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points by bajard 1 day ago | 0 comments
Why do most (almost all) images of Earth have Africa in front? Are they stock photos? Is it because only the Sahara Desert is frequently visible?
[–] xandrius 1 day ago
Dunno, maybe the person/team are from Europe? Or maybe if you center it on Asia or the Americas you get a side full of just ocean?
[–] jlhawn 1 day ago
This image is from a geostationary weather satellite operated primarily to monitor weather over Europe. Geostationary satellites must orbit directly above the equator at 0 degrees latitude. Because Europe and Africa share roughly the same longitudes, a geostationary satellite over Europe's longitudes places it directly over the African continent. If an orbit were inclined to center over higher latitudes like Europe, the satellite would trace a figure-eight pattern relative to the ground (called a geosynchronous orbit rather than a geostationary orbit). You are also correct about the Sahara the descending air in that subtropical high-pressure zone suppresses cloud formation, making North Africa one of the most consistently clear and recognizable land features in view from orbit.

also, perhaps the most famous image of Earth from space is "The Blue Marble" [1] taken from Apollo 17 on its way to the moon. It just happened to be located over Africa as its altitude above Earth was ideal for taking a high-res full-disk photograph. Many of the other early full-color photos of the Earth from space [2] also feature South America and the Amazon which is located near the equator. These places are going to be well-lit by the sun no matter what time of the year.

[1] https://en.wikipedia.org/wiki/The_Blue_Marble [2] https://en.wikipedia.org/wiki/Timeline_of_first_images_of_Ea...

[–] peri-cl 1 day ago
This is the right answer. It's a European GEO satellite that's approaching its assigned longitude of 9.5° East (~ Germany). This is more or less the only viewpoint of Earth it will *ever* have; that's how geosync works.

https://www.esa.int/articles/about-us/directorates/earth-obs...

https://en.wikipedia.org/wiki/Geosynchronous_orbit

Here's a table of (I think?) all of the GEO weather satellites and their positions,

https://space.oscar.wmo.int/satellitestatuses/status

(If you follow up on any of these, you can find real-time views of the Earth from different vantage points).

[–] matja 1 day ago
It's just the default (0,0) latitude/longitude