Slightly to the side

Did you know that Earth's tilt affects the school year?

We might refer to Planet Earth as ‘the globe’, but we know it is more like a slightly flattened sphere —experts would say it’s an oblate spheroid— that is also askew. These two details have major consequences for the climate, the night sky, the way we register locations, and even the way schools plan their academic year. How much does the Earth's being at an angle affect us? Let’s find out!

Why is Earth’s axis tilted? The most widely accepted theory is that, millions of years ago, a young planet Earth collided with another celestial body and was left permanently askew. Earth’s axis, supposedly straight before, now has a tilt of 23.5 degrees. It is also believed that the Moon is a product of this collision.

The Earth is permanently tilted, but it’s not static. The degree of the tilt varies slightly across a cycle of thousands of years, which would explain why seasons were harsher or milder across history. But what keeps the Earth from having a more extreme shift? The Moon. All celestial bodies have their own gravity, and they can affect each other. Moon’s gravity has a pull on the equatorial bulge (Earth’s widest part) and prevents it from being affected by other surrounding planets, while also keeping the axial tilt stable.

The different seasons are the first major consequence of the axial tilt. As the Earth orbits around the Sun, it remains tilted in the same direction, which means that, for half of the orbit, one pole is directly facing the Sun, while the other is directly away. For the next half of the orbit, the positions are reversed. The pole closer to the Sun experiences Summer, while the opposite pole goes through Winter (which means that yes, the Southern hemisphere celebrates Christmas during Summer).

When a compass signals North, what is it pointing towards? Spoiler: not the North Pole. The North Pole (also known as True North, or Geographic North) it is a fixed point in the Arctic Ocean intersected by the rotational axis. Maps and coordinates use this point as a reference for the North. A compass, however, points towards the North of the Earth’s magnetic field, which is constantly shifting. The difference between the two Norths is called declination, and is essential for navigation and map reading.

The Earth is a sphere, but most maps are flat. Something is not adding up, and it’s all the fault of a man called Gerardus Mercator, who, in the 16th century, mapped the Earth in a way that represented the meridians and parallels as straight lines. While this was excellent for navigation, it had its negatives: a size distortion. The farthest land masses are from the equator and closest to the poles, the most inflated in size they appear. For example, in the Mercator projection, Greenland appears close in size to the entire African continent, when in reality it is closer in size to the Democratic Republic of Congo.

We all know the difference between the Northern and the Southern hemispheres, but did you know the difference between the Eastern and Western ones? Unlike North and South (which are divided by the equator and experience opposite seasons), the Eastern and Western hemispheres are more of a cultural division, even though they are separated by the Prime meridian and antimeridian. The Eastern Hemisphere is commonly associated with "the Old World" (though it includes Australia), and the Western Hemisphere is "the New World".

Hemispheres split the world equally in size, but not in content. The Northern Hemisphere contains the majority of the Earth’s land mass (around 68%), while the Southern Hemisphere holds the majority of the water (around 80%). As the Northern side has more land, it also houses the majority of the world’s population, around 90%.

North and South experience opposite seasons, but what else is opposite? Storms and whirlpools spin depending on their location—clockwise in the South, counterclockwise in the North—, and the shape of the crescent moon is perceived inverted —a waxing crescent looks like a D from the North and a C from the South.

While bigger celestial objects, such as the Sun or Moon, are visible from any point on Earth, some can only be seen depending on your location. Constellations that are located closer to the Poles are only visible from that hemisphere, and have traditionally been used for navigation and orientation. In the Northern hemisphere, the main examples are Polaris (the north star), Ursa Major (a constellation that contains the Big Dipper), Ursa Minor, Cepheus, and Cassiopeia. For the Southern Hemisphere, the main examples are Crux (the Southern Cross), Centaurus, and Carina.

Most institutions plan their year around Summer, which means that in the Northern Hemisphere, the Academic year usually starts around September and ends in May or June of the following calendar year, while there’s a Winter break in time for Christmas and New Year. In the Southern Hemisphere, the calendar and academic years are matched: the academic year usually begins in March and ends mid-December, right before the Holidays, while Winter break usually falls in July.

10 weird historical events that no one has been able to explain (yet)

Image: Walters Art Museum, Public domain, via Wikimedia Commons

Who doesn't like a good mystery? And if the mystery isn’t a work of fiction but the result of a true story, even better! The great unsolved enigmas of history are absolutely fascinating. Some have been solved over time, but there are still many old secrets for which neither scientists nor historians have found an explanation—yet. Time-travel with us as we uncover 10 of the biggest historical mysteries that will probably never be cracked!

Image: Tanner, Henry S., Public domain, via Wikimedia Commons

Bermeja Island is mentioned in navigation texts written by European travelers and appears in cartography from the 16th to 19th centuries. Old maps place it off the north coast of the Yucatán Peninsula; however, multiple searches over the years have yielded no concrete evidence of its existence.

So, what happened to Isla Bermeja? Was it a cartographic error? Did it sink due to a tidal wave? Because of its geopolitical significance, some have even suggested that it was blown up by the CIA! A 2009 study by the Autonomous University of Mexico concluded that Isla Bermeja does not exist today, nor were any traces found at its supposed coordinates. Yet, it will forever remain a mystery that will surely keep many entertained.

Image: Credit: Big Ear Radio Observatory and North American AstroPhysical Observatory (NAAPO)., Public domain, via Wikimedia Commons

In 1977, Ohio State University’s Big Ear radio telescope, used in the search for extraterrestrial intelligence, detected a signal now known as the Wow! signal. While reviewing the data, astronomer Jerry R. Ehman noticed a sequence represented as "6EQUJ5." Baffled by the anomaly, he circled it and wrote "Wow!" in the margins.

The signal lasted 72 seconds and, unfortunately, has never been repeated. To this day, no one can fully explain the phenomenon, although some suggest it may have come from a man-made source. Still, the Wow! signal remains one of the strongest candidates for potential extraterrestrial contact ever detected.

Image: Edward S. Curtis, Public domain, via Wikimedia Commons

How is it possible for an entire village to vanish without a trace? Believe it or not, this is said to have happened nearly a century ago. According to lore, a small Inuit village in Canada was well known among fur trappers who visited regularly to trade. But in 1930, something very strange supposedly occurred.

A hunter named Joe Labelle claimed he visited the village one day and couldn’t find a single person. Reports said there were guns and food left behind, and even claims that the graves in the cemetery were empty. A thorough investigation, however, found no conclusive evidence of what happened to the villagers. Some witnesses from nearby towns even reported seeing a huge green light. Theories ranged from mass migration to extraterrestrial abductions. The Royal Canadian Mounted Police has since dismissed the case as an urban legend. Some still believe the story to be true.

Image: bbb

We know thousands of shipwreck stories, but this one is quite unique. The MV Joyita, designed to be nearly unsinkable, was found adrift in the South Pacific, practically unharmed, but the crew had disappeared completely.

In October 1955, the American merchant vessel left the port of Apia in Samoa with 16 crew members and 9 passengers bound for the Tokelau Islands. After days without news, a rescue mission was launched. Five weeks later, the Joyita was spotted more than 600 miles west of its intended route. The vessel was partially submerged, and there was no sign of the passengers or crew. Four tons of cargo and all three life rafts were missing. They were never seen again.

Image: Gary Todd from Xinzheng, China, CC0, via Wikimedia Commons

Do you know where one of the best-preserved mummies was found? Hint: not in Egypt. Xin Zhui, the Marquise of Dai during the Western Han Dynasty in China, was discovered in her tomb at Mawangdui 2,000 years after her death, along with hundreds of valuable documents and artifacts.

What makes this mummy so extraordinary is how well-preserved her body is. Her organs and veins remain intact, and she still has hair and even eyelashes. Scientists analyzed the fluid present in the coffin and discovered it was acidic and contained salt and magnesium. They believe this mysterious liquid may have been responsible for preserving Xin Zhui so well. What they don’t know is whether it was intentionally poured into the coffin or came from the body itself.

Image: Yoichi Okamoto, Public domain, via Wikimedia Commons

The United States has its fair share of presidents who died while in office, but none of our 45 presidents have ever disappeared without a trace. Did you know that this actually happened in The Land Down Under?

Harold Edward Holt was the Prime Minister of Australia from 1966 until his presumed death in 1967. He loved the ocean and spearfishing. During a weekend trip with friends, Holt visited the remote Cheviot Beach to take a swim. Rough sea conditions that day caused him to be swept away by the waves, and he never reappeared. Despite an intensive search, his body was never found, which has given rise to numerous conspiracy theories. Ironically, Australians built the Harold Holt Memorial Swimming Centre in Melbourne in his honor.

Image: FBI, Public domain, via Wikimedia Commons

Many famous criminals have managed to remain unidentified for decades, but the D.B. Cooper case is something else entirely. In 1971, Cooper boarded a flight from Portland to Seattle. Shortly after takeoff, he showed a flight attendant a device he claimed was a bomb and demanded four parachutes and $200,000 in cash.

The crew landed to meet Cooper’s demands in exchange for the passengers and then took off again. As the plane flew over southwestern Washington, Cooper jumped into the cold, rainy night carrying his haul. His whereabouts and true identity were never discovered, although it is likely he didn’t survive the jump. In 1980, some of the ransom money was found near the Columbia River. Although the FBI officially closed the case in 2016, amateur sleuths continue to try to crack it.

Image: Pieter Brueghel the Elder, Public domain, via Wikimedia Commons

Can you imagine an epidemic where the main symptom is uncontrollable dancing? Sounds like science fiction, doesn’t it? Yet this really happened during the Middle Ages. In 1518, a dancing plague struck Strasbourg, Alsace, in what is now France. This strange condition affected up to 400 people, making them dance frantically for weeks. It is said that some even died of heart attacks, exhaustion, or strokes.

Doctors and authorities tried all kinds of measures to stop the spread. They even banned music for a while! To this day, scientists are not certain what caused this bizarre condition: it may have been food poisoning from toxins in the ergot fungus, or perhaps a case of stress-induced mass hysteria.

Image: Public domain, via Wikimedia Commons

The Voynich manuscript is a codex written roughly 500 years ago in an unknown language and writing system by an anonymous author. Known as Voynichese, the manuscript was named after Wilfrid Voynich, a Polish bibliophile and antiquarian who purchased it in 1912.

Radiocarbon testing has shown that it dates to the early 15th century. Many cryptographers and codebreakers have attempted to decipher its roughly 240 pages without success. The manuscript contains diagrams and illustrations of unknown plants and astrological symbols. Some believe it may be a made-up language, a secret code, a work of fiction, or even a hoax. If you think you can solve this mystery, the Voynich manuscript is available for viewing at Yale University’s Beinecke Rare Book and Manuscript Library.

Image: Bernhard

Similar to the Voynich manuscript, the Phaistos Disc is a fired clay disc believed to have been created during the Bronze Age. It was discovered by an Italian archaeologist in the basement of a palace in Crete, Greece, in 1908.

What makes this disc fascinating is that it contains a mysterious message. Stamped into the clay is a set of signs, forming a text that many scientists have tried to decipher—without success. It is considered an early attempt at printing, a technological innovation that would not become widespread for several centuries. While enthusiasts still hope the enigma can be solved, this is unlikely unless other documents are discovered to provide context.