Ever feel bad that you don't know everything there is to know in the world? That's okay. No one, not even people at the tops of their fields, know everything. There are things all across the globe--and beyond--that continue to befuddle scientists and researchers. Here are 23 of them:
1. The Sun's corona
The corona is made of plasma, but for some reason, it's hotter than the surface of the sun itself. The sun's surface is about 5,800 degrees Kelvin, but the corona can reach 1 to 3 million degrees Kelvin. That's really hot.
2. Animal migration
All kinds of animals migrate, but somehow, they all know how to do it and where to go, even if they're separated from others of their species. How the knowledge got hardwired in there is still a mystery.
3. The Hum
Several places are known to have "the hum," which is a low-frequency humming or droning sound whose source remains unclear. Taos, NM, is best known for its hum, but only 2% of the population has the ability of hearing it. Those 2% find it super irritating.
4. Jellyfish Lake
The "jellyfish lake" is connected to the ocean via underground channels, and it got its name from the jellyfish that migrate in and out daily. (How, if they barely have brains? See above.) But between 1998 and 2000, there was evidently some kind of jellyfish boycott, because they just didn't for those two years.
5. Ice circles
Ice circles occur in slow moving water in freezing temperatures. It's thought they're formed in eddy currents, but there's no proof. They can get up to 15 meters in diameter.
Bigfoot and the Yeti have been favorites of paranormal fans for years, and the jury's still out on if they're supposed to be the same species. Most scientists, and most people, dismiss them as myth, but some believe they may be members of a relic population of ancient giant apes.
7. Saturn's storm
A NASA spacecraft spotted this hurricane on Saturn in 2013. Its eye measured 2,000 km across. On Earth, hurricanes are caused by warm ocean currents, but it's unknown how this storm started on Saturn.
8. Fish from heaven
There have been many cases of weird stuff falling from the sky. In 2000 in Ethiopia, it rained thousands of fish. It's thought they were lifted and transported by a storm, but the weird thing is that when animals fall from the sky, it only ever seems to be one species at a time.
9. Naga fireballs
The Naga fireballs are a supposed phenomenon occurring in Thailand and Laos, where glowing red orbs are said to rise from Mekong River. No one knows how they might form, if they form at all.
10. The Silent Zone
The Mapimi Silent Zone outside of Durango, Mexico, is known for its utter silence and for its seeming ability to attract objects from the sky, including Apollo boosters, a test missile, and a huge meteorite. Coincidence?
11. Disaster flashes
Before an earthquake strikes or a volcano erupts, some people report seeing flashes of light, and have for centuries. In the 1960s, the phenomenon was photographed for the first time, but there's still no explanation as to why it happens, or if both natural events have the same reasons behind their flashes.
12. The Moon illusion
The moon always seems huge when its on the horizon, getting smaller as it climbs higher into the sky. But studies show that from the same vantage point, the moon measures the same when compared to another object regardless of its position relative to the horizon. It just looks big without being big.
13. Synchronized bugs
A species of firefly living in the Great Smoky Mountains National Park is the only one that can synchronize their blinking, and they do it for a little while each year. Why and how? No one knows.
That cats purr is well known, and most people associate it with a cat being happy. In fact, though, it's not clear why they purr. They purr when you pet them, but also while eating and sometimes while giving birth. So its actual meaning is unknown.
15. Singing whales
Male humpback whales' songs were once thought to be part of attracting mates, but it seems they just like to sing. The songs are unique, and whales can learn them from other whales and in turn teach the songs to their own whale friends elsewhere. Hooray for musical whales!
16. Before the Big Bang
The Big Bang theory says that the universe was formed 14 billion years ago from one point where all matter was contained (including you!) and that the matter is still expanding outwards. But as for what the universe was like before that? We don't know.
17. The Bermuda Triangle
The Bermuda Triangle is another place that's mystified people for years. Aircraft and ships have mysteriously disappeared here, although it's not necessarily more prone to disappearances than anywhere else on the planet. Numerous theories abound, from methane bubbles to UFOs.
Like Bigfoot, the Loch Ness Monster, affectionately known as Nessie, is another favorite cryptid. Numerous photos have been offered up as "proof," but most have been proven to be fakes. Still, Nessie sightings continue to be reported.
19. The fairy rings
The grassy land of southern Africa is pockmarked with circular areas of barren land, whose diameters vary from 2 to 15 meters. When and how they were formed is a mystery.
20. Sailing stones
Sailing stones are rocks that seem to move on their own, leaving long trails in smooth valley floors. They are not been moved by humans or animals, and can even turn over and change direction. Scientists suspect they might be pushed by wind on a thin, slippery layer of clay, but it's not been proven.
21. Suicide whales
Up to 2,000 whales beach themselves each year, and it looks like they might do it on purpose. Why whales would commit suicide (most beached whales die by being crushed under their own weight) is a mystery, but they've been at it for thousands of years.
22. Ball lightning
Ball lightning is described as a spherical or oblong, well, ball of electricity seen during a thunderstorm, and lasting longer than normal lightning. It's been reported for centuries, but there's still no explanation of how it forms.
23. Floating lights
In a valley in Norway, strange lights have been shining since the 1940s.They float bove the ground and during the 1980s, the lights were seen up to 20 times a week. Since then, they've diminished, and are only seen about 20 times a year. No one knows what they are or where they come from.
So there you have it. The universe is a mysterious place, with ever more things to discover and unravel. Maybe in the future, we'll have the answers to these bizarre mysteries, but until then, we'll enjoy being puzzled!