Has anyone observed the impact of the solar eclipse on twilight? I mean mostly the extension of the totality path in the atmosphere.

I mean the pattern below: enter image description here

I - normal situation with total solar eclipse happening above the horizon II - umbra meets the terminator, but the eclipse can be still visible by the observer III - something like single-limit eclipse with umbra partially coincided with the Earth's shadow IV - Eclipse is almost gone for an observer at the terminator line, but umbra still can be observed in the atmosphere V - Umbra leaves the atmosphere VI - Umbra is totally gone

I am wondering if it's anyone, who watched this phenomenon being further than the eclipse limit at sunrise or sunset. Because the twilight period including about 1500 nautical miles, any casual observer could see the impact of the eclipse in the atmosphere when the eclipse event itself isn't observed anymore (as it's geometrically below the horizon).

In general, an event such as this can be helpful in the following observations:

  • near-sun objects,
  • solar F-corona
  • twilight standstill
  • others ???

An example of one of the approaches is considered here:


I realize, that it's quite pointless traveling to the Twilight zone whereas flying just 1000km further you could enjoy a beautiful eclipse event, but... the question is predominantly for casual, local observers living in the areas, in which events such as these took place before! The impact of the solar eclipse on twilight has practically the same frequency as the solar eclipse. For example in Europe, we have forthcoming 2 events on April 8, 2024, and August 12, 2026.

The sources about this phenomenon are rather scant. I found them maybe 8-10. Including historical observations. If anyone could come up with some nice links, which would help me to carry on studying about it, that would be great!

Any photos, links, scripts, and references will be cordially appreciated if anyone was fortunate to catch an event such as this.

  • $\begingroup$ I have voted to close as I cannot find a valid question in what you have posted. Are you looking for links on this phenomenon? Do you want confirmation you aren't the only one who has seen it? Or is it just a large post with a lot of links to your blog and videos trying to self-promote? $\endgroup$
    – Rory Alsop
    Apr 19 at 17:57
  • $\begingroup$ Sorry mate, the question is in capitals beneath: HAS ANYONE OBSERVED THIS PHENOMENON BEFORE? Please read carefully. $\endgroup$
    – Geographos
    Apr 20 at 13:48
  • $\begingroup$ I think I get what you are talking about. Shortly after sunset, the sky remains "blue" as it is still in the sunlight. But if an eclipse is occurring, the part of the sky may be in the moon's shadow. And part of the sky will then appear dark, after sunset, while other parts of the sky will appear "blue" as they are still illuminated by the sun. $\endgroup$
    – James K
    Apr 20 at 17:14
  • $\begingroup$ I more aware of the "opposite" effect, where during an eclipse, the sky near the horizon is still lit by the sun even as the sky near the zenith goes dark. $\endgroup$
    – James K
    Apr 20 at 17:15
  • 1
    $\begingroup$ Sadly no one has came up with some observations, that's a pitty $\endgroup$
    – Geographos
    Apr 24 at 15:10

1 Answer 1


I have three individual observations (unfortunately just remote) of the event, in which the extension of the solar eclipse can be observed in the twilight belt. The observations I've managed to make apply to the following total solar eclipses: 2019,2020 and 2021. The most spectacular was obviously the first one, where I clearly noticed how the umbra vanishes in the Earth's atmosphere. Moreover, I could spot the coincidence of the umbra with the Belt of Venus and Earth's shadow, as the event took place after sunset.

enter image description here

enter image description here

The most curious phenomenon was the difference in scattered light at the edge of the umbra (from bluish to strong reddish), which explanation you can find here, as well as other details of this report: https://www.mkrgeo-blog.com/solar-eclipse-below-the-horizon-2019-the-worlds-first-webcam-observation/

In another case, I wasn't such fortunate as previously due to the webcams, which weren't recorded in live mode but only refreshed every 15 sec. Moreover, the one located close to the extended path was rotated, so I could effectively make the view of the same scene every 45s. I've collected the image below including the potential situation at the greatest eclipse. enter image description here

There were quite a lot of other observations at the same time, although they refer just to the partial phase of the eclipse. The details you can read here: https://www.mkrgeo-blog.com/total-solar-eclipse-2020-remote-chasing-the-umbra-and-a-brief-explanation-how-do-the-webcams-work/

Finally, I managed to capture the umbra passing inside of the Earth's shadow at solar depression over 4 degrees on December 2021. Stanley (Falkland Islands) - total solar eclipse below the horizon - view at the antisolar direction - 4 degrees below the horizon Unfortunately, the common denominator was poor webcams, especially the last ones. Regardless of the image quality I managed to prepare the nomograph presenting the impact of the solar eclipse on the twilight. enter image description here

Some YT records here:


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