Questions regarding Luna, Earth's moon and only natural satellite.

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3answers
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Red Moon a Characteristic of all Total Lunar Eclipses?

I understand that the redness of the moon during the total lunar eclipse last night/this morning (April 14-15 2014) is a reflection of the red light caused in earth's atmosphere due to Rayleigh ...
6
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1answer
241 views

How far apart can two people watch the moon simultaneously?

Obviously there's a limited part of earths surface where the moon is visible at any given time. I imagine the area of this surface would be a lot smaller than the area where the sun is visible at any ...
6
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2answers
582 views

How to calculate the altitude of the Moon?

With the known latitude coordinate of the observing position, how to find the altitude of the moon when it is high, i.e when it crosses the local meridian?
6
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1answer
54 views

Is there a pattern between the mass of a body and the mass of orbiting objects around it?

I was looking at Wikipedia's Solar system page, and it says that Sun represents 99.86% of the whole solar system mass. I found that pretty huge. So i calculated ratio of masses : Earth / (Earth + ...
6
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2answers
394 views

Is it possible for a person to not see the new moon at different places on earth?

It is known that theoretically we see the same moon phase everywhere on the earth, but practically I see that people are unable to observe the 0.8% waxing crescent at different places on earth. This ...
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4answers
4k views

Why did the moon abruptly change positions in the sky?

Three or four weeks ago I was outside showing my neighbors how cool the moon was through a 'backyard' telescope in broad daylight (~8PM PDT). It was 3/4 of the way across the sky (setting behind the ...
5
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2answers
801 views

Why does the Moon never set in Svalbard, Norway?

I heard in a documentary that, in Svalbard (Spitsberg), Norwegian archipelago in the Arctic Ocean, the Moon never sets. Why? A drawing would certainly help.
5
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1answer
955 views

Why does the darkening of the Moon go from left-to-right during an eclipse?

In anticipation of the upcoming April 2014 lunar eclipse, I decided to use the 3D virtual planetarium software Stellarium to simulate what it is supposed look like where I live, since I've never ...
5
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2answers
973 views

Why can I see the whole moon during various non-full-moon phases?

Here's an image that describes the phenomenon I'm asking about. The very thin sliver to the left is of course the surface of the moon as lighted by the sun. But the rest of the moon is also faintly ...
5
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2answers
129 views

Official Definition of Satellite?

So I had an argument with a friend, which was about whether the Moon is a planet or a satellite. IAU 2006 Resolution B5 gives definitions on what it is to be a planet, but there is a vagueness, as I ...
5
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1answer
337 views

How long until the Earth and Moon become a binary planet?

With the rate at which the moon is further receding into a higher orbit, how long until the barycentre between us and the moon leaves the earth, and going by the IAUs 2006 definition update, we become ...
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3answers
2k views

Is it safe to view moon at daytime through telescope

I have a little 76mm Newtonian Reflector. I want to see the moon at daytime. Is it safe to look at sky at daytime when sun is shinning or there is any risk of sun.
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3answers
180 views

Does the Sun impose back it's tidal forces onto the Earth (such as the Earth's to the Moon)?

It is known that each year the Moon is moving away from the Earth due to tidal forces. What about the Earth relative to the Sun?
5
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1answer
90 views

Red cresent moon

Yesterday night i witnessed something very strange when i looked outside the window. I saw the moon (crescent) but it was dull red and right on the horizon ,which is strange considering that it is ...
5
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2answers
165 views

How unusual is the solar system?

In Isaac Asimov's Foundation series, the main characters are looking for the long-lost Earth. There are two major features of the solar system that seem to make it unusual among the millions of ...
5
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2answers
2k views

Percent-illumination of crescent moon and its naked-eye visibility?

What level of percent-illumination of moon (waxing crescent), given by Stellarium, is enough to make it visible with naked eye, in clear sky? thanks
5
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1answer
481 views

What distance has the moon been from earth at the closest?

For every year, the moon is orbiting further away from earth. What distance has the moon been from earth at the closest?
5
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1answer
117 views

What method is used to calculate the 'quality' of a solar/planetary image?

What sort of algorithm is used to calculate the relative quality of an image, such as is performed by PIPP, Registax, or Avistack? Such applications take planetary or solar images and prior to ...
5
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1answer
653 views

Formulas to determine the illuminated phase and orientation of the Moon

The phase of the Moon (the bright limb) looks different depending on where on Earth the observer is located and the time of the observation. I've located this video and the accompanying spreadsheet ...
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2answers
84 views

Meteorites bring water

The latest information suggests that Earth's water came from Meteorites . The Moon was also bombarded by Meteorites and yet it has no water. Is this because it lacks an atmosphere and its water was ...
5
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2answers
171 views

Tide on the Moon

If the Earth's Moon had a water ocean of depth 2-4 Km, how high would the tides rise due to the Earth's gravity? (Just a hypothetical question.)
5
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1answer
123 views

Is lunar elevation at a given location for a given day unimodal?

Is lunar elevation at a given location for a given day unimodal: Unimodal function In other words, once the moon's elevation reaches a minimum (which may be above or below the horizon depending on ...
5
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0answers
43 views

What implications does younger volcanism have on the Moon's thermal evolution?

In the paper Evidence for basaltic volcanism on the Moon within the past 100 million years (Braden et al. 2014), suggest that features such as Ina (image below) represent a far more recent age of ...
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1answer
312 views

Why can we see stars but not astronaut on the moon

A question came up today in astronomy class and it got me wondering all night. How is it that if stars are so far away, we can see them so clearly but we cannot see astronauts on the moon.
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5answers
164 views

Could there be life beneath the surface of Mars or moons?

I realize radiation and extreme temperatures would probably destroy life on the surface of most planets and moons, but could life exist beneath the surface (e.g. like earth worms on earth)?
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2answers
1k views

What would happen if Jupiter and Earth were at the same distance as the Moon is from Earth?

If Spock came with a super machine capable of moving planets, and placed Earth so close to Jupiter as the Earth's moon, the gravity of Jupiter would make us fall into it?
4
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3answers
317 views

Why do dark objects look white from a distance? (Moon, Ceres, but not Earth!)

What makes the Moon shine white in the sky, although it seems to be as dark as asphalt? Earth's average albedo is 3 and 4 times that of the Moon and Ceres respectively (0.37 vs 0.12 and 0.09). But ...
4
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1answer
189 views

Lunar Soil: what are those “bumps” and how were they formed?

I was watching a video of the chinese lunar landing and saw numerous bumps in the soil. What are they? Is there any theory that explains how they came into existence?
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2answers
169 views

Is there any man-made satellite orbiting our moon?

I am just wondering whether any man-made satellites are currently orbiting our Moon. If there is one, would I be able to see it using my telescope?
4
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1answer
161 views

Do all moons orbit their planets on the ecliptic?

Do all moons orbit their planets on the ecliptic? Do they all follow this same process as the moon that orbits Earth, or is their some random distribution with some even having extreme polar orbits.
4
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1answer
81 views

Venus transending behind the Earths moon December 7, 2015

Observing from Earth what are the odds thats Venus does not line up in conjunction with earths moon and does not transend behind the moon but slightly below or above with a complete visual of venus ...
4
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1answer
155 views

What can a lunar-based telescope do?

What can a lunar-based telescope do? If the band is ultraviolet and it can do high time sampling exposure, maybe it can be used to get distance for a star with stable pulses. However, the star should ...
4
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1answer
87 views

Recommended papers

I am highly interested in how the moon originated. Theories suggest that the moon is a chunk of the earth, or rather, both were at one point one celestial body. Is there any literature out there with ...
4
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1answer
2k views

How bright is the full Earth during the lunar midnight?

At lunar midnight (i.e. the new moon as seen from Earth), the Earth is in its full phase with its entire disk in sunlight, and it is the brightest object in the lunar sky. How bright is it, and how ...
4
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1answer
118 views

Evidence behind Giant Impact hypthesis

The giant impact hypothesis is a theory to explain how the moon was formed. What evidence is there that supports the theory and led us to find the current theory?
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1answer
757 views

Can an amateur astronomer bounce a laser off the moon?

In the TV show "Big Bang Theory" episode "The Lunar Excitation", the gang fires a laser from their rooftop, bounces it off mirrors on the moon, and measures the laser coming back on a computer. Is ...
4
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3answers
591 views

Telescope buying guide for a beginner in India

I am located in the southern part of India and am looking forward to buy a telescope to gaze up to look ay farther planets, moons in our solar system and take pictures. How should I go about getting a ...
4
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1answer
79 views

How did pre-Earth's mass and orbit change at the Moon formation event?

The popular, but still disputable, Moon formation theory is that a pre-Earth was hit by a Mars sized planet. The mass ratio of Earth:Mars:Moon is roughly 100:10:1. Does this mean that pre-Earth was ...
4
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1answer
218 views

Could something temporarily break the Moon's tidal lock?

Would it be possible for something to cause the Moon to start rotating at a different rate, breaking its tidal lock with Earth, without ripping it apart? If so, would the Moon's tidal lock eventually ...
4
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1answer
94 views

Which planet or moon has all resources that can be used to sustain life in a controlled biosphere? [closed]

Now that we are making it to Mars, continuing onward, in an effort for humanity to civilize other planets, not just setting up residential colonies, but to mine minerals and carry on geological and ...
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2answers
118 views

Is extraterrestrial mining more difficult or impractical for bodies without plate tectonics?

This article talks about the possibility of mining Uranium on the moon. Since the Moon lacks the geological forces that have created veins of concentrated minerals on Earth, would extraterrestrial ...
4
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0answers
103 views

Questions about a fictional binary system, and habitability

Note: Questions are at the bottom. The rest had simply been written in a format to better organize my thoughts. The formulas used to construct this fictional solar system, had been borrowed from ...
3
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2answers
117 views

If the moon still had a magnetic field how long would have been possible to keep an atmosphere?

Let's assume the Moon had a considerable magnetic field to prevent the atmosphere dispersion caused by solar wind. Given the low gravity of the Moon, how many years would pass before all the gases (of ...
3
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1answer
219 views

Sum of the Masses of All Moons in the Solar System

I'm looking for the total mass of the moons in the solar system in Earth Mass this would be include the 67's moons of jupiter, the 62's of saturn, the 27's Uranus and the 14's for Neptune. it's a ...
3
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1answer
132 views

Why is a meteorite impact on the moon visible as white light?

You can watch a video of a meteorite impacting the moon at the npr.org website. Why does the impact produce white light? I understand that the impact is like an explosion, but there is no air on ...
3
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2answers
96 views

The RA and Dec of lunar poles

The moon faces the earth with one fixed side. However there is a small vibration. So I am not sure the south and north poles of the moon is fixed. Even if they are fixed points on the moon, the pole ...
3
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2answers
38 views

Why is sodium such a common ion for in ion tails?

I was doing research about ion tails of planetary bodies and noticed that ion tails composed of sodium were common. For example, Mercury and the Moon both have ion tails made of sodium. Why is sodium, ...
3
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3answers
423 views

Why is the outline of a crescent moon brighter?

Some quick googling has given me the answer to whether seeing part of the moon that receives no sunlight is an optical illusion or not: it isn't. Earthshine lights the moon enough for the human eye to ...
3
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1answer
93 views

Supermoon Lunar Eclipse?

I recently read this article: http://www.cbsnews.com/news/supermoon-lunar-eclipse-coming-this-month/ I'm having some trouble understanding how a "supermoon" lunar eclipse is possible. Judging from ...
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1answer
59 views

Can the martian dichotomy (SIH) and the moon's formation (GIH) be related?

If we assume that the Single Impact Hypothesis regarding the martian dichotomy (wikipedia) and the Giant Impact Hypothesis regarding the Moon's formation (wikipedia) are true, then is it possible that ...