EVERYONE ON HERE: OMG Twitter is so depressing and horrible and itโ€™s full of hate OMG itโ€™s so sickening I hate it

MY TWITTER FEED:

The Sahara contains several archaeological sites featuring rock art, from several time periods dating back as far as 12000 years. Some of the finest are found in Tassili n'Ajjer national park in Algeria.

As well as showing animals which used to live in the Sahara back when it was still green, including elephants and giraffes, the rock art also shows scenes from people's daily lives, giving us views of ancient North African culture!

Show thread

Optical Illusions 

These are concentric circles. None of these lines cross over each other.

Show thread

Optical Illusions 

These two letters are the same colour.

(This may be another illusion which not everyone can see)

Show thread

Optical Illusions 

This image does not really bulge outwards, and those lines are all perfectly straight

Show thread

Optical Illusions 

There is no spiral in this image. These are concentric circles.

Show thread

This is Deinococcus radiodurans. These bacteria may be the toughest organisms in the world, surviving dehydration, cold, acid, and vacuum, and withstanding more radiation than probably any other living thing.

Some scientists have considered using them as a way of storing data to survive an apocalypse. In 2003, researchers encoded the song It's A Small World into DNA, engineered it into D. radiodurans, and managed to retrieve it without errors 100 generations later.

That 20000 year cycle, by the way, happens because Earth's axial tilt isn't constant. It actually wobbles back and forth. The technical term for this is precession. If you've ever played with a spinning top, you've probably seen this effect happen.

Being a little bigger than a spinning top, this happens more slowly with Earth. As it does, it alters Earth's seasonal variations, gradually causing a change in the Sahara's climate.

Show thread

The name of the Sahara comes from an Arabic phrase, aแนฃ-แนฃaแธฅrฤสผ al-kubrรก (ุงู„ุตุญุฑุงุก ุงู„ูƒุจุฑู‰โ€Ž) meaning "The Greatest Desert". But it was not always a desert.

The climate of North Africa has a slowly varying cycle, and every 20000 years, the Sahara goes from hot desert to wet grassland and back.

5 or 6 millennia ago, the Sahara was green and full of lakes.

Show more
Sunbeam City ๐ŸŒป

Sunbeam City is a Libertarian Socialist solarpunk instance. It is ran democratically by a cooperative of like-minded individuals.