Few are aware of the imminent cosmic phenomenon that sweeps all across USA in its splendor and rarity—the wonder of total solar eclipse. August 21st of this year will mark its occurrence after a void of almost 100 years, when it had painted the entire nation in the year 1918 (In the year 1979 it touched a tiny spot in the northern USA before veering off northbound). The whole effort of this year’s annual ASP (Astronomical Society of the Pacific) meeting was to spread out the word, engage as many science followers as possible into the majesty of this celestial display; urge them on into once in a lifetime kind of show.
There were stimulating talks disseminating the scientific background, and the enormous efforts that have been put in to popularize, educate, and incite on the appearance and experience of a total solar eclipse itself. And the ASP plans to upload all the talks on their website, in the hope to spur on a wider enthusiasm and interest. Here is some useful set of information to help you prepare and indulge if you feel interested: NASA (1), Being in the Shadow (2), Great American Eclipse (3).
I being an ardent proponent of the physical sciences indeed tuned in, and pitched my own take on the subject of total solar eclipse, and how this phenomenon has played a vital role in revealing the basic principles of how the universe structures and continues. So here is my talk—The Eclipse that Changed the Picture of the Universe—at the meeting, in case you feel inspired.
Total solar eclipse takes place when the earth, moon and sun together strike a perfect alignment such that the moon situated in the middle fully blocks out the sun for a brief moment in space and time, leaving out the halo of corona—the usually invisible sun’s outer atmosphere—a brilliant ring that glows from behind. For that brief period we remain under the shadow of the moon while the radiating corona flags the sun’s only identity in the sky. It is the only instance in time when although the sun is present in our view of the sky, its intense glare remains occluded. Albert Einstein around the year 1915 realized that this relatively rare instance gives us an astonishing window into the nature of reality. How? In the year 1915 Einstein had proposed—by his theory of general relativity—that spacetime conforms to the force of gravity. Simply, gravity gives geometry to the universe. And if this is true then matter bends light.
An event of a total solar eclipse extends us a perfect window into which we can verify such bending of the light. The ultra bending of the light reaches a detection level only when caused by a massive cosmic body, such as sun. The bending of the light by the sun is ascertained by measuring the shifts in the positions of the background stars—the deflections of stars as the sun passes through (Picture 1). Measured in arcseconds—an extraordinarily miniscule amount—this deflection, however, would be impossible to pin down due the intense glare of sun on a usual day. The event of a total solar eclipse thus gives us a perfect window for studying sun’s gravitational field without being bedazzled by the blinding glow.
The total solar eclipse of May 29, 1919, became a legendary eclipse (Picture 2) that attested the bending of light by matter, theorized by Einstein. The discovery of spacetime curvation by the force of gravity led us to a bigger and finer picture of the universe: From the way the universe might have begun to the existence of black holes to theory of wormhole to the pulsation of gravitational waves, recently detected by LIGO (Laser Interferometer Gravitational-Wave Observatory).
The new picture emerged, and Einstein celebrated, by the mechanics of the natural grandeur.