Earth’s day was half hour shorter 70 million years ago
Using data from an ancient fossil shell, scientists have determined that 70 million years ago the Earth’s day was about 30 minutes shorter, and that a year comprised 372 days.
This result is not a surprise, as scientists have known for a long time that the day has been growing longer as the Moon’s gravity, producing tides, wears away at the Earth’s rotation. This data however is the most precise yet, and will allow scientists to better constrain not only the Earth’s changing rotation over time but the Moon’s orbit. As it slows the Earth’s rotation its own orbit around the Earth gets longer, pushing it farther away.
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Using data from an ancient fossil shell, scientists have determined that 70 million years ago the Earth’s day was about 30 minutes shorter, and that a year comprised 372 days.
This result is not a surprise, as scientists have known for a long time that the day has been growing longer as the Moon’s gravity, producing tides, wears away at the Earth’s rotation. This data however is the most precise yet, and will allow scientists to better constrain not only the Earth’s changing rotation over time but the Moon’s orbit. As it slows the Earth’s rotation its own orbit around the Earth gets longer, pushing it farther away.
Readers!
Please consider supporting my work here at Behind the Black. Your support allows me the freedom and ability to analyze objectively the ongoing renaissance in space, as well as the cultural changes -- for good or ill -- that are happening across America. Fourteen years ago I wrote that SLS and Orion were a bad ideas, a waste of money, would be years behind schedule, and better replaced by commercial private enterprise. Only now does it appear that Washington might finally recognize this reality.
In 2020 when the world panicked over COVID I wrote that the panic was unnecessary, that the virus was apparently simply a variation of the flu, that masks were not simply pointless but if worn incorrectly were a health threat, that the lockdowns were a disaster and did nothing to stop the spread of COVID. Only in the past year have some of our so-called experts in the health field have begun to recognize these facts.
Your help allows me to do this kind of intelligent analysis. I take no advertising or sponsors, so my reporting isn't influenced by donations by established space or drug companies. Instead, I rely entirely on donations and subscriptions from my readers, which gives me the freedom to write what I think, unencumbered by outside influences.
You can support me either by giving a one-time contribution or a regular subscription. There are four ways of doing so:
1. Zelle: This is the only internet method that charges no fees. All you have to do is use the Zelle link at your internet bank and give my name and email address (zimmerman at nasw dot org). What you donate is what I get.
2. Patreon: Go to my website there and pick one of five monthly subscription amounts, or by making a one-time donation.
3. A Paypal Donation or subscription:
4. Donate by check, payable to Robert Zimmerman and mailed to
Behind The Black
c/o Robert Zimmerman
P.O.Box 1262
Cortaro, AZ 85652
You can also support me by buying one of my books, as noted in the boxes interspersed throughout the webpage or shown in the menu above.
A friend of mine, who studied under van Allen, once told me the tale of one of his exam questions. He was supposed to calculate the rate at which the Earth’s rotation is slowing. (Or was it the rate at which the Moon is getting farther from the Earth? Well, the rest of the story is more memorable, to me.) He chose to use conservation of energy between the Earth’s rotation and the Moon’s orbit.
The proper method turned out to be conservation of angular momentum. The problem was that the tides take up some energy as well as the magma, which is heated as the Earth is warped by the tidal action, so energy is not conserved with the changes in the two motions. Tidal heating is why there are volcanoes on Io.
The “war stories” that we get from scientists are a bit different than those from soldiers.
“Why did the chicken cross the Mobius Strip?”
(Big Bang Theory
https://youtu.be/j9u42WSaF04
0:07
So, that is why my nap times seem to be getting longer.
whew. I was worried that it was me.