Smallpox: the only human disease that has been successfully eradicated.
This is a unique disease because it’s one of the deadliest known to humanity and the only one that was completely eradicated. Smallpox has no cure or treatment and the smallpox vaccine was the first successful vaccine to ever be invented. It was discovered that peasants who worked with cattle contracted a much more benign version of the disease and thanks to that, they were immunized against it. This showed that administering the attenuated virus could generate antibodies to any strain of the same virus. Later, this would become the vaccine we know today.
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First 4 year s ago
#4 interesting. but why those "mystery" facts alongside it? of course tree grow there after more than 100 years. But it's a swamp area, so no, the trees don't grow on every inch.
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Limited 4 year s ago
#6 i dond get it. Uranus does not have an internal heat source but have a boiling ocean? How does it boil then? Can someone explain pls i am stupid for this 
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Limited 4 year s ago
#6 The caption is poorly written. It meant to say that Uranus does not give off more heat than it receives from the Sun, unlike the other planets. It's core is actually about 9000 degrees Fahrenheit. The oceans are a water-ammonia mix that is usually near frozen because of the intense coldness of the planet, but does occasionally boil off. Boiling liquid does not necessarily mean hot liquid. For example, water boils on Mt Everest at only 160 degrees instead of the normal 212 degrees at sea level. If you put cold water in a vacuum chamber it boils violently. It's our atmospheric pressure here on earth that keeps water in the liquid state.
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Kitten 4 year s ago
The Mississippi river did in fact run backwards once before. During an 1812 earthquake that was centered on the New Madrid fault line.
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Driving 4 year s ago
#3
Explained almost 3 years ago:
https://earthsky.org/space/wow-signal-explained-comets-antonio-paris
Explained almost 3 years ago:
https://earthsky.org/space/wow-signal-explained-comets-antonio-paris
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Close 4 year s ago
Kitten is right (I live in Missouri near the New Madrid fault line). It was taught to us in grade school.
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Delight 4 year s ago
Low atmospheric pressure is also why Mars has no liquid water on its surface, and it is the reason that water ice on Mars sublimes.
Explained almost 3 years ago:
https://earthsky.org/space/wow-signal-explained-comets-antonio-paris