Moon Definition and 1000 Threads

Mentors' note: This thread has been split off from https://www.physicsforums.com/threads/viewing-distant-celestial-objects.997168/ If it were possible for Hubble to have seen evidence of Moon landings, those batty conspiracies about the landings being fake would have died long ago.

So, I decided to do Fg=ma I tried 25(9.8)=1.62m m= mass However, when i did it i got a mass of 151 but when i put it into its separate equations, the fg is not 25x larger so fg=ma fg=151(9.8) = 1479.8and then fg=ma fg=151(1.62)= 244.62 but 1479.8/244.62 is not 25 it ends up being 6.05...

https://www.nasa.gov/press-release/nasa-s-sofia-discovers-water-on-sunlit-surface-of-moon/

The equation that governs the period of a pendulum’s swinging. T=2π√L/g Where T is the period, L is the length of the pendulum and g is a constant, equal to 9.8 m/s2. The symbol g is a measure of the strength of Earth’s gravity, and has a different value on other planets and moons. On our...

If I wanted to create a factory, possibly automated, on the moon using materials from the surface to create silicon solar cells how hard would it be? Considering the environment, the cheapest and simplest solar cell, regardless of efficiency, would be what to use because quantity and area of...

1. Since the gravitaional field strength is 1/6 of that on Earth: W=mg W=90*9.81/6 W=90*1.635 W=147.15 ~ 147 N 2. ∆Ep=mg∆h ∆Ep=90*1.635*50 ∆Ep=7357.5 J I do not now whether this method would be suitable and if I should have instead used the formula for gravitaional Potential, V grav=-Gm/r? 3...

Asimov pointed out that Earth's Moon is nowhere concave (looped) in its motion with regard to the Sun. What about Pluto and Charon - are both concave w.r.t. the Sun at certain times? Moreover, what is the largest body in the solar system which is sometimes concave w.r.t. The Sun? Thank you...

Hello, I thought that it was easy to calculate the difference of aging on different planets, just by knowing the difference of gravity between them. But it is not so easy... I will also consider that the difference of gravity will not reduce our age because of other reasons (on muscles, on...

Apologies in advance if this has been touched before. If the Earth has 81 times the mass of the Moon, why the Moon has 1/6 of the gravity of the Earth?

During an eclipse the Moon covers the Sun.However this shouldn't be happening due to gravitational lensing we should be able to see some light? Is the mass of the Moon not big enough or photons do reach us but they are so little our eyes can't detect them?

I went to the usgs site and found the pdf, but for some reason I could not enlarge the file to read it. Any body got a link to the map with a legend? TIA.

I was reading this: http://www.physics-astronomy.com/2020/04/set-your-alarm-jupiter-venus-and-moon.html It seems that for this to happen the Moon would need to be in-between the pair of planets and the Sun - but the Sun's path defines the Ecliptic, and the bright planets are all very close to...

Sigh. Here's USA Today: https://www.usatoday.com/story/news/nation/2020/04/02/pink-supermoon-full-moon-coming-tuesday-april-7/5115114002/ Here's my local news: In both cases, they describe it properly in the article/report, but I guess they got to have that clickbait/headline grabber. The...

Yup, they all appear together pre-dawn on March 18 to the SE. The planets hang out together for a week or so, while the Moon moves on. https://www.news4jax.com/weather/2020/03/16/you-are-missing-planet-palooza-if-you-dont-look-up-the-next-few-days/

Here's a little funny story I read in a book written by Carl Sagan, God rest his soul. I can't remember exactly which one, since I read four of his books. I think it was The Demon Haunted World, I'm not sure. But here goes: Neil Armstrong, Buzz Aldrin and Michael Collins were letting off some...

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...

Hello, i am going to buy a laser and a telescope powerful enough to see the laser spot on the moon. The lunar phase i choose for the experiment is New Moon, for obvious reasons. When i move the laser, i should see the light spot move on the moon surface after about 2.5 seconds, due to the light...

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?

Read a story in the Analog, April 1990, issue. The author describes a cooling system for moon tunnels using water that is cooled via large fins on the surface. An explanation is given that rock is a poor conductor of heat and eventually equalizes. And therefore the need for cooling. Why would...

I am interested in the following thought experiment: an apple falls from a tree on Earth. Does the moon move (although slightly)? I can see an argument for it doing so—the center of mass of the Earth has moved slightly away from the moon, so the moon would feel a slightly smaller force and would...

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...

Suppose we are driving on moon (I mean there is not air resistance) at a constant velocity. Suddenly the car goes on an icy land (the friction is zero). What happens? In other words, if we drive at constant velocity and there isn't air resistance, Is there any friction force between tires and...

Drove up today to The Museum of Flight in Tukwila, WA ( a 3 hour drive) to see their temporary exhibit to honor the anniversary of the Moon landing. First up, Major Matt Mason! They had a collection of space related toys from the time, and I couldn't resist snapping a photo, as I had one as a...

Summary: Last night's View of the Moon from Northern Illinois Even with a few day-old waxing moon I was able to easily see all of the moon's outline. As the moon set last night it lined up with the street I was on making it appear vastly larger than normal. I was in awe as it drop down.

I found an strange phenomenon while observing the moon. When the moon is seen through the window screens, strange light lines will appear: Half open screen: Closed screen: Why is this happening? I saw similar things on street lights, car headlights, etc through screens.

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...

Quick question for the people to better understand orbital mechanics. Due to large mass concentrations on the moon's surface, there are only four orbital inclinations that a satellite can be at to maintain an indefinite orbit: 27°, 50°, 76°, and 86°. My question is this: If a satellite was...

This is the official thread for my scifi project Blood Moon (running name, likely to change) **Since my earlier thread got moved here, I might as use this new thread as a starting point for the whole project, and limit usage of the other threads for more specific inquiries about certain...

So here is a serious question: If Pluto isn't big enough to be a planet, then wouldn't it be a moon to Sol. I mean, a planet can have a moon. A moon can have a moon. So can a sun have a moon? Is there actually a rule? Inquiring minds want to know.

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...

Why is there a difference in force required throwing a ball horizontally on the moon and pushing it horizontally it in the spacestation Thanks

Just interested in what may be achieved by putting a man/men on the moon again.

From Earth, we always see precisely the same half of the moon. Isn't the simplest explanation for this odd fact that the Moon's core is not uniformly dense, and it's centre of gravity is situated some distance further way from us than its geometric centre but on a direct line extended beyond...

I am evaluating the possibility what magnesium may be the most-easily obtainable structural material on Moon. The following ISRU sequence is proposed: 1) Regolith melt electrolysis produce ingots made of ferro-silicon, as by-product of breathable oxygen production 2) Ferro-silicon ingots are...

Sorry, I feel stupid posting this but my family is having a big debate right now and I was forced to open Physics Forums. So I personally believe the moon landing was real, my sister believes it was fake. The evidence is convincing on this video I watched. It was something like "Conspiracy...

Hey, I was wondering. If the Earth exerts a force on the moon and the moon exerts an equal but opposite force on the Earth (Newton's third Law of motion), do I also exert a force on the moon since I also have mass and therefore, the moon would exert a force on me (equal, but opposite). Also...

I am thinking to use the moon as a satellite for my IOT gateway. Let's say I have a gateway that collects data from my sensor nodes but it has no internet access. Using moonbounce(EME), it will send the small data (few bytes) to the moon then reflect it to a ground station with internet...

Assuming it happens and that the Deep Space Gateway happens as a base for Moon landing and further exploration. What sort of orbit would it have in relation to this use? I have I-searched but not found any detail. Thanks.

I know this may be extremely basic to almost everyone on the forums, but I really can't tell if moon cycles are predictable or not ! like can we tell in advance when is the full moon ? I feel like the answer sould be a definite YES, but my confusion is based on what I see each year. I live in an...

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.

(For reference, I am around coordinates ( +30 , -90 ), and this is the January 2019 lunar eclipse.) I am typing this at supposedly mid-eclipse, and yet I see a thin crescent of white (ash?) along one side. It seems that the Moon should be well within the umbra at this point.

A person of mass 60kg will weigh around 100N on the moon. This is roughly equivalent to the gravitational force on a 10kg object on Earth. Even if the forces acting on both are about the same, we don't see 10kg objects floating around on Earth whereas a man weighing 60kg can easily float on the...

I can find public information about the speed of the moon at max and min distance from the Earth (Ap vs Per) but how do I find the same information for the Earth's velocity around the same barycentre? The Earth's orbit around the barycentre is it a perfect circle or is it an ellipse? If it's an...

Is there an easy way to explain this to a 3 year old?

I'm working on a story set on the moon post-industrialization. The moon has an orbital ring with a spinning exterior to simulate Earth gravity. People work on the surface in lunar grav, then go up to live on the ring under conditions more favorable for human bodies. Two questions I need to...

Homework Statement Somewhere between the Earth and the Moon there is a point where the gravitational potential due to the Earth exactly equals that due to the Moon. i)At what distance from the Earth is this point? Mass of Earth = 5.98x10^24 kg Mass of Moon= 7.35x10^22 kg Distance between...

I'll attach a picture of what I mean but essentially I wanted to know if it was possible to (under circumstances where the Earth and moon do not change angle of rotation when orbiting the sun) create a perpetual motion machine using orbit as a means to turn a giant gear circling the Earth in...

Hello all! I am trying to make a VISUAL model (in C#) to predict lunar and Earth eclipse periods for a satellite that I have accurate ephemeris for. I want to calculate everything in ECEF reference frame. How would a go about modeling this system to the accuracy I'm interested in? I assume I...

What is the difference between man-made satellites and the moon that causes the former to drift towards the Earth but the latter drift away?

Former 'Mars czar' in a Phys.org interview: Read more at: https://phys.org/news/2018-08-mars-czar-latest-news-red.html#jCp But would it? Surely the Moon is a perfect launchpad for Mars, a testbed, and a supply base? Going from Earth direct is a truly huge task. From an established Lunar...