TOTAL SOLAR ECLIPSE 2017 WHEN, WHERE AND HOW TO SEE IT (SAFELY)
By SPACE.com
On Aug. 21, 2017, people across the United States will see the sun disappear behind the
moon, turning daylight into twilight, causing the temperature drop rapidly and revealing
massive streamers of light streaking through the sky around the silhouette of the moon.
On that day, America will fall under the path of a total solar eclipse .
The so-called Great American Total Solar Eclipse will darken skies all the way from Oregon
to South Carolina, along a stretch of land about 70 miles (113 kilometers) wide.
People who descend upon this �path of totality� for the big event are in for an unforgettable
experience.
Here is Space.com�s complete guide to the 2017 total solar eclipse.
It includes information about where and when to see it, how long it lasts, what you can
expect to see, and how to plan ahead to ensure you get the most out of this incredible experience.
Update 7/19: Don�t forget to check out all our most recent articles about the total solar
eclipse, including tips on where and how to see it.About why sunglasses won�t cut it
when you�re viewing a solar eclipse, plus a video about how to make your own solar eclipse
viewer.
REMEMBER: Looking directly at the sun, even when it is partially covered by the moon,
can cause serious eye damage or blindness.
NEVER look at a partial solar eclipse without proper eye protection . See our complete guide
to find out how to view the eclipse safely.
WHAT IS A TOTAL SOLAR ECLIPSE?
A total solar eclipse occurs when the disk of the moon appears to completely cover the
disk of the sun in the sky.
The fact that total solar eclipses occur at all is a quirk of cosmic geometry.
The moon orbits an average of 239,000 miles (385,000 kilometers) from Earth � just the
right distance to seem the same size in the sky as the much-larger sun.
However, these heavenly bodies line up only about once every 18 months.
Outside the path of totality, skywatchers in the continental U.S. and other nearby areas
will see a partial solar eclipse, in which the moon appears to take a bite out of the
sun�s disk.
Two to five solar eclipses occur each year on average, but total solar eclipses happen
just once every 18 months or so.
WHAT WILL I SEE DURING A TOTAL SOLAR ECLIPSE?
During a total solar eclipse, the disk of the moon blocks out the last sliver of light
from the sun, and the sun�s outer atmosphere, the corona, becomes visible.
The corona is far from an indistinct haze; skywatchers report seeing great jets and ribbons
of light, twisting and curling out into the sky.
�It brings people to tears,� Rick Fienberg, a spokesperson for the American Astronomical
Society (AAS), told Space.com of the experience.
�It makes people�s jaw drop.�
During totality, the area inside the moon�s shadow is cloaked in twilight � a very strange
feeling to experience in the middle of the day.
Just before and just after totality, observers can see this cloak of darkness moving toward
them across the landscape, and then moving away.
These effects are not visible during a partial solar eclipse, so skywatchers are encouraged
to see if they are inside the path of totality during the total eclipse.
FROM WHAT LOCATIONS WILL THE TOTAL SOLAR ECLIPSE BE VISIBLE?
The path of totality for the Aug. 21, 2017, total solar eclipse is about 70 miles wide
and stretches from Oregon to South Carolina.
It passes through Idaho, Wyoming, Nebraska, Kansas, Missouri, Illinois, Kentucky, Tennessee,
Georgia, North Carolina and South Carolina.
You can use this interactive map from NASA to zoom in on the path and find out the exact
locations from which it will be visible.
You can also check out our state-by-state guide to find out which major cities and prime
locations will fall inside the path of totality.
You may also want to attend one of the many eclipse parties and organized events taking
place around the path of totality.
WHEN WILL THE TOTAL SOLAR ECLIPSE OCCUR, AND HOW LONG WILL IT LAST?
The timing of the total solar eclipse and its duration both depend on where you are
inside the path of totality.
At most, the moon will completely cover the disk of the sun for 2 minutes and 40 seconds.
That�s about how long totality will last for observers positioned anywhere along the
center of the path of totality.
As you move toward the edge of the path, the duration of totality will decrease.
People standing at the very edge of the path may observe totality for only a few seconds.
The chart below lists the moment of mid-totality and the duration of totality for a handful
of cities that lie close to the center of the path.
Data from NASA.
Eclipse Begins Totality Begins Totality Ends Eclipse Ends
Madras, OR 09:06 a.m. 10:19 a.m. 10:21 a.m. 11:41 a.m. PDT
Idaho Falls, ID 10:15 a.m. 11:33 a.m. 11:34 a.m. 12:58 p.m. MDT
Casper, WY 10:22 a.m. 11:42 a.m. 11:45 a.m. 01:09 p.m.
MDT Lincoln, NE 11:37 a.m. 01:02 p.m. 01:04 p.m.
02:29 p.m. CDT Jefferson City, MO 11:46 a.m. 01:13 p.m. 01:15
p.m. 02:41 p.m. CDT Carbondale, IL 11:52 a.m. 01:20 p.m. 01:22
p.m. 02:47 p.m. CDT Paducah, KY 11:54 a.m. 01:22 p.m. 01:24 p.m.
02:49 p.m. CDT Nashville, TN 11:58 a.m. 01:27 p.m. 01:29
p.m. 02:54 p.m. CDT Clayton, GA 01:06 p.m. 02:35 p.m. 02:38 p.m.
04:01 p.m. EDT Columbia, SC 01:03 p.m. 02:41 p.m. 02:44 p.m.
04:06 p.m. EDT Because the shadow of the moon will move from
west to east, totality will occur later in the day the farther east you travel.
Use the NASA interactive eclipse map to find out exactly when totality will occur and how
long it will last in the location where you plan to observe the eclipse.
Just click on a spot on the map, and an informational box will appear with specific times.
DO I NEED ANY EQUIPMENT TO VIEW THE ECLIPSE?
Anyone planning to view the total solar eclipse of 2017 should get a pair of solar viewing
glasses.
These protective shades make it possible for observers to look directly at the sun before
and after totality.
The following four companies sell eclipse glasses that meet the international standard
(ISO 12312-2) recommended by NASA, the AAS and other scientific organizations: Rainbow
Symphony, American Paper Optics, Thousand Oaks Optical and TSE 17.
Sunglasses cannot be used in place of solar viewing glasses.
REMEMBER: Looking directly at the sun, even when it is partially covered by the moon,
can cause serious eye damage or blindness.
NEVER look at a partial solar eclipse without proper eye protection.
See our complete guide to find out how to view the eclipse safely.
During totality, when the disk of the sun is completely covered by the moon, it is safe
to look up at the celestial sight with the naked eye.
(See our in-depth safety guide for more details about when it is safe to view the eclipse
with unaided eyes.)
Binoculars are helpful for seeing more detail in the solar corona.
Telescopes are not necessary, but some skywatchers may use low-powered telescopes.
Skywatchers outside the path of totality will still be able to see a partial solar eclipse.
Solar viewing glasses allow skywatchers to look directly at the moon�s progress across
the face of the sun.
You can also view the progress of a partial solar eclipse using a pinhole camera.
For more information, see our complete guide for how to view the eclipse safely.
WHAT ELSE SHOULD I KNOW BEFORE VIEWING THE ECLIPSE?
Aug. 21, 2017, may be one of the worst traffic days in national history, some NASA representatives
predict.
Although about 12 million people live within the narrow band of totality, approximately
25 million reside within a day�s drive of it, and the agency has estimated that the
population inside the path of totality may double on the day of the eclipse.
With that in mind, make sure you plan for extra travel time, especially on the day of
the eclipse.
Most hotel rooms inside the path of totality have been booked for months or years, so you
may not be able to stay inside the path the night before.
When selecting a location where you plan to view the eclipse, keep in mind your proximity
to food, water, parking and facilities.
Attending an organized eclipse event is an ideal way to make sure those things are close
by.
Traveling even short distances could be difficult in some areas, and midday in the middle of
August can mean punishing heat in many parts of the country.
WHEN IS THE NEXT TIME A TOTAL SOLAR ECLIPSE WILL BE VISIBLE FROM THE U.S.?
In 2024, a total solar eclipse will darken the skies above Mexico and Texas, up through
the Midwest and northeastern U.S.
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