"The Red Skies" of 1883

"It is impossible not to conjecture a connection with the volcanic eruption in the Sunda Straits, by which, on Aug. 26, the island of Krakatoa disappeared wholly from the face of the earth."

"The terrible nature of this outburst can hardly be realized: the sky was darkened for several days, the noise was heard two thousand miles, magnetic disturbances were noted, the tidal wave was distinctly felt at San Francisco, and the atmospheric disturbance was sufficient to cause marked barometric fluctuations, which were noted by the barographs on the continent, in England and America, for several succeeding days."

- W. Upton, "The Red Skies." Science, 11 January 1884

During the fall of 1883 there was a remarkable atmospheric phenomenon which "attracted great attention not only from the general public, but from scientific men, who have endeavored to give a satisfactory explanation of it." At the time that he wrote those words Winslow Upton had just accepted the position of Professor of Astronomy at Brown University. Prior to this he had been Assistant Professor of Meteorology in the U.S. Signal Service from 1881. The phenomena that he endeavored to explain were the "recent fiery sunsets" seen throughout the world.

The Scream (1893) by Edvar Munch
(National Gallery, Oslo, Norway)

There were three different hypotheses as to the cause of the "blaze of brilliant red light" seen at sunset. One possibility was refraction through water vapor in the atmosphere. Another suggestion was that the Earth was passing through a cloud of meteoric dust. But the most likely explanation, as improbable as it sounded at the time, was that a large amount of dust from the eruption of the volcanic island of Krakatoa had been thrown up to such a height that it slowly spread around the globe. Microscopic examinations of residue from snow in Madrid and a rain-storm in Holland seemed to confirm the volcanic hypothesis by revealing the presence of particles that were similar in composition to the ash from Indonesia.

The sight of the blood red sky seen at sunset may even have inspired the Norwegian artist Edvar Munch who "felt a great, unending scream piercing through nature."

Note: I originally published this on the Ladd Observatory Weather Underground blog in 2011.

The summit station at El Misti, Peru (19,200 feet)

"The night is passed at the hut, and the final ascent to the summit made on the second morning. This occupies several hours, as the animal stops to rest every fifteen or twenty feet at this altitude. On two occasions I was obliged to walk a short distance to cross snow which had drifted across the path, and realized the extreme difficulty of breathing during the exertion required."

"The effect of the altitude upon me was chiefly to cause headache, sleeplessness and partial loss of appetite. On one occasion while at the summit I experienced a decided feeling of faintness for a short time."

- Winslow Upton, Physiological Effect of Diminished Air Pressure, Science, 27 December 1901

Misti summit station, Jan. 5, 1894.
Shut in by cloud [and] snow looking N. E.

During the academic year of 1896-97 Prof. Winslow Upton took sabbatical from his work as Director of Brown University's Ladd Observatory. He spent ten months at the new southern station of the Harvard College Observatory (elevation 8,050 feet) in Arequipa, Peru. His primary goal was to measure the geographical position of the station before astronomical observations could commence.

During this time he also made four ascents to the summit of the dormant volcano El Misti, which was the site of recording instruments (pictured above) maintained by Harvard. At the time it was the highest meteorological station in the world at an elevation of 19,200 feet.

Geared to the Stars

The telescope at Ladd Observatory uses a clock drive to compensate for the Earth's rotation and track the stars. Modern telescopes use electric motors but this one was built in 1891 before electric power distribution was common. The Observatory originally had gas lamps for lighting and the telegraph system was powered by "gravity cell" batteries. The telescope's mechanical clock drive is weight driven with the speed regulated by a centrifugal friction governor.

A closeup of the clock drive showing the governor in motion.
An optical sensor and precision timer are used to measure the rotation rate.

The Dawn of a New Era

When I was a young child I would watch reruns of the original Star Trek. It wasn't so much the space ships or aliens that impressed me. It was seeing human beings just simply standing on another planet that moved me. It gave me the idea that there were other worlds out there, and that you could travel beyond the Earth to visit them. That sparked my imagination.

My parents would then change the television channel and again I would see people walking on another world. But this time it was on the 6 o'clock news. A grainy video of astronauts in bulky spacesuits standing on a monochrome landscape with the crackling audio of a voice calmly saying "Beautiful, magnificent desolation." It was, arguably, one of the few moments in human history when reality was more amazing than our wildest dreams.

Six months after Apollo 13.
Photo credit: Mom, Halloween 1970.

Prismatic Analysis

One of the projects that I've been working on is the Brashear astronomical spectroscope from 1891. We're trying to recreate the ability to record spectra using the original photographic plate holder. Here is the wooden plate holder mounted in place of the eyepiece assembly that is used for visual spectroscopy.

A focusing screen was created by mounting the ground glass in a foamcore frame that fits the plate holder.

The Transits of Venus

The 2012 transit of Venus by Michael Umbricht

The June 5, 2012 transit of Venus across the Sun at 6:21:38 PM EDT captured using a modern digital camera through the historic main telescope at Ladd Observatory.

The telescope is a refractor with 12" aperture and 15' focal length. A solar pre-filter was used on the objective of the telescope and the camera used a broadband hydrogen alpha nebular filter to further reduce the brightness due to the sensitivity of the camera. The weather was mostly cloudy during the day and this image was taken during a brief thinning of the clouds which gives the Sun's surface a mottled appearance. 

The photo at left shows Michael Umbricht preparing the telescope and camera before the transit.

The Chemical Furnace

Celestial globe, late 19^th century.

This closeup image of a celestial globe shows an obsolete constellation called Machina Electrica (electrostatic generator) and Fornax Chemica (chemical furnace) which is now simply called Fornax. The latter constellation was originally named le Fourneau by La Caille in 1756 and was Latinized by him to Fornax Chimiæ in 1763. There are a variety of alternate spellings.