Belgian Transit of Venus Observation Site TX12188

The year 1639 marked the first recorded observation of Venus crossing the Sun. Sir Edmund Halley (1656-1742) later predicted that using data from such crossings, known as transits, scientists could precisely quantify the astronomical unit of distance and measure the size of the solar system. The transits of Venus predictably come in pairs, eight years apart, approximately every 120 years. Scientists from around the world traveled to observation sites during the next events, in 1761 and 1769, but timing of the transits was difficult due to the "black drop effect," in which two objects against a bright background appear to blend. For more than a century, astronomers prepared for the next opportunity to record Venus' transit. Jean-Charles Houzeau (1820-1888) was a Belgian astronomer with an eclectic history. From 1859 to 1861, he worked as a surveyor in Uvalde, Texas. An abolitionist, he left Texas at the start of the Civil War. In the late 1870s, he returned to Belgium, where he became director of the Royal Observatory and planned the Belgian teams that would go to the western hemisphere to observe the December 1882 transit of Venus. He chose one site in Chile and one (22 feet east) in San Antonio. Good observations required clear skies, and San Antonio offered the chance of favorable weather, as well as good logistics for communication and transportation. A U.S. Naval Observatory team observed from a site on the grounds of nearby Fort Sam Houston. Using a heliometer, a device he had developed for the observation, Houzeau obtained 124 photographic plates of Venus silhouetted against the Sun. Because of clearer conditions, the team in Chile obtained 606. The Belgian findings equaled those of larger nations, and Houzeau's decision to bring an international team to San Antonio provided the city recognition as part of astronomical history.

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Discoverer of Pluto KS109
Burdett is the boyhood home of Dr. Clyde Tombaugh, discoverer of the planet Pluto. Born in Illinois in 1906, he grew up on a farm northwest of here and was graduated from Burdett High School in 1925. During his youth, Tombaugh explored the heavens with homemade telescopes. Later he was hired by Lowell Observatory, Flagstaff, Arizona, and discovered Pluto, the outermost planet in our solar system in 1930. During his planet search, Tombaugh photographed 65 percent of the sky and spent 7,000 hours examining about 90 million star images. Besides Pluto, his discoveries included six star clusters, one cloud of galaxies, one comet and about 775 asteroids. Few astronomers have seen so much of the universe in such minute detail. Dr. Tombaugh earned degrees from the University of Kansas and Northern Arizona University. He concluded his career as an astronomy professor at New Mexico State University.

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Montgomery County MO13
MONTGOMERY COUNTY

One of the first settled areas north of the Missouri (River), Montgomery County was an early gateway to the Boone's Lick Country. Organized, 1818, and named for Gen. Richard Montgomery, it was a vast area and first two county seats, Pinckney and Lewiston, lay in what is now Warren County. Danville, the third county seat, was succeeded, 1924, by Montgomery City, founded 1857, when the North Missouri R.R.(Wabash)reached there.

Historic Danville, founded 1833-34, was a prominent town on the Boone's Lick Trail and popular stops were See-Nunnelly and Fulkerson taverns.

J.H. Robinson's Female Academy, 1857-65, was a noted early school. The Academy Chapel, built in 1859, is now a Methodist Church. In the Civil War, Danville was looted and burned, Oct.14, 1864, by Bill Anderson's guerrillas. This severe blow and not being on the railroad resulted finally in the loss of the county seat, after a long struggle, to Montgomery City.

The county was surveyed by Nathan and Daniel Morgan Boone, sons of Daniel Boone. Daniel M. lived near Mineola for a time and another son, Jesse, settled near Danville.

In a grain and livestock farming region, Montgomery County lies in territory ceded by Sac and Fox Indians in 1804, the first Indian land cession in Missouri. Southern pioneers who followed Daniel Boone to MO. made the county's first settlement on Loutre Island at the mouth of Loutre River on the Missouri, 1807. A number of Germans, the followers of Gottfried Duden, came in the 1830's.

The Loutre (Otter) River, long known to French trappers, was first named Fouchure (Forking) by explorer De Bourgmond, 1714. The Lewis and Clark Expedition camped at the river's mouth, 1804. In the War of 1812, rangers were stationed at Fort Clemson on Loutre Island. Indians killed Captain James Callaway near Danville, 1815.

Mineola, to the south, was laid out as a spa in 1879, near a mineral spring where Isaac Van Bibber had settled, 1815, and built a tavern on the Boone's Lick Trail. Graham Cave, at Mineola, has been utilized by man since prehistoric times. Astronomer Thomas J.J. See was born in Montgomery City and Supreme Court Justice Walker J. Lovelace made his home in Danville.

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McDonald Observatory of the University of Texas TX10480

Original unit in complex forming one of the great observatory centers of the world. Built in the 1930s under terms of legacy from William Johnson McDonald (1844-1926), a Paris (Texas) banker interested in the stars. A well-educated man, McDonald lived frugally. As a hobby, he read science books and viewed planets through a small telescope. His will granted to the University of Texas $800,000: "to build an observatory and promote the study of astronomy."

This site was selected because of its high ratio of clear nights, its 6,800-foot altitude, and its quite low latitude that permits observation of southern skies.

The observatory was operated for its first 25 years mainly by astronomers from the University of Chicago, more recently primarily from the University of Texas. Until 1948, its 82-inch telescope was second largest in the world. Its fine work and site have resulted in the addition of other telescopes including a 107-inch instrument sponsored jointly by the National Aeronautics and Space Administration, the National Science Foundation, and the University of Texas.

Discoveries made here have included interstellar polarization and the satellites of several planets.

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Benjamin Banneker Institute PA120
Founded here in 1854 and dedicated to the literary betterment of African Americans, this school was named for a Black astronomer and mathematician who published an almanac and helped survey Washington, D.C.

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Rittenhouse Farm PA1580
David Rittenhouse, colonial scientist, astronomer, and instrument maker, lived on a nearby farm, where he built a telescope, said to be first made in America, and observed the transit of Venus in 1769.

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Andrew Ellicott PA63
Surveyor, mathematician, astronomer. Secretary, Pennsylvania Land Office, 1801-08. In 1803, while living here, he taught Meriwether Lewis surveying and navigation skills. Helped survey & draw boundaries of New York, Pennsylvania, Washington, D.C., & elsewhere.

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Brashear House PA182
John A. Brashear, astronomer, educator, was born here 1840. His grandfather kept the Brashear House, a leading tavern. In 1825 Lafayette spoke from its doorway to the people of Brownsville.

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First Aluminum Observatory Dome PA557
On the hill just west of here, the first known astronomical observatory with an aluminum dome was erected in 1930. Designed & built by Pittsburgh amateur astronomers led by Leo J. Scanlon, the Valley View Observatory stood beside his Van Buren St. home. In the ensuing years, many of the world's observatories were built with such domes. Scanlon's shiny metal dome became a model for the popular image of a modern observatory.

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Von Schmidt State Boundary Monument NV188
This marker commemorates the iron column erected in 1873 at the southernmost tip of the boundary survey line run by Allexey W. Von Schmidt, U.S. astronomer and surveyor. The line dividing Nevada and California was based on preliminary geodetic work by Lieutenant Joseph Christmas Ives. Ives determined the Colorado River end of the proposed oblique California-Nevada boundary. Von Schmidt calculated and ran the first complete survey of the boundary. His solar observations erred slightly--the actual line now being 3/4 mile to the north.

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