What’s it like to see a total solar eclipse?


Fred Espenak – aka Mr. Eclipse – captured this self-portrait during the fleeting moments of totality at a 2006 total solar eclipse.

The great American total eclipse of the sun is now just three months away.

Those of us who have witnessed totality (that brief period when the the sun’s brilliant disk is completely hidden, revealing its glorious corona) realize how monumentally difficult it is to convey that experience to others. Words often fail when trying to explain the kaleidoscope of sights, sounds, feelings and emotions that consume us during this other-worldly event.

A series of nine images were combined into a time sequence of the total solar eclipse of August 11, 1999 from Lake Hazar, Turkey. The corona has been computer enhanced to show subtle details and prominences. Copyright 1999 by Fred Espenak. Used with permission.

The best description I’ve ever read of the experience of totality was written over a century ago by Mabel Loomis Todd in her book Total Eclipses of the Sun, 1894. Todd was an American writer and editor who traveled to a number of total eclipses with her husband astronomer David Peck Todd during the late 19th century.

Her description is not only expressive and passionate, but it accurately captures the variety and sequence of events in a most compelling way:

As the dark body of the moon gradually steals its silent way across the brilliant sun, little effect is at first noticed. The light hardly diminishes, apparently, and birds and animals detect no change.

During the partial phase a curious appearance may be noticed under any shade tree. Ordinarily, without an eclipse, the sunlight filters through the leaves in a series of tiny, overlapping disks on the ground, each of which is an image of the sun. But when the partial phase of an eclipse is well advanced, these sunny spots become crescent in form, images of the now narrowing sun.

The gaps between the leaves on a tree act like a series pinhole cameras that each project an image of the eclipse sun on the ground below. Image from Mabel Loomis Todd’s Total Eclipses of the Sun, 1894, via Fred Espenak.

As the entire duration of an eclipse, partial phases and all, embraces two or three hours, often for an hour after ‘first contact’ insects still chirp in the grass, birds sing, and animals quietly continue their grazing. But a sense of uneasiness seems gradually to steal over all life. Cows and horses feed intermittently, bird songs diminish, grasshoppers fall quiet, and a suggestion of chill crosses the air. Darker and darker grows the landscape.

As much as five minutes before total obscurity it may be possible to detect strange wavering lines of light and shade dance across the landscape – the ‘shadow bands’ as they are called – a curious and beautiful effect (related to the same atmospheric phenomenon that causes stars to twinkle).

Shadow bands are seen to ripple across a house in Sicily during a total eclipse in 1870. Image from Mabel Loomis Todd’s Total Eclipses of the Sun, 1894, via Fred Espenak.

Then, with frightful velocity, the actual shadow of the moon is often seen approaching, a tangible darkness advancing almost like a wall, swift as imagination, silent as doom. The immensity of nature never comes quite so near as then, and strong must be the nerves not to quiver as this blue-black shadow rushes upon the spectator with incredible speed. A vast, palpable presence seems to overwhelm the world. The blue sky changes to gray or dull purple, speedily becoming more dusky, and a death-like trance seizes upon everything earthly. Birds with terrified cries, fly bewildered for a moment, and then silently seek their night quarters. Bats emerge stealthily. Sensitive flowers, the scarlet pimpernel, the African mimosa, close their delicate petals, and a sense of hushed expectancy deepens with the darkness.

An assembled crowd is awed into silence almost invariably. Trivial chatter and senseless joking cease. Sometimes the shadow engulfs the observer smoothly, sometimes apparently with jerks; but all the world might well be dead and cold and turned to ashes. Often the very air seems to hold its breath for sympathy; at other times a lull suddenly awakens into a strange wind, blowing with unnatural effect.

Then out upon the darkness, gruesome but sublime, flashes the glory of the incomparable corona, a silvery, soft, unearthly light, with radiant streamers, stretching at times millions of uncomprehended miles into space, while the rosy, flame-like prominences skirt the black rim of the moon in ethereal splendor. It becomes curiously cold, dew frequently forms, and the chill is perhaps mental as well as physical.

A composite image of the total solar eclipse of 2006 March 29 was shot in Jalu, Libya. It was produced from 26 individual exposures obtained with two separate telescopes and combined with computer software to reveal subtle details in the corona. Copyright 2006 by Fred Espenak. Used with permission.

Allow me to interject here for a moment. Totality never lasts more than 7 and 1/2 minutes. But this is exceedingly rare and will not happen again until 2186. It is far more common for totality to last a mere 2 or 3 minutes, and this is the case for the 2017 eclipse. Although the corona appears static (no visible motion) during this brief interval, it is never-the-less mesmerizing in its delicate gossamer beauty. This million-degree plasma is electrically charged and twisted by the intense magnetic fields of the Sun into a complex array of streamers, plumes, brushes, and loops. All of this surrounds the jet-black disk of the Moon appearing as an eerie hole in the heavens.

Many inexperienced writers often say that “day turns to night”, but the darkness of totality more closely resembles evening twilight when the first stars become visible. The colors of sunset/sunrise ring the horizon as you look out the edge of the lunar shadow into locations still bathed in sunlight. And the brightest planets are visible to the naked eye. In the case of 2017, Venus and Jupiter will easily be seen.

The eerie twilight of totality is seen against a backdrop of thorn acacia trees in this wide-angle photograph shot during the total solar eclipse of 2001 June 21 from Chisamba, Zambia. Copyright 2001 by Fred Espenak. Used with permission.

Although these sights are all impressive, the eye is invariably drawn back to the corona and its apparition-like appearance and exquisite detail.

Todd’s description of the end of totality continues:

Suddenly, instantaneously as a lightning flash, an arrow of actual sunlight strikes the landscape, and Earth comes to life again, while the corona and prominences melt into the returning brilliance, and occasionally the receding lunar shadow is glimpsed as it flies away with the tremendous speed of its approach.
The great opportunity has come and gone, and happy is the astronomer who has kept the poetry of his nature in such abeyance that the merely accurate and scientific work has been accomplished; but in executing his prescribed program, the professional observer must exercise vast self-control.

Professor Langley says of this superb sight: ‘The spectacle is one of which, though the man of science may prosaically state the facts, perhaps only the poet could render the impression.’

I doubt if the effect of witnessing a total eclipse ever quite passes away. The impression is singularly vivid and quieting for days, and can never be wholly lost. A startling nearness to the gigantic forces of nature and their inconceivable operation seems to have been established. Personalities and towns and cities, and hates and jealousies, and even mundane hopes, grow very small and very far away.

As totality ends, the Sun begins to emerge from behind the Moon producing the dazzling diamond ring effect. Copyright 2016 by Fred Espenak. Used with permission.

Totality – The Great America Eclipses of 2017 and 2024, my newly published book with Mark Littmann has a unique feature called “Moments of Totality.” These are personal anecdotes and stories shared by people who have witness totality themselves. A separate “Moment of Totality” appears after each chapter in the book adding many different voices to this topic.

Please share this post with anyone who is still unsure about whether a trip to the 2017 path of totality is worth the effort.



from EarthSky http://ift.tt/2sk9YCl

Fred Espenak – aka Mr. Eclipse – captured this self-portrait during the fleeting moments of totality at a 2006 total solar eclipse.

The great American total eclipse of the sun is now just three months away.

Those of us who have witnessed totality (that brief period when the the sun’s brilliant disk is completely hidden, revealing its glorious corona) realize how monumentally difficult it is to convey that experience to others. Words often fail when trying to explain the kaleidoscope of sights, sounds, feelings and emotions that consume us during this other-worldly event.

A series of nine images were combined into a time sequence of the total solar eclipse of August 11, 1999 from Lake Hazar, Turkey. The corona has been computer enhanced to show subtle details and prominences. Copyright 1999 by Fred Espenak. Used with permission.

The best description I’ve ever read of the experience of totality was written over a century ago by Mabel Loomis Todd in her book Total Eclipses of the Sun, 1894. Todd was an American writer and editor who traveled to a number of total eclipses with her husband astronomer David Peck Todd during the late 19th century.

Her description is not only expressive and passionate, but it accurately captures the variety and sequence of events in a most compelling way:

As the dark body of the moon gradually steals its silent way across the brilliant sun, little effect is at first noticed. The light hardly diminishes, apparently, and birds and animals detect no change.

During the partial phase a curious appearance may be noticed under any shade tree. Ordinarily, without an eclipse, the sunlight filters through the leaves in a series of tiny, overlapping disks on the ground, each of which is an image of the sun. But when the partial phase of an eclipse is well advanced, these sunny spots become crescent in form, images of the now narrowing sun.

The gaps between the leaves on a tree act like a series pinhole cameras that each project an image of the eclipse sun on the ground below. Image from Mabel Loomis Todd’s Total Eclipses of the Sun, 1894, via Fred Espenak.

As the entire duration of an eclipse, partial phases and all, embraces two or three hours, often for an hour after ‘first contact’ insects still chirp in the grass, birds sing, and animals quietly continue their grazing. But a sense of uneasiness seems gradually to steal over all life. Cows and horses feed intermittently, bird songs diminish, grasshoppers fall quiet, and a suggestion of chill crosses the air. Darker and darker grows the landscape.

As much as five minutes before total obscurity it may be possible to detect strange wavering lines of light and shade dance across the landscape – the ‘shadow bands’ as they are called – a curious and beautiful effect (related to the same atmospheric phenomenon that causes stars to twinkle).

Shadow bands are seen to ripple across a house in Sicily during a total eclipse in 1870. Image from Mabel Loomis Todd’s Total Eclipses of the Sun, 1894, via Fred Espenak.

Then, with frightful velocity, the actual shadow of the moon is often seen approaching, a tangible darkness advancing almost like a wall, swift as imagination, silent as doom. The immensity of nature never comes quite so near as then, and strong must be the nerves not to quiver as this blue-black shadow rushes upon the spectator with incredible speed. A vast, palpable presence seems to overwhelm the world. The blue sky changes to gray or dull purple, speedily becoming more dusky, and a death-like trance seizes upon everything earthly. Birds with terrified cries, fly bewildered for a moment, and then silently seek their night quarters. Bats emerge stealthily. Sensitive flowers, the scarlet pimpernel, the African mimosa, close their delicate petals, and a sense of hushed expectancy deepens with the darkness.

An assembled crowd is awed into silence almost invariably. Trivial chatter and senseless joking cease. Sometimes the shadow engulfs the observer smoothly, sometimes apparently with jerks; but all the world might well be dead and cold and turned to ashes. Often the very air seems to hold its breath for sympathy; at other times a lull suddenly awakens into a strange wind, blowing with unnatural effect.

Then out upon the darkness, gruesome but sublime, flashes the glory of the incomparable corona, a silvery, soft, unearthly light, with radiant streamers, stretching at times millions of uncomprehended miles into space, while the rosy, flame-like prominences skirt the black rim of the moon in ethereal splendor. It becomes curiously cold, dew frequently forms, and the chill is perhaps mental as well as physical.

A composite image of the total solar eclipse of 2006 March 29 was shot in Jalu, Libya. It was produced from 26 individual exposures obtained with two separate telescopes and combined with computer software to reveal subtle details in the corona. Copyright 2006 by Fred Espenak. Used with permission.

Allow me to interject here for a moment. Totality never lasts more than 7 and 1/2 minutes. But this is exceedingly rare and will not happen again until 2186. It is far more common for totality to last a mere 2 or 3 minutes, and this is the case for the 2017 eclipse. Although the corona appears static (no visible motion) during this brief interval, it is never-the-less mesmerizing in its delicate gossamer beauty. This million-degree plasma is electrically charged and twisted by the intense magnetic fields of the Sun into a complex array of streamers, plumes, brushes, and loops. All of this surrounds the jet-black disk of the Moon appearing as an eerie hole in the heavens.

Many inexperienced writers often say that “day turns to night”, but the darkness of totality more closely resembles evening twilight when the first stars become visible. The colors of sunset/sunrise ring the horizon as you look out the edge of the lunar shadow into locations still bathed in sunlight. And the brightest planets are visible to the naked eye. In the case of 2017, Venus and Jupiter will easily be seen.

The eerie twilight of totality is seen against a backdrop of thorn acacia trees in this wide-angle photograph shot during the total solar eclipse of 2001 June 21 from Chisamba, Zambia. Copyright 2001 by Fred Espenak. Used with permission.

Although these sights are all impressive, the eye is invariably drawn back to the corona and its apparition-like appearance and exquisite detail.

Todd’s description of the end of totality continues:

Suddenly, instantaneously as a lightning flash, an arrow of actual sunlight strikes the landscape, and Earth comes to life again, while the corona and prominences melt into the returning brilliance, and occasionally the receding lunar shadow is glimpsed as it flies away with the tremendous speed of its approach.
The great opportunity has come and gone, and happy is the astronomer who has kept the poetry of his nature in such abeyance that the merely accurate and scientific work has been accomplished; but in executing his prescribed program, the professional observer must exercise vast self-control.

Professor Langley says of this superb sight: ‘The spectacle is one of which, though the man of science may prosaically state the facts, perhaps only the poet could render the impression.’

I doubt if the effect of witnessing a total eclipse ever quite passes away. The impression is singularly vivid and quieting for days, and can never be wholly lost. A startling nearness to the gigantic forces of nature and their inconceivable operation seems to have been established. Personalities and towns and cities, and hates and jealousies, and even mundane hopes, grow very small and very far away.

As totality ends, the Sun begins to emerge from behind the Moon producing the dazzling diamond ring effect. Copyright 2016 by Fred Espenak. Used with permission.

Totality – The Great America Eclipses of 2017 and 2024, my newly published book with Mark Littmann has a unique feature called “Moments of Totality.” These are personal anecdotes and stories shared by people who have witness totality themselves. A separate “Moment of Totality” appears after each chapter in the book adding many different voices to this topic.

Please share this post with anyone who is still unsure about whether a trip to the 2017 path of totality is worth the effort.



from EarthSky http://ift.tt/2sk9YCl

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