Earth Definition and 1000 Threads

It's well known that the tidal effect of the Moon on the Earth causes the Earth's rotation to slow down and the radius of the Moon's orbit to increase over time. However, the Sun also exerts a tidal effect on the Earth, which should also contribute to slowing down the Earth's spin. This raises...

It is being reported in the press that there is new evidence for pebble accretion models https://www.bbc.co.uk/news/science-environment-51295365 Normally when we think of the very early Earth we think of being formed violently . This model seems more gentle. I am wondering what that means for...

I've been watching an interesting nature program on Netflix called Night On Earth. The film was all taken at night using low light and infrared cameras. I was surprised how many animals and insects see well at night. It makes me curious. Do we know how much of the infrared spectrum...

Here are 2 questions that I have tried to answer and was hoping if these are right ways to go about it? Q1) Find the distance in meters (m) between centre of the Moon and the centre of the Earth, assuming that the Moon moves in a circular orbit with a period of 27.5 days. Take the mass of the...

In the USA if you go to Mexico your money is worth a lot more over there. Likewise if you are a scifi alien with a scifi starship your money should go much farther in the USA than it would on your homeworld.The question is... how far? How much would a human nation realistically let alien money...

Objects fall on Earth at 9.8 m/sec² independent of mass. If gravity is independent of mass why does Jupiter pull an object more than the Earth does? Is that inconsistency within the law or in my perception?

Oldest material found on earth? This popped up in live science https://www.livescience.com/oldest-material-on-earth.html This on PNAS https://www.pnas.org/content/early/2020/01/07/1904573117 Any discussions here? Nothing on Murchison.

What would be the mass be of a planet traveling at 500,000 mph - if we assume the planet has the same mass as the Earth i.e. 5.9 sextillion tonnes?

I had the wonder of whether, due to the speed difference, clocks ran at a different speed on the equator than on the poles. I then researched this, and found that, due to being closer to the centre of the Earth at the poles due to the bulging of the Earth due to spinning, the two essentially...

Hi! This is a problem from my physics 1 high school course. I've tried using the first and third equations to determine period (answer of 8326.9544s.), however that was incorrect and I never even touched G. I'm not sure where to go from here at all. Any help is appreciated!

hi guys, I have a rock, I think its a complete star or maybe core meteorite, what do you think about it? It was found a few months ago in mountains in Shandong Province in China. desc: composition：Nickel iron diameter: 4cm weight:264g Regards Leonard

If there was no atmosphere and a point mass was released at the 45th parallel and able to counteract the centripetal force of gravity (hovering 10ft off the surface), how long would it take before it ended up at the equator.

Summary: What if the Earth rotated about its axis in a N-S direction instead of doing so in an E-W direction. Hi, Just curious: What would be the effects/consequences if the Earth rotated about its axis in a North-South ( or South-North) direction instead of an East-West one as it currently...

Hello, I know it suppose to be a relatively basic question but still somehow I can't fully understand it. Let assume that a man jumps vertically on the equator, while the Earth is of course rotating. What will happen to the value of his linear momentum in the horizontal axis? It seems to me...

If the sun has a gravitational influence on Earth and on its moon then why isn't the moon revolving around the sun. If the gravitational force of sun is large enough to make planets like Jupiter revolve around it (which has a greater mass than that of the moon.) Why not moon?

I came across an article regarding a study that claimed ice ages correspond with extreme changes in the tilt of the Earth. I'm curious what others think about this. Is this just another unqualified scientific study put out there to confuse the climate change debate? Is the science behind it...

First, i think this is the correct place to ask this question. So the story is that I'm working on a piece of fiction that I want to be as accurate as possible. One part of it involves an object that travels from Mars to earth. This would have been between February 22, 1901 (beginning of...

This question required measurements which are the following: my weight = 108 lbs crouching distance (the distance from my regular height to where I crouch) = 90.6 cm jump height = 60.4 cm I first converted lb to kg, and I got 49.09 kg. I then used this value for w = mg and inputted 9.80 for g...

If a plane departs from the North Pole (where the Earth's rotation speed around its axis is 0 Km / h) on the median line to Romania, around the 45th parallel (where the Earth's rotation speed around its axis is 1178, 80 km / h) would the plane reach its destination only by flying to *South* (...

Here I have some problems. I get confused when it says"with respect to the path", is it different from "with respect to the earth"? Because the path is on the Earth. Then, the vehicle is not accelerated in the vertical direction because it moves along the path, is it?

I am just not sure if I did this properly. My professor hasn't really gone over when to use the range equation but I would assume range would equal the distance traveled therefore can be used for this problem. If not the how would I go about solving this? I did 1/6*9.8=1.63 for g on the moon...

Summary: I'd like to know if anyone else thinks of these things <mentor moved to general discussion> What if one day we can "warp" x light years away from Earth, build an enormous telescope, and look back at the Earth x years ago with resolution that rivals the American flag on the moon? Do...

Hello. I was wondering if the any astronomers, professional or amateur, could help me with a few questions about red dwarf stars. The main query I have is the one heading this thread - what (or which) is the brightest red dwarf that can be seen from here on Earth? Associated questions on this...

Summary: What if the Earth would have spin around itself twice as it's speed? What would have be the consequences? How would has it affect the climate and living things?

I'm tasked with drawing the trajectory of the Moon around the Earth (in 2D), taking into account the fact that the trajectory also undergoes precession, so the elliptical orbit rotates about it's center (I think it should rotate around the Earth-Moon barycenter, but for the first step I...

I think this question is important so posting it here. To cut a long story short there is a person in our country who is totally anti-science and anti-Western citilization. He says science is a big lie. < remainder of post deleted by moderator >

In this video, around 2:28 He explains Earth maintain its same angular momentum even after sun disappears. I didn't get it. How Earth maintain its same angular momentum even after sun disappears?

Let us suppose a spaceship moving from Earth to another star that is 10ly away with a speed of 0.99c. Calculate the of years spaceship takes to reach its destination (a) in the rest frame of an observer on Earth and (b) as perceived by a passenger on board the ship For (a) I find that ##t_0 =...

I found this link off of a politically charged website (of the persuasion to deny that Global Warming exists), so I am apt to be skeptical. (The website is hosted at the Northern Marianna Islands, making me even more suspicious.)...

I want to write as sci-fi the first 50 years of the my life where I had the most extraordinary experiences. Need to let them out to release some steam. I'd like to know the following: 1. If the title of your sci-fi book has Jedi written on the title but inside is another story not related to...

I am sure this will become a 'face-palm' moment, but can anyone point me in the direction of what electromagnetic energy wavelengths on either side of the visible spectrum, that is detectable on earth, ie what is not filtered by our atmosphere? I am specifically trying to find information on the...

Summary: I am assuming that there is a database somewhere listing all of the galaxies which astronomers have found. If that is correct, my question is: What fraction of these galaxies in the database have a distance from Earth value associated with it, other than a distance based only on the...

I seek recommendations and testimonials for books that enumerate the unique factors of the Earth-Moon system that gave rise to life on our planet, its place in the solar system, and the solar system's place in the Milky Way galaxy. If you have read any books on that topic, I would appreciate...

My question is, given that the height of geostationary satellite to be 35786 Km and radius of about 6378km determine the area covered by a geostationary satellite Or deteremine minimum number of geostationary satellites requires to cover whole earth. Regards thanks a bunch :)

Could you prove to me how one might calculate things like mass, gravity, distance, of the sun, moon and Earth, very quickly, with only some basic knowledge. Such as 365.25 per year, min, avg and max times for the moon to complete a lunar phase 29.26,29.53,29.8). I'm attempting to understand how...

I've recently been interested in how much energy the Earth intercepts from the Sun; the answer, unsurprisingly was an astronomical amount, measuring quite easily into the ZetaWatts. However, the maths that got me that answer got me thinking... you can use the same method to determine the amount...

In the early 17 th century people argued that the Earth can't be rotating because the don't feel any movement. How fast would the Earth have to rotate for us to feel the effect of rotation and have no doubt of its rotation?

I've reviewed my bookmarks and found some helpful online tools. Please report broken links to a moderator. Additional - serious and not-so-serious ones - should be added here, so please get in touch with a moderator. Links checked: 07/06/24 Latest Update: 08/06/24 (LaTeX previewer) Time...

Do geostationary satellites move with the Earth's orbit or do they not move at all?

If I had an object in an orbit around the Earth that I kept continually shaded from the sun, how cold would it get? Assuming the shade device was not physically connected to and was sufficiently far away from the object to not radiate any heat to it. And if I actively adjusted how much shade...

Hello ,my name is Damon and I'm new to this site so please forgive me if I'm not following the rules to the letter. Could someone please provide a link or CGI model of our Earth' three separate curving, spinning,(while corkscrewing) ellliptical, linear paths, while traveling at speeds of...

Earth has GPS, GNSS and more I guess. Will there (eventually) be a Navigation system for our Solar system so that autonomous (and manned) flights can move around like we do in our vehicles with an onscreen map. Not trying to be fanciful here just wondered if there are discussions or papers. I...

I need to make an integral to fine the speed of the earth. Say the radius is 6378137 meters. How would I account for things closer to the axis that have a radius of 0.0001 meters? I don't think I can just take the speed at the radius. So I found that the Earth rotates at 6.963448857E-4 revs/min...

A bunch of years ago, I read about a very small object following Earth in the same orbit, but not in any danger of collision with Earth (at least in the next few billion years). Anyone know about the object. I have done a search but cannot find any reference to what I think I read about?

So I found the linear velocity by using the circumference of the Earth which I found to be 2pi(637800= 40014155.89meters. Then the time of one full rotation was 1436.97 minutes, which I then converted to 86164.2 seconds. giving me the linear velocity to be 465.0905584 meters/second. I know that...

Assumptions: 200+ years from now Asteroids have been moved to all Lagrange points, and at least 90, 180, and 270 degrees on Earth's' orbit for mining, and shielding humans and equipment Tech to acceleration/decelerate at 1 gravity without need to carry fuel. (My main fiction.) Direct line of...

So, I have had a bit of a look around and can't come up with a concrete answer, so I thought I'd post my curiosity on here! What is the direction that a compass points in 3 dimensional space, and how is this affected by proximity to North? to clarify what I mean: We all know that compasses...

https://phys.org/news/2019-01-planetary-collision-moon-life-earth.html The claim is that was how the excess Carbon, Nitrogen, and Sulfur arrived in the Earths crust, without them being in the core. For instance the Carbon/Nitrogen ratio of 40/1 is twice the 'expected' value.

This is an inverting amplifier incorporating an ideal op-amp with infinite open loop gain. I have a simple question concerning the derivation of its gain (-R2/R1). The point I circled is at 0V (Virtual Earth) but then, if V+=V-, Shouldn't Vout=0 regardless of what R2 and R1 are?? What's wrong in...

Hello learned people, I've been looking at special relativity of muons formed in the upper atmosphere... If I can summarise what I do understand (i think)... A muon has 12km to travel to the Earth from the atmosphere at 0.994c. Alice records this as taking 40.2 micro seconds. Now a muon has a...