Festival program details, including how to join the events, see https://iheartpluto.org/

February 13

*6-7 pm MST, “Why Pluto is a Planet, The Embarrassment of the IAU, and Why They Had It Coming”. Presentation by New Horizons Principal Investigator Dr. Alan Stern.

February 14

*6-7 pm MST, “Who was Clyde Tombaugh?” Discussion with Clyde Tombaugh’s son Al, Astronomy Editor-in-Chief Dave Eicher, and astronomy historian Bill Sheehan; moderated by Lowell Observatory Historian Kevin Schindler.

February 15

*5-6 pm MST, “Inspiration of the Cosmos”. Discussion with astronauts Nicole Stott and Ron Garan; moderated by Lowell Observatory Sole Trustee W. Lowell Putnam.

*6-7 pm MST, “Uncovering Pluto”. Behind-the-scenes Pluto tour of Lowell Observatory with Lowell Observatory educators.

February 16

*6-7 pm MST, “Pluto After New Horizons”. Presentation by Lowell Observatory Planetary Scientist Dr. Will Grundy.

February 17

*6-7 pm MST, “When the Moon Hits Your Eye”. Tour of the U.S. Naval Observatory Flagstaff Station with facility scientists; special welcome by Charon discoverer Jim Christy and his wife (and Charon namesake) Charlene.

*7-8 pm MST, “Imagining Pluto: The Artist’s Journey to Envision Pluto Through the Ages”. Discussion with International Association of Astronomical Artists members Dr. Dan Durda, Marilynn Flynn, and Ron Miller; moderated by IAAA member Jon Raimer.

February 18

*5:30-6 pm MST, “Family Night at Pluto”. Family activities with Lowell Observatory Educator Victoria Girgis.

*6-7 pm MST, “Following in Clyde’s Footsteps: Pluto Discovery Day Tour”. Flagstaff tour with Lowell Observatory Historian Kevin Schindler.

*7-8 pm MST, “We Heart Pluto”. Discussion with Clyde Tombaugh’s son Al, Astronomy Editor-in-Chief Dave Eicher, New Horizons Principal Investigator Dr. Alan Stern, former Flagstaff Mayor Coral Evans; moderated by Lowell Observatory Director Dr. Jeff Hall.

Related Events

February 13-18

*“I Heart Pluto Art Show”, with members of the International Association of Astronomical Artists.

February 13-21

*“Hamming it Up”, with members of the Northern Arizona DX Association.

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Media Contact
Kevin Schindler, Lowell Observatory
(928) 607-1387
kevin@lowell.edu

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About Lowell Observatory

Lowell Observatory is a private, nonprofit 501(c)(3) research institution, founded in 1894 by Percival Lowell atop Mars Hill in Flagstaff, Arizona. The observatory has been the site of many important discoveries, including the first detection of large recessional velocities (redshift) of galaxies by Vesto Slipher in 1912-1914 and Clyde Tombaugh’s discovery of Pluto in 1930. Today, the observatory’s 17 astronomers use ground-based telescopes around the world, telescopes in space, and NASA planetary spacecraft to conduct research in diverse areas of astronomy and planetary science. Lowell Observatory currently operates multiple research instruments at its Anderson Mesa station, east of Flagstaff, and the 4.3-meter Lowell Discovery Telescope near Happy Jack, Arizona. The observatory also welcomes more than 100,000 guests per year to its Mars Hill campus in Flagstaff, Arizona, for a variety of educational experiences, including historical tours, science presentations, and telescope viewing.

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The Pluto Telescope after being refurbished.
02/022021

The Discovery of Pluto

2021 News, Blog, News #2021
Photo: The Pluto Discovery Telescope

By Kevin Schindler

Percival Lowell postulated the existence of a planet beyond Neptune and began to search for it in 1905.

He spent his remaining 11 years in a mathematical and observational search for the elusive “trans-Neptunian” planet. Upon Lowell’s death in 1916, the search was suspended while the Observatory went through protracted legal wrangling about Lowell’s estate. In 1927, once the estate was finally settled, Percival’s brother — Harvard University President A. Lawrence Lowell — provided the funds needed to construct the telescope and dome you can still see every day here on guided tours.

The Pluto Discovery Plates, courtesy Lowell Observatory Archives

The glass plates Tombaugh painstakingly compared in order to locate Pluto. | Lowell Observatory Archives

The new telescope was completed in 1929, and the Observatory hired a farm boy from Kansas named Clyde Tombaugh, who had impressed director V. M. Slipher with some unsolicited sketches, to help renew the search.

The process was laborious: Tombaugh would photograph the same part of sky several days apart and use a Zeiss Blink Comparator to detect the motion of a nearby planet against the more distant “fixed” stars. Once Tombaugh got going toward the end of 1929, the discovery came remarkably fast: on February 18, 1930, he detected the distant planet on plates taken on the 23rd and 29th of January.

The discovery was announced March 13, 1930. On the evening of March 12, director V.M. Slipher sent a telegram to the Harvard College Observatory. The telegram’s message was used to create Harvard College Observatory Announcement Card 108, which officially announced the new planet’s discovery and was released on the 13th. Slipher wrote a more detailed account of the discovery and printed it as a Lowell Observatory Observation Circular, also releasing it on the 13th. Astronomer Carl Lampland was busy as well on this day. On behalf of the Observatory, he presented the Lowell Prize to the top mathematics student at Arizona State Teacher’s College at Flagstaff (today known as Northern Arizona University). The ceremony was in front of a 500-person audience in Ashurst Hall. As part of his speech, Lampland made the first public announcement of the new planet’s discovery. Unfortunately, few, if any, of the audience members heard this important message, since the soft-spoken Lampland could not be heard in the echo-filled, uncarpeted room. The announcement date was significant, for it had been March 13, 1781 that William Herschel discovered Uranus. Also, March 13, 1930 would have been Percival Lowell’s 75th birthday, a fitting tribute to the man whose inspiration led to the discovery of this new planet by Clyde Tombaugh.

Check Out #TeamPluto!

90 years ago, Pluto was discovered by scientists at Lowell Observatory. In 2006, Pluto was reclassified as a dwarf planet. How did this happen? This Discovery documentary follows YouTube star and TV host Nick Uhas and a team of esteemed scientists on the quest to understand the fierce fascination with Pluto’s planetary standing. Watch below:

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Screen Shot 2021-02-01 at 12.54.25 PM
02/012021

This Week in Astronomy History | Feb. 1-7

2021 News, Blog, News #2021
Photo: Clyde Tombaugh studies photographic plates through the Blink Comparator | Lowell Observatory Archives

By Madison Mooney

Feb. 2, 1964: Ranger 6 crash-lands on the Moon

The Ranger 6 Robotic Spacecraft | NASA Headquarters – GReatest Images of NASA (NASA-HQ-GRIN) – Great Images in NASA Description

On February 2, 1964, the Ranger 6 probe was deliberately crash-landed on the surface of the Moon to obtain up-close, high-resolution photos of the lunar surface during the final minutes before impact. The probe made impact in the Sea of Tranquility, a lunar mare1 located in the Moon’s Tranquillitatis Basin. The probe carried 6 television cameras, each containing their own power supply and transmitter to ensure the highest probability of success. However, due to a failure in the probe’s camera system, no images could be returned to Earth.


1 A lunar mare (plural “maria”) is a large, dark, basaltic plain on Earth’s Moon, formed by volcanic activity. They were called maria (Latin for “seas”) by early astronomers who mistook them for bodies of water on the lunar surface.

Feb. 4, 1906: Clyde Tombaugh is born

Astronomer Clyde Tombaugh was born in Streator, Illinois on February 4, 1906. He is best known for his groundbreaking discovery of dwarf planet Pluto, then considered to be the 9th planet in our solar system, at Lowell Observatory in February of 1930. At the time of his discovery, Tombaugh was just 24 years old. He is also credited with the discovery of several asteroids, many of which were found as a byproduct of his search for Pluto and other celestial objects.

Tombaugh stands with one of his homemade telescopes | Unknown (Public Domain)

Tombaugh built his own telescopes from scratch while living on a farm with his parents in Burdett, Kansas. He was offered at job at Lowell Observatory in 1929 after sending sketches of Mars and Jupiter based on the observations he had made with his homemade telescopes. After discovering Pluto, he went on to earn a bachelor’s and master’s degree in astronomy at the University of Kansas, fulfilling a dream that had once been dashed by a storm that destroyed his family’s crops.

Tombaugh retired in 1973 after a long, fruitful career that included working at White Sands Missile Range, teaching personnel navigation at Northern Arizona University, and teaching astronomy at New Mexico State University. He died in Las Cruces, New Mexico on January 17, 1997.

Tombaugh received many honors and awards both before and after his death, including induction into the International Space Hall of Fame and the naming of the Tombaugh Regio, a heart-shaped surface feature of Pluto.

Feb. 5, 1971: Mariner 10 makes its closest approach to Venus and Apollo 14 lands on the Moon

A particularly eventful day in astronomy history, February 5, 1971 saw the Mariner 10 space probe make its closest approach to planet Venus and the 8th manned mission in the Apollo program, Apollo 14, complete a successful landing on the surface of the Moon.

Mariner 10’s approach to Venus

An artist’s rendering of the Mariner 10 probe in space | NASA

Mariner 10 was a robotic space probe launched on November 3, 1973, with a mission to complete flybys of Mercury and Venus and gather data on their environments, atmospheres, surfaces, and characteristics. It made its closest approach to Venus on February 5, 1971. After making its closest approach to Mercury on March 29, 1974, Mariner 10 became the first probe to successfully perform flybys of multiple planets, as well as the first to complete a dual-planet gravity assist mission.1

Apollo 14 landing

Alan Shepard standing with the American flag on the Moon | Edgar Mitchell, NASA

Apollo 14 astronauts Alan Shepherd, Edgar Mitchell, and Stuart Roosa began their journey to the Moon on January 31, 1971, touching down on the lunar surface 5 days later.

During their two surface walks, Shepherd and Mitchell collected Moon rocks and performed several scientific experiments. Perhaps most notably, Shepherd hit two golfballs he’d brought with him with a makeshift golf club. Meanwhile, Roosa remained in orbit to conduct experiments and photograph the lunar surface. At the request of the National Forest Service, he brought hundreds of tree seeds with him on the mission to be planted upon his return. The three astronauts touched down safely in the Pacific Ocean on February 9.


1 In the case of the Mariner 10 mission, the probe used Venus’s gravitational pull to “slingshot” itself toward Mercury.

Feb 6. 1994: Clementine enters lunar orbit

Artist’s rendering of Clementine fully deployed in space | Public Domain

Clementine (originally the Deep Space Program Science Experiment) was a lunar orbiter and asteroid probe launched by NASA and the Ballistic Missile Defense Organization on January 25, 1994. Its mission was to make detailed observations of the Moon and nearby asteroid 1620 Geographos, while also testing the effects of long-term exposure to space on its sensor and components. It failed to reach the asteroid because of a system malfunction, but was able to collect ultraviolet and infrared images of the lunar surface and measure various aspects of the Moon’s gravity and atmospheric pressure. Using data gathered by Clementine, scientists were able to create a detailed profile of conditions on the Moon’s surface.

The probe’s name was derived from the popular American folk ballad “Oh My Darling, Clementine,” as it would be “lost and gone forever” after its mission was over.

 

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Flagstaff, AZ — February 12 - 16, 2026

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