The Great American Eclipse of  2017 August 21


Dr. Wolfgang Strickling

global map of the eclipse, calculated with eclipse2017

My actual results   Deutscher Text

          Sonnenfinsternis in EuropaOn August 21, 2017 a solar eclipse will occur  over the entire North American continent and parts of South America, the Pacific and the Atlantic Ocean. The band of totality will cross the US states Oregon, Idaho, Wyoming, Nebraska, Kansas, Missouri, Illinois, Kentucky, Tennessee, Georgia, North and South Carolina. When crossing the Oregon coastline, the Moon will cover the Sun for about 2 minutes. The duration of totality will increase the more the shadow moves eastward. At the point of maximum eclipse 50 miles west of Nashville there will occur 2 minutes and 40 seconds of totality. Afterwards the duration will decrease, but when reaching the East coast of South Carolina north of Charleston there will still remain more than 2:30.

In north-western Europe, the eclipse will only be visible as a partial eclipse, in the evening or at sunset, see map at right. Only Iceland, Scotland and Ireland will see the eclipse from beginning to end, in the the rest of the UK, Norway, the Netherlands, Belgium, France, Spain and Portugal sunset will occur before the end of the eclipse. In Germany, only in the extreme north-west the beginning of the eclipse might be visible just at sunset. In all regions east of the orange line in the map the eclipse will be invisible.

Eye safety:

During the entire eclipse, except the short moment of totality, you must protect your eyes! Use certified eclipse shades or eclipse glasses. Common sunglasses are not sufficient by far! Binoculars and telescopes must be equipped with proper filters to reduce the light. Very important: Never use eclipse shades behind a telescope ocular, because they will melt in the focused heat of the lenses! If you are in the central zone, you do not need any shades during totality, when the sky becomes completely dark as night. You can observe the corona safely with your naked eyes and even with binoculars or telescopes. But do not forget to put filters and shades on before totality is over!
To remind you for putting the eclipse glasses off and on an app on your mobile phone like Eclipse 2017 or EclipseDroid is very useful.

map USA

Map of the eclipse path over  the USA. The bold blue line is the centreline, where the totality duration will be maximal. The violet lines indicate limits of totality, outside that area the eclipse will be only visible as a partial eclipse.


A very recommended weather information page is Jay Anderson's page for the eclipse 2017  including detailed climate and cloudiness statistics tables.
In general you have to expect higher  cloudiness at the Oregon coastline, the western slopes of the rocky mountains and east of North Platte.

Details of the Eclipse

SarosportrraitScreenshot Eclipse
        2017Here are details for a place on the west coast of Sulawesi on the centreline, calculated with my  app Eclipse 2017:

Mon, 2017 - 08 - 21  total solar eclipse
Nashville, +36.162663°  -86.781601°
Altitude: 0 m
Timezone: UTC  +2.0 h,  DeltaUTC = 69.18 s

Cont hh:mm:ss.s  Alt  Azim  PA Clock
C1 : 18:58:30.3   63° 151° 294°  1.4
C2 : 20:27:26.0   64° 201° 159°  7.3
mid: 20:28:23.3   64° 202°  24° 11.8
C3 : 20:29:20.5   64° 202° 250°  4.3
C4 : 21:54:01.7   53° 237° 114°  9.7

Rise   Azim    Culm.    Set    Azim
13:10    74°   19:50   02:31   286°

Duration   : 01:54.4
Magnitude  : 1.0046  (100.5 % Diam.)
Coverage   : 100.0 % (area)
Size Ratio : 1.0306  (Ø Moon/Ø Sun)
UmbralDepth: 29.9 %
Dist. to centerline: 40 km

For details on this eclipse, the circumstances, tips how and where to observe have a look at the Android App Eclipse 2017. For calculation of other eclipses you can use AstroWin for Windows or EclipseDroid for Android. The latter is also good for controlling cameras and it is supporting sophisticated observation programs.

The Great Eclipse 2017 is part of the Saros-Period 145, which lasts from the year 1096 and will end with its eclipse number 73 in 2394. In this period there will occur every 18 years and 18 days an eclipse. It is containing 30 partial eclipses. The other 43 ones are total, with durations between 01:14 minutes up to 6:57 in the year 1565. As usually some annular or hybrid eclipses occur in a Saros period, number 130 with exclusively total or partial ones is quite remarkable. The image right is showing a Saros-snail, indicating how the lunar shadow hits the earth at the maximum of each eclipse. Click into thee image to enlarge. It was created with my Windows-software Sarosportrait.

© 2016 Dr. Wolfgang Strickling




lastUpdate: 2016-02-15