Edison’s “Tasimeter” and the Eclipse of 1878
On July 29, 1878, Thomas Edison observed the total eclipse of the Sun as part of Henry Draper’s Expedition to Rawlins, Wyoming Territory. (Although this year’s total eclipse will pass through Wyoming, the City of Rawlins will be some distance south of the total path this time.) Edison was there to test a new invention that could detect infrared light and estimate the temperature of objects remotely, and he planned to try and estimate the heat of the Sun’s corona while the solar photosphere was blocked by the Moon.
The Total Solar Eclipse of 2017 in SciDome
The appearance of a total solar eclipse is so singular that it is impossible to appreciate it without having seen it for oneself. Unexpected eclipses have changes history in the past, although they can now be predicted. Even having an eclipse forecast in hand does not...
Great Comet of 1811 (1812?)
The May issue of Sky and Telescope magazine has a timely item about "Napoleon's Comets". The most important of these was the Great Comet of 1811, which was the brightest comet with the longest duration of brightness on record (260 days) until Comet Hale-Bopp shattered...
Ben Franklin’s Birthday and the Gregorian Calendar
Today is Benjamin Franklin's birthday under the calendar we use today, although he was born on the 6th of January of 1706. He was born before the Gregorian calendar reform was implemented in the English-speaking world. The Gregorian calendar reform adjusted the way...
Messier Mischief
What's Up with the Pleiades Being M45? During a recent planetarium conference session, an interesting question came up about why the Pleiades is listed as M45 in Messier's catalog. Few people know the reason for it. Charles Messier is best known for his list of some...
Epicycles and Discovering Bad Theories
Our ancestors were highly intelligent people who devised ingenious methods to model what they perceived to be reality in the skies. Unfortunately, they came at many of these observations with deep-rooted prejudices and a priori (preconceived) beliefs which shackled...
Equinox: The Big Dipper Star Clock
The pointer stars Merak and Dubhe point at Polaris and go once around per sidereal day, every 23 hours 56 minutes and 4 seconds. By making a daily correction it is possible to estimate the time at night using these three stars. One point on this is pretty much...
Exploring Roemer’s Method for Determining the Speed of Light
In the 17th century the speed of light was unknown, and scientists questioned whether it had a finite value. Descartes argued that if the speed of light was finite, when we looked out into space with telescopes we’d be looking into the past. That idea was so...
Recreating Jupiter’s Galilean Moons in SciDome
In many of our astronomy classes, we discuss the importance of Galileo’s first telescopic observations in eventually overthrowing the Ptolemaic geocentric system. His first observations were relayed to the public in his short book Sidereus Nuncius, which is Latin for...
Tides Revisited and Explained
A historical lesson in Volume 2 of the Fulldome Curriculum is the astronomical aspect of the Boston Tea Party. As we learn, Colonists, furious at the tea tax, tossed chests of tea into Boston Harbor on the night of December 16, 1773. Eyewitnesses noted that the chests...
Spitz Fulldome Curriculum – Volume 2
After years of development, Volume 2 of the Spitz Fulldome Curriculum has been released as a free supplement to all SciDome sites. The curriculum covers a wide gamut of subjects (see contents in sidebar) and gives educators a new library of slides, animations, and...
Fundraising for Digital Planetariums
Planetarium technology isn’t the only thing that’s changed from the last heyday of planetarium installations in the '60s and '70s. 21st century fundraising is also a new concern for today’s educational planetariums. Today, a planetarium upgrade (or construction of a...
American History in the Planetarium
Some of the richest resources of astronomical events and history are the articles of Dr. Donald W. Olson of Texas State University at San Marcos. He has written on an incredible number of topics, including this subject, published in the March 1998 issue of Sky and...
Saving the Arlington Planetarium – A Fundraising Success Story
We often hear about planetariums closing or cutting back due to lack of funding. The David M. Brown Planetarium in Arlington Virginia was one of them, until a group of local advocates got involved and launched an effort to save their local planetarium. They were so...
Using Distance Spheres for Illustrating Stars, Black Holes, and the Speed of Light
Distance Spheres included in Starry Night allow “Cosmic Zoom” sequences in our domes. However, I also use them to show audiences scale sizes of stars, the Milky Way’s supermassive black hole, and the speed of light. In a previous article I described the upcoming...