
Taken near the entrance of Hawai`i Volcanoes National Park (which is now closed) on May 15, 2018, at 11:28 am.
MORTON GNEISS
Morton, Minnesota
Oldest Rock in the United States — 3.524 billion years old
MORTON GNEISS
Morton, Minnesota
Oldest Rock in the United States — 3.524 billion years old
Kilauea Volcano
10 Questions About the Earth—
and the Geology of North America.
Science — History — Biography
ECLIPSES
They have been thought of as harbingers of evil as well as a sign of the divine.
Eclipses—one of the most stunning celestial events that can be witnessed on Earth—have shaped the course of history and thought since humans first turned their eyes to the sky.
THE GREAT NORTH AMERICAN
TOTAL SOLAR ECLIPSE
APRIL 8, 2024

The next total solar eclipse visible from North America will occur on April 8, 2024. Totality will be visible along a band that runs from Texas to Maine.
The longest duration of totality for this eclipse will be 4 min 26 sec in southern Texas.
Types of Solar Eclipses

PARTIAL SOLAR ECLIPSE
The Moon does not pass directly in front of the Sun.

ANNULAR SOLAR ECLIPSE
The Moon is too small to obscure the Sun completely.

TOTAL SOLAR ECLIPSE
The Moon completely obscures the Sun.
THE NEXT TOTAL LUNAR ECLIPSE:
November 8, 2022

(from NASA)
The next total lunar eclipse will be on Tuesday, November 8, 2022. It will be visible across the entire Pacific basin and most of eastern Asia and Australia. From North America it will be visible during the early morning hours. In the Hawaiian Islands, the eclipse will begin on November 7.
MASK OF THE SUN
What do Virginia Woolf, the rotation of hurricanes, Babylonian kings and Einstein's Theory of General Relativity have in common? Eclipses.
Always spectacular and, today, precisely predictable, eclipses have allowed us to know when the first Olympic games were played and, long before the first space probe was launched, that the Moon was covered by a layer of dust.
Eclipses are mentioned in Homer's Iliad and Odyssey and eight times in the Bible. The ancient Romans thought it was a bad idea to have sexual intercourse during an eclipse, while people in the South Pacific encouraged it.
Mask of the Sun explains why and how eclipses occur—and why the number 177 is important in eclipse prediction—and gives insight into the forthcoming total solar eclipse of 2017 that will be visible across the United States.

MASK of the SUN
The Science, History
and Forgotten Lore of Eclipses


Hardcover, 272 pages
Editorial reviews:
. . . expansive look at how eclipses have been mythologized throughout history . . .
—The New York Times, Concepción de León
. . . a rich chronicle . . .
—Nature, Jay Pasachoff, Field Memorial Professor of Astronomy, Williams College
Revealing the humanism behind the science of lunar and solar eclipses, Dvorak explains with insightful detail and vivid prose how and why eclipses occur, and provides insight into the total solar eclipse coming in summer 2017.
—Publisher's Weekly, Alex Crowley, Top Ten Science Books, Spring 2017
Dvorak explains complex scientific ideas succinctly and clearly without resorting to formula or jargon . . . he does an excellent job of conveying the wonder of eclipses, describing both their historical-cultural value and the inspirational effect they have on people . . . A splendid introduction to all aspects of eclipses; for all readers interested in science.
—Library Journal (starred review), Cate Hirschbiel, Iwasaki Library, Emerson College, Boston
Dvorak is a worthy narrator who has an eye for detail, and does an excellent and inspirational job of portraying the fascination that eclipses hold for those who are lucky enough to witness them.
—BBC Sky at Night, Brian Jones, author of The Practical Astronomer
Mask of the Sun charts the history of this [eclipse] obsession through dozens of stories and anecdotes that illustrate how deeply embedded eclipse lore is in cultures of the world.
—The Spectator, Marek Kukula, Royal Observatory in Greenwich
. . . meticulously researched . . . well rounded, entertaining and authoritative . . .
—The Amazon Book Review, Jon Foro
. . . a book about human endeavour to understand the heavens above us, and the meaning of celestial events . . . a thoroughly comprehensive guide to the science and history of eclipses . . .
—Magnoia Review of Books, Kevin Murphy
One need not be an eclipse-hunter, nor a stargazer, nor a scientist of any sort to be enthralled by this book. . . . a spellbinding book . . .
—Providence Journal, Phyllis Meras
. . . a deeper dive into the history of eclipse observations . . . entertaining . . .
—Wall Street Journal, Alan Hirshfeld, University of Massachusetts, Dartmouth
. . . fascinating . . .
—Times Literary Supplement (London), Owen Gingerich, Professor of Astronomy, Harvard
. . . a wealth of interesting tidbits and cogent explanations of the mechanics behind these beautiful natural phenomena.
—Irish Independent, Dublin