Fogbow

Tiredretiredlawyer wrote: ↑Sun Jul 17, 2022 9:44 am I can see a pregnant teenage girl telling her parents, "I don't know HOW I got pregnant. It must be parthenogenesis."

Tiredretiredlawyer wrote: ↑Sun Jul 17, 2022 9:44 am I can see a pregnant teenage girl telling her parents, "I don't know HOW I got pregnant. It must be parthenogenesis."

Earth Is Suddenly Spinning Faster. Why Our Planet Just Recorded Its Shortest Day Since Records Began

Until a few years ago it had been thought that Earth’s rotation was slowing down after several successive measurements by atomic clocks since 1973.

The International Earth Rotation and Reference Systems Service (IERS) had even begun adding leap seconds every now and again to make up for the slower spin (it last happened on December 31, 2016).

Over a longer time period that may still be the case—Earth’s rotation may, in general, still be slowing down.

After all, the Moon is gradually slowing down the Earth’s rotation. Its gravitational pull causes tides and makes the Earth’s orbital path around the Sun slightly elliptical.

How fast is Earth rotating?

However, in the last few years the atomic clocks have shown that Earth rotation is now speeding up. In fact, we could be beginning a 50 year period of shorter days.

In 2020 scientists recorded the 28 shortest days since 1960. Last year that trend did not continue, with the shortest day in 2021 being longer than in the previous year.

However, on June 29, 2022 our planet completed its quickest-ever spin, followed quickly by a day that lasted 1.50 milliseconds less on July 26, 2022.

The previous record for the shortest rotation was July 19, 2020, when the Earth’s rotation took 1.4602 milliseconds less than 24 hours.

Why is Earth speeding up?

The cause of the differing speed of Earth’s spin is unknown, but theories abound:

The melting of the glaciers means less weight on the poles
Motions of our planet’s inner molten core
Seismic activity
The “Chandler wobble”—the movement of Earth’s geographical poles across its surface

Why Earth’s rotational speed is important

Earth’s quickening rotation has consequences because atomic clocks—which are used in GPS satellites—don’t take into account the Earth’s changing rotation.

If Earth spins faster then it gets to the same position a little earlier. A half-a-millisecond equates to 10-inches or 26 centimetres at the equator. In short, GPS satellites—which already have to be corrected for the effect of Einstein’s general relativity theory (the curve of space and time)—are quickly going to become useless.

There are also potentially confusing consequences for smartphones, computers and communications systems, which synchronize with Network Time Protocol (NTP) servers. It’s defined as the number of seconds since 00:00:00 UTC on January 1, 1970.

To solve all this international timekeepers may need to add a negative leap second— a “drop second.” Though Earth may already be spinning as quickly as it ever will, with a slowdown inevitable.

Only time will tell.

Humans Exhibit Air-Cleansing Aura Around Their Bodies: Study

A new study has found that humans exhibit an aura that can be visualized but is more scientific in nature than spiritual.

This aura, invisible to the naked eye, is present around human bodies and could be cleaning the air we breathe. The study, published in the journal Science, has found that a haze of air-cleansing molecules is formed by the human body when ozone in the air comes in contact with the oil in our skin.

The air-cleansing molecules are nothing but transient OH radicals. The OH radicals have previously been known for neutralizing toxic molecules in the presence of sunlight that produced it. This has earned them the moniker "detergents of the atmosphere."

The new study confirms the presence of OH radicals, which are being made by our human bodies. This is a first in the scientific field. However, experts are not sure whether the aura, technically called the oxidation field, is good or bad because of a lack of studies on the subject.

The presence of an aura around the human body is an ancient idea. There is a lot of talk about it in spiritual circles. This aura is in stark contrast to the one discovered by the scientists and is not to be confused with the one talked about in the study.

A Man Switched A Helicopter Engine Off Mid-Flight To Prove A Point

If a plane’s engine fails, you’d think (or like to think) its aerodynamic properties could glide you down to safety. Helicopters, on the other hand, are pretty clunky-looking things. So if you turned off the engine mid-flight, you’d probably expect the results to be pretty messy.

Neil deGrasse Tyson posted a tweet last year saying something along those lines, “FYI: An airplane whose engine fails is a glider. A helicopter whose engine fails is a brick.” Knowing a thing or two about helicopters, Destin Sandlin from the SmarterEveryDay YouTube channel decided to enlist the help of some experienced helicopter pilots to prove deGrasse Tyson wrong.

After enjoying a cruise around the stunning lakes of British Columbia, they go on to demonstrate how to safely land a helicopter when its motor has failed using a technique called “autorotation.” Using this technique, Gerry Friesen – a helicopter pilot with a whopping 16,000 flight hours under his belt – even believes landing a failed helicopter is safer than landing an airplane with a busted engine.

Of course, deGrasse Tyson does have a point. If the propellers stop working, the helicopter would drop like a brick. However, if the propellers are still moving, then it’s possible to land safely.

As Destin explains in the video: "If the rotor blade quits turning you are going to fall like a brick – but helicopter pilots have a physics trick to keep that from happening." All it requires is a simple lever and a hell of a lot of practice. Check it out for yourself in the video below.

Autorotation

This article is about autorotation of rotary wing aircraft. For autorotation of fixed-wing aircraft, see Autorotation (fixed-wing aircraft).

Airflow through a helicopter rotor. Above, the rotor is powered and pushing air downward, generating lift and thrust. Below, the helicopter rotor has lost power, and the craft is making an emergency landing,

Autorotation is a state of flight in which the main rotor system of a helicopter or other rotary-wing aircraft turns by the action of air moving up through the rotor, as with an autogyro, rather than engine power driving the rotor.[1][2][3] The term autorotation dates to a period of early helicopter development between 1915 and 1920, and refers to the rotors turning without the engine.[4] It is analogous to the gliding flight of a fixed-wing aircraft. Autorotation has also evolved to be used by certain trees as a means of disseminating their seeds further.

The most common use of autorotation in helicopters is to safely land the aircraft in the event of an engine failure or tail-rotor failure. It is a common emergency procedure taught to helicopter pilots as part of their training.

In normal powered helicopter flight, air is drawn into the main rotor system from above and exhausted downward, but during autorotation, air moves up into the rotor system from below as the helicopter descends. Autorotation is permitted mechanically because of both a freewheeling unit, which allows the main rotor to continue turning even if the engine is not running, as well as aerodynamic forces of relative wind maintaining rotor speed. It is the means by which a helicopter can land safely in the event of complete engine failure. Consequently, all single-engine helicopters must demonstrate this capability to obtain a type certificate.[5]

The longest autorotation in history was performed by Jean Boulet in 1972 when he reached a record altitude of 12,440 m (40,814 ft) in an Aérospatiale SA 315B Lama. Because of a −63 °C (−81.4 °F) temperature at that altitude, as soon as he reduced power, the engine flamed out and could not be restarted. By using autorotation he was able to land the aircraft safely.[6]



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

Ok so, as part of NASA’s SLS-1 Mission in 1991, over 2,000 moon jellyfish were launched into space on the space shuttle Columbia. The purpose of the science experiment was to study how the lack of gravity in space effects jellyfish development. They wanted to know whether adult jellyfish would behave differently once back in the gravity of Earth. This was because humans and jellyfish both share a common orientation according to gravity. Anyway, in the early 90s there were close to 60,000 jellyfish orbiting Earth. I’m not sure what to do with this info, but here it is:

Scientists Destroy Illusion That Coin Toss Flips Are 50–50
Researchers go to great lengths to prove a tiny bias in coin flipping

BY SHI EN KIM
JANUARY 1, 2024
January 2024 Issue - Statistics

The phrase “coin toss” is a classic synonym for randomness. But since at least the 18th century, mathematicians have suspected that even fair coins tend to land on one side slightly more often than the other. Proving this tiny bias, however, would require hundreds of thousands of meticulously recorded coin flips, making laboratory tests a logistical nightmare.

František Bartoš, currently a Ph.D. candidate studying the research methods of psychology at the University of Amsterdam, became intrigued by this challenge four years ago. He couldn't round up enough volunteers to investigate it at first. “Nobody was stupid enough to spend a couple of weekends flipping coins,” he says. But after he began his Ph.D. studies, he tried again, recruiting 47 volunteers (many of them friends and fellow students) from six countries. Multiple weekends of coin flipping later, including one 12-hour marathon session, the team had performed 350,757 tosses, shattering the previous record of 40,000.

The flipped coins, according to findings in a preprint study posted on arXiv.org, landed with the same side facing upward as before the toss 50.8 percent of the time. The large number of throws allows statisticians to conclude that the nearly 1 percent bias isn't a fluke. “We can be quite sure there is a bias in coin flips after this data set,” Bartoš says.

The leading theory explaining the subtle advantage comes from a 2007 physics study by Stanford University statistician Persi Diaconis and his colleagues, whose calculations predicted a same-side bias of 51 percent. From the moment a coin is launched into the air, its entire trajectory—including whether it lands on heads or tails—can be calculated by the laws of mechanics. The researchers determined that airborne coins don't turn around their symmetrical axis; instead they tend to wobble off-center, which causes them to spend a little more time aloft with their initial “up” side on top.

For day-to-day decisions, coin tosses are as good as random because a 1 percent bias isn't perceptible with just a few coin flips, says statistician Amelia McNamara of the University of St. Thomas in Minnesota, who wasn't involved in the new research. Still, the study's conclusions should dispel any lingering doubt regarding the coin flip's slender bias. “This is great empirical evidence backing that up,” she says.

It isn't difficult to prevent this bias from influencing your coin-toss matches; simply concealing the coin's starting position before flipping it should do the trick. Alternatively, you can do away with flipping altogether by jiggling a coin between your curved palms. But if your friends are unaware of the tiny bias, you may as well benefit from your slight advantage. After all, 51 percent odds beat a casino's house advantage for six-deck blackjack. “If you asked me to bet on a coin,” Bartoš says, “why wouldn't I give myself a 1 percent bias?”



https://www.scientificamerican.com/arti ... are-50-50/