Lunar Definition and 109 Threads

A problem with the SETI search is it looks for a specific radio frequency and even worse it has to be directly pointed at us to be detectable. We can’t from Earth just try detecting normal radio signals like we put out with radio, television, cell phones, etc. because from other planets it...

Has NASA considered building a maglev on the moon so we can use the lunar mass and momentum to gain higher energy savings for missions to Mars and beyond? A spacecraft can be catapulted toward the destination with its rocket engines off and only turn them back on to course correct or slow down...

I mean - when they form. What are typical gas densities at lunar crater rim when the crater is made by a comet? An asteroid? Both a comet and an asteroid, hitting Moon at several km/s, initially heat up to several thousand K, and even asteroid produces some vapour... at hypocentre. However, by...

The wikipedia article on Lunar distance contains a confusing graph. The graph seems to suggest that the eccentricity of the lunar orbit is maximal in january and ~july, and minimal in april and ~october. I think the eccentricity should be constant. Is wikipedia right or wrong, or is there some...

I have been trying to find a time lapse animation showing lunar libration made of actual real photographs of the Moon. However, no matter how much I search, I can only find computer-rendered animations. Does anybody know of a video made out of actual photographs of the real thing?

I'm currently working on a pet project which is similar to the OpenAI Lunar Lander v2 (hence the problem is in a 2D context), and seeking help for a sub-problem that's been blocking me for a while. At any instant of time, I'm to find Fe: magnitude of main engine thrust, must be >0 Fs...

My simulator is trying to mimick the actual conditions of the Apollo landing. I have entered in numbers for my runge kutta simulator for LEM mass, dry mass, fuel, thrust of the rockets, fuel burn rate per second etc etc. But I am not able to land, only very close to landing. I copied the...

What is the delta-v requirements from each of the Earth-Moon lagrange points to landing on the lunar surface? What would be the best software I could use to visualise and calculate that kind of thing? Thanks.

https://www.sciencealert.com/check-out-this-amazing-plan-to-turn-a-crater-on-the-far-side-of-the-moon-into-a-radio-telescope Original article from NASA: https://www.nasa.gov/directorates/spacetech/niac/2020_Phase_I_Phase_II/lunar_crater_radio_telescope/

This video has been popping up in my feeds over the last day or so, as I'm sure others here have also seen it by now. Looks like it has been taken with one of these super zoom cameras. After watching it carefully several times, it doesn't appear to be done with creative video editing, which I...

Hello- I was looking at a table of the dates of lunar perigees for 2020, and I noticed that most of the perigees were between 27 and 29 days apart. So the perigees do not appear at a constant frequency, which I did not expect. There are even a pair, between June 30 and July 25, which are...

Anyone else watching the lunar eclipse tonight? It starts at about 9:30PM EST, with totality at 11:41. It's cold and windy in PA, but at least it's mostly clear. Here's a couple of pre-eclipse photos:

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...

I have recently been reading To Explain the World: The Discovery of Modern Science by Steven Weinberg. I am currently in the midst of Chapter 7, Measuring the Sun, Moon, and Earth. On Page 66, Weinberg comes to "what in some respects is the most impressive example of the application of...

Can total lunar eclipse and partial lunar eclipse be happened at the same time? So, do we call it partial lunar eclipse when the total lunar eclipse happen just before?

The period of the lunar apsidal precession is about 8.8506 years measured against fixed starts. How can I accurately convert this to the period between alignments with spring equinox? Thanks.

Hello, I don't see any other post about tonight's full moon and lunar eclipse, so I thought I would mention it.

I'm attempting to use an algorithm translated from Jean Meeus: Astronomical Algorithms. The algorithm in question finds a geocentric position of the moon given a certain day. I have been able to find the geocentric longitude of the moon, but I don't know what this longitude is in reference to...

Does anyone know how long the lunar month was when the moon was formed? I can't get the equation to work. I'm looking for speed of the moon when it was created at about 1/10th the current distance from the earth. Thanks.

http://en.wikipedia.org/wiki/Lunar_lava_tube Given that they are expected to be at about -20C and parts of them will be in permanent darkness. If ice can exist at the Lunar poles: http://nssdc.gsfc.nasa.gov/planetary/ice/ice_moon.html then why not there? If water molecules migrate from the...

I recently came across this article (from 2005) outlining a proposal for a lunar space elevator: http://www.niac.usra.edu/files/library/meetings/fellows/mar05/1032Pearson.pdf Their is nothing in the article which stands out to me as being unrealistic, although the cost estimate ($10B) might...

Disclaimer: The questions below were raised by an article that's most definitely pseudoscience. The questions themselves have nothing to do with what makes it "pseudo", though, so don't let that put you off, please. :)Quoting from [crackpot link removed by mentor] (I'd advise you only to read...

Homework Statement I'm trying to figure out the surface area on a 5 sided shape where the sides can all be modeled by "lunes". The shape will end up looking like a banana peel. We are modeling the sides of the shape as lunes with varying angles on a sphere of radius 3 inches. I'm trying to...

Greg Bernhardt submitted a new PF Insights post The Moon Quiz Continue reading the Original PF Insights Post.

My first question is: Shouldn't the lunar phases be thrown off by Earth's orbit of the sun? As in, after 6 months of orbit, since we are on opposite sides of the sun, the phases would be reversed so that the moon being in the same position relative to the Earth as it was before the 6 months...

Good morning, I was wondering if someone can help me in this subject. I recently programmed the entire ELP2000-82b lunar theory in a dll. My problem is the reduction of the obtained positions to the mean equinox of date. The theory is referred to the ELP2000 inertial frame. A simple adjustment...

I'm still working on understanding some of the subtleties of the lunar orbit. We know that the lunar nodes ( where the lunar orbit crosses the plane of the ecliptic ( a cryptic term for the plane of the Earth's orbit.)) shift progressively and complete a cycle in 18.61 years: the period of...

Over the last year or so I've been doing quite a bit of reading trying to find out what is actually causing lunar nodal precession. There seems to be a lot of handwaving but no definitive answer, which I find rather odd. Maybe I've just not found the right source. Google seems obsessed with...

Hi there, The University of Arizona has these two institutes (among many others, of course): - Lunar and Planetary Laboratory, LPL for short - Steward Observatory As far as I understand, both are into space research and astronomy. If I wanted to join either one or the other, I would have no...

Below is the link to the Lunar super eclipse Sept. 27th. It won't happen again until 2033. http://finance.yahoo.com/news/theres-rare-supermoon-total-lunar-205421688.html?amp;soc_trk=ma&soc_src=mail&soc_trk=ma

Homework Statement Using the PhETLunar Lander applet, we are to find the mass of the lunar lander. We know the maximum acceleration of the module's engines and gravitational acceleration of the moon. Homework Equations F=ma mgh=1/2mv^2 f*t=p The Attempt at a Solution Everytime I try to...

Head's up, as this scientific finding is making the rounds. http://www.cnet.com/news/the-moon-is-shrinking-and-the-earth-is-shaping-it/ The claim is that the oriented gravitational pull shapes the landscape of the moon. Except for the established effect of tides, it's odd that scientists do...

Hi, Just wondering: The lunar orbit around the Earth is tilted 5.1 degree with respect to the Earth's orbit around the sun (as described in the video), so only at 2 times during the year the Earth is aligned with the sun such that lunar eclipses can happen IF the moon is behind the Earth...

the Moon is currently very close to Venus and Jupiter in the sky this pic I did last nite 20-6-2015 Tonite the Moon will have moved eastwards ( to the right) and will be directly above Jupiter cheers Dave

Homework Statement A lunar lander is descending toward the moon's surface. Until the lander reaches the surface, its height above the surface of the moon is given by y(t)=b−ct+dt2, where b = 770m is the initial height of the lander above the surface, c = 62.0m/s , and d = 1.02m/s2 . Part B...

hi guys and gals a total lunar eclipse will be visible for all Pacific and parts of it for most of USA parts of South America, Central Asia cheers Dave

1. I have a physics problem that I am having trouble understanding. Here it is: Your lunar lander (with fuel and crew) has a mass of 14,700 kg. It is initially in a circular orbit around the Moon (i.e. Viy = 0 m/s) at an altitude of 30 km above the lunar surface. To land on the Moon, you...

Why does the farside of the Moon have a thick crust with a landscape dominated by lunar highlands while the nearside has a much thinner crust with a landscape dominated by maria? This is what the authors of a paper recently published on the arxiv (and accepted for publication in the...

Homework Statement Find the radii of the umbra and penumbra circles drawn drawn perpendicular to the EMS axis, formed at a distance equal to that of the moon from the Earth. Homework Equations (From: http://www.opticiansfriend.com/articles/equations.html#Shadows) D2 / L1 = (P + U) /...

Homework Statement To protect the lunar base against space and sun radiation, astronauts covered it with 4m thick layer of regolith (moon soil). However, they found that they level of radiation was still 50% higher than on the Earth's surface, which they want to match. How many more meters of...

http://www.sciencemag.org/content/early/2013/05/29/science.1235768 This is the result of fine-grained mapping of the gravity anomalies on the moon. They propose a bulls-eye model of impacts to account for the anomalies. I'm not competent to judge. The idea appears interesting to me.

If a satellite tries to land on the moon without rockets to counter the force of gravity, it comes in too fast and crashes into the surface destroying itself. A satellite would be orbiting at approximately 1.8 km/s or so at a 50km altitude, and come in for landing from that height which would...

Lunar Gravity, On the moon, the acceleration due to gravity is $-1.6m/s$ . A stone dropped from a cliff on the moon and hits the surface of the moon $20s$ later. How far did it fall? What is the velocity at impact.? well here I presume since the rock is just dropped that $v_0=1.6m/s$ but the...

If during a solar eclipse the moon tapers one moon diameter, wouldn't a lunar eclipse taper one Earth diameter?

Homework Statement I am currently working on a computer science program which calculates the landing of a craft on a given planet. The user will enter in various known variables. I need some direction on what formulas to use for my program. I am strong in computer science however I...

I have done some reading, and found articles with little to no references (to scientific journals) that proclaim that although humans are mostly water...the moons gravitational pull has very little, if any, effect on our bodies. I don't believe that there is more crime during full moon's, for...

I am interested in knowing a little bit more on what would be the wisest way to create a lunar robot with the proper shielding for lunar conditions to do things like mining and lunar exploration. Also what kind of batteries would be best for these conditions? Also, say that there are robots...

I would like to know what the effects of a solar flare would be on equiptment used for lunar exploration, say a robot to be specific. What kind effects would this have on the electrical system? I also read a NASA article describing a large solar flare that created a long enduring proton...

Being on the east coast of the US, I won't be able to see it. Those on the west coast will though. Here is how it will happen. Once in a blue moon, the Earth darts out of its orbit temporarily and blots out the sun. When that happens, you can see all of the sunsets on the Earth reflected off the...

So I am doing research for the different energy sources that might be available for a space base in about fifty years from now. Some of these energy sources would likely be solar, fusion, fission, Nuclear, and I heard of radio - nuclide as well. What else could be used? In addition, does...