I had a friend sometime ago, when I was still in the University. Very funny and amazing guy. He was always finding it difficult to read his books and do his assignments. Very social guy, he loved to party and groove. I remember his constant complains, he would always say, how he wished he had more than 24 hours a day.
He would go on exaggerating that, if only he had more than 24 hours a day, he would have been the most intelligent student in the whole school, because he would have had more time to read after spending the major part of his day playing around. He would continue saying that he would have made so much money for himself, that he would have been a wealthy man already and so on. Trust me guys, I would make sure that he reads this article, so that he realizes that he was lucky to be having the 24 hours a day, that he was throwing away back then in school.
A long time ago, 1.4 billion years ago to be precise, the Earth was having only 18 hours a day. That is 6 hours short of the 24 hours we enjoy today. I can only imagine waking up in the morning, and having only 18 hours a day, to do all the many things that I need to get done; that's not going to be funny at all, and might really prove difficult to manage.
We should all be thanking the moon; because it's the moon that has made it possible for us to be enjoying the 24 hours a day we are enjoying and unfortunately, some of us are not appreciating it. So next time, when someone is complaining and making all those funny statements, that they wish that they had more than 24 hours a day, smile!, and threaten them that if they keep on repeating that statement, you would take them back in time 1.4 billion years ago, and that they would wish and even beg to return back to 2018!! (smiles!).
I'm going to be discussing with us the reason for this difference in length of day. So guys, just relax and let's roll together!
Source: Pixabay. Author: deMysticWay. ( CCO ) Licensed
For better understanding, we would be talking briefly about the Earth and the Moon
Wikimedia Commons: Earth from space. Author: NASA/GSFC/Reto Stöckli, Nazmi El Saleous, and Marit Jentoft-Nilsen. (Public domain) Licensed
Planet Earth is the 3rd planet in the universe to the sun. And the only planet that is known to harbor life. Radiometric dating has it that the Earth was formed there about 4.5 billion years ago. The gravitational field of the Earth interacts with the other objects and planets in space, especially the moon and the sun. The moon is known to be the only natural satellite of the Earth. Planet Earth revolves around (goes around) the sun in about 365.26 days, which is a period of time known as a year. As the Earth revolves around the sun, it also rotates about its axis there about 366.26 times.
Ocean tides occur as a result of the gravitational effects of the moon and the Earth; this helps in stabilizing the Earth's orientation on its axis. The interior of the Earth is active, containing solid iron core, as well as a liquid outer core that produces the magnetic field of the Earth.
It has been speculated that life thrives on Earth because of the distance of the Earth from the sun, geological history and the physical properties of the Earth. 23 hours and 56 minutes is the length of a solar day on planet Earth, approximately 24 hours a day. The axial rotation of Earth is counterclock-wise. A complete rotation of the Earth about its axis makes a day.
Wikimedia Commons: Moon nearside. Author: NASA/GSFC/Arizona State University. (Public domain) Licensed
The moon is a body that orbits Earth. It is the only natural satellite of Earth. It is known to be a large natural satellite in the universe, precisely the 5th largest in the solar system. The moon is found after lo, Jupiter's satellite; which is the second densest in the solar system in relation to those satellites whose densities are already known.
The moon is said to have been formed about the same time as Earth, there about 4.5 billion years ago. The moons rotation synchronizes with that of the Earth, as a result, it shows the same side to planet Earth, which is called its near side. The Earth's sky has the sun as the brightest regularly visible object, and the moon as the second-brightest. The surface of the moon is actually dark, but when related to the night sky it appears bright. The gravitational influence of the moon produces the body tides, the little lengthening of day and the ocean tides.
The moon appears in the sky as almost the same size as the sun; this is because the sun is 400 times farther than the moon and 400 times larger. This is why the moon covers the sun almost precisely when solar eclipse is experienced. In the far future, this apparently equal visual size of the Moon and Sun will not continue, and this is because the distance of the moon from the Earth is gradually increasing.
This brief discussion about the moon would not be complete without me telling you guys when the Moon was first reached. That was in 1959 by a spacecraft without people (unmaned spacecraft), meaning no man was in the spacecraft. This unmanned spacecraft was of the Soviet Union's Luna Program. It's only the United States Nasa Apolla Program that has achieved manned lunar missions till date.
The very first manned mission was in 1968 by Apollo 8, and afterwards there was a six manned mission between the period of 1969 and 1972. Lunar rocks have been returned to Earth from these missions in order to have a geological understanding of the Moon, its origin, history, and its internal structure.
The reason why 1.4 billion years ago, a day on Earth was about 18 hours
A recent research has been able to show a very deep history of the relationship between our planet Earth and the Moon. The research was able to explain this relationship 1.4 billion years ago. It showed that a day lasted about 18 hours, 1.4 billion years ago. This was due to the fact that the moon was closer to planet Earth and affected the way Earth rotated around its axis.
The research was able to explain that just the same way a spinning figure skater would slow down as he/she stretches out their arms, the Earth also slows down as the moon moves away.
The study made use of a statistical method, a tool, that connected geological observation with astronomical theory, in what is called astrochronology. This method was used to study planet Earth's geological past, reeorganize the history of the solar system and comprehend climate changes from millions and billions of years ago captured in rock record.
The research was aimed at using astrochronology to understand time in distant past, and to produce geological ancient time scales. Their ambition was also to be able to study rocks from billions of years ago in such a way that is similar to how we study geologic processes in modern time.
Flickr: 2017 Eclipse- Earth, Moon, Sun. Author: NASA Goddard Space Flight Center. (CC BY 2.0) Licensed
The movement of Earth in space is very well influenced by other celestial/ spatial bodies that exert force on it; such as the moon and other planets. All these put together, determines the variations of the Earth's rotation around its axis and in Earth's orbit around the sun. The variations caused by the influence of other spatial bodies on Earth are collectively called Milankovitch cycles. The Milankovitch cycles determine the distribution of sunlight on Earth, which means that the Milankovitch cycles determine the rhythms of Earth's climate. Stephen Meyers, Professor of geoscience, studied this climate rhythm in the rock record, from millions of years ago.
But he couldn't study rock records from billions of years, because radioisotope, which is a typical geologic means, do not give precise information that are needed to understand the cycles. It was also difficult because of lack of knowledge of the moon's history and by what is called solar system chaos.
There are many moving parts in the solar system, which includes other planets revolving around the sun. Slight variations in the parts moving can lead to very big changes or affects millions of years later, this is called solar system chaos, and attempting to understand it is extremely difficult. In 2017, last year, Meyers and colleagues broke the code on the chaotic solar system in a research on sediments from a rock formation 90 million years old, that captured the climate cycles of Earth. Meyers and his colleagues tried to study older rocks but got less reliable conclusions.
Currently, the moon is moving away from Earth by 3.82cm every year. As a result of the fact that Meyers was not coming to reliable conclusions, he teamed up with a Lamont research Professor at Columbia, called Alberto Malinverno. Both teams worked together using a statistical method developed in 2015 by Meyers to handle uncertainty in the study system. This method was called TimeOpt- with geological data, astronomical theory and high level statistical approach, which they called Bayesian inversion. This helped the researchers to get a better control on the uncertainty of the system.
The approach was then tested, it was called TimeOptMCMC; on two rocks- the Xiamaling formation of 1.4 billion years old from Northern China and a rock from Southern Atlantic Ocean, a 55 million-year-old record.
Using this approach, they were able to assess reliably, layers of the rock. They were able to understand the geologic variations in the record in the direction of the rotation of the planet Earth and the shape of Earth's orbit, both in deep time and in more recent time, as well as handle uncertainty. Hence, they were able to determine the distance between the moon and the Earth, and determine as well the length of day.
The research has it that the reason for the 24 hours a day that we are enjoying is that the moon is moving away from the Earth every year by 3.82cm. And the more the moon moves away, the slower the Earth rotates around its axis. Therefore, if we take it back, 1.4 billion years ago, the moon was closer to the Earth and as a result, the Earth was rotating faster. Hence, at the time, it took the Earth 18 hours to make one complete rotation around its axis. And that's why we had 18 hours a day 1.4 billion years ago.
Honestly, I'm personally happy to be in 2018! and enjoying the 24 hours a day that I have, what about you?
Thanks for reading!
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