EARTH AT EQUINOX
Photo taken by the Russian Eleckro-L meteorological satellite courtesy of http://zelenyikot.livejournal.com/17213.html
I was astounded at the 28 September Astronomy Picture Of the Day (APOD) showing Earth at equinox. It was magnificent. Previous pictures I had seen which showed one hemisphere of Earth were actually made of many pictures pieced together from various satellite images taken on different days. This high resolution equinox picture was taken by one satellite in one photograph. It shows the Earth bathed in sunlight pole to pole.
When I requested permission to use this “Equinox Earth” photograph, I was informed by Igor Tirsky that it must be linked to http://zelenyikot.livejournal.com/17213.html, a Russian website. I was disappointed that the “English” translation button at that site would not work for me. I will keep checking back to see if that is repaired.
With the 2012 Russian discovery of Comet ISON and now this image of the Earth at equinox, the Russians are definitely popularizing Russian space efforts.
The original photograph of the Earth at equinox was edited by Vitaly Egorov of Russia. The photograph was taken from the Russian geostationary and meteorological satellite Eleckro-L which remains over the Earth’s equator 24-hours a day. From a distance of 36,000 kilometers above the equator, the satellite camera takes a picture of Earth every 30-minutes.
This equinox picture was taken on 22 September of this year (2013) when the Sun was right over the equator and the direct rays of the Sun were directed at the equator. This position of the Sun over the equator happens only twice a year, once in March and once in September. In this photograph, all of the exposed hemisphere is bathed in sunlight. The satellite was positioned exactly between the Sun and Earth when this photograph was taken.
On the equinox day every part of the Earth experiences 12-hours of daylight and 12-hours of darkness, even the polar regions. The prefix “equi-“ means equal. The postfix “-nox” means night. The literal translation of the word equinox means the “night is equal to the day.”
The Astronomy Picture Of the Day (APOD) link to that photograph is: http://apod.nasa.gov/apod/ap130928.html
The original photograph was 5000 X 5000 pixels and nearly 70-inches square. What a wall poster that would be! I had to reduce the photograph for this web publication. Even reduced, the photograph is wonderful. Definitely one to remember!
Thank you Vitaly Egorov and Igor Tirsky for the photograph.