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

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5
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2answers
82 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 ...
2
votes
1answer
84 views

How do you find the altitude of the Sun if you are on the Moon?

The question is: If you stand on the equator of the Moon, at midday your position occurs when the Moon is located at the line of the node. What is the altitude of the sun at that moment? ...
2
votes
0answers
86 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 ...
11
votes
3answers
356 views

Will Saturn's rings become a moon?

Planets form from disks of matter orbiting around a star; some moons form from disks of matter orbiting planets. If this were going to happen around Saturn, approximately how much time would it take?
4
votes
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 ...
11
votes
1answer
284 views

If the moon wasn't receding from Earth, what would be the impact on the weather and tides?

Moon is slowly receding from Earth, which means that after its formation it was much closer to the Earth than now. How would weather look like if it wasn't receding at it would be now as close as at ...
2
votes
1answer
171 views

Look up current positions and velocities of solar system objects

I am working on an orbital dynamics code and, for fun, I would like to model the Sun-Earth-Moon system with my code. I can look up the masses of each object just fine, as well as average distances ...
0
votes
1answer
78 views

where is the boundary between dark night and grey night

Is there a clear cut between them? How long and how bright will the moon be for a dark night? I googled but could not find a definition for them. People just talk about them empirically?
3
votes
0answers
36 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 ...
2
votes
1answer
95 views

Visibility of earth from moon during day-time of moon

Inspired by this question. I am curious whether earth, besides being nearly fixed on one place on the moon's sky, is it visible during the day-time on moon too? My understanding is that earth should ...
35
votes
4answers
5k views

How does the Earth move in the sky as seen from the Moon?

I just want to be sure I am visualizing this correctly, because it seems odd. The Moon is tidally locked to the Earth but there are wobbles to its motion due to libration. So from a point on the ...
5
votes
2answers
820 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 ...
11
votes
1answer
3k views

Is the moon moving further away from Earth and closer to the Sun? Why?

According to The NASA Moon Facts page: The moon is actually moving away from earth at a rate of 1.5 inches per year. Why is the moon moving further away from the Earth? Is this a result of the ...
1
vote
2answers
166 views

Why does the face of the moon 'sync' with the earth? [duplicate]

We never see the dark side of the moon. It rotates so that the same side always faces us. I heard two (dinner party) theories on this: 1. The moon was made by smashing out a chunk of the earth, and ...
4
votes
2answers
1k views

Will Earth lose the Moon before the Sun goes into supernova?

Ive read on some sites and saw on youtube videos that the moon is getting away from earth by 1-3 cm a year. Is this enough to make the Earth lose the Moon before the Sun goes into Supernova? Im ...
2
votes
3answers
2k 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 ...
-2
votes
1answer
720 views
4
votes
1answer
110 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?
2
votes
2answers
874 views

What is the angular diameter of Earth as seen from the Moon?

...today I must have left my brain home. I know it's a simple calculation but I keep failing simplest calculations today. What is the angular diameter of Earth as seen from the surface of the Moon?
2
votes
0answers
55 views

Mapping selenographic coordinates onto a sphere

I have a 3D rendering of the moon, which is represented as a sphere with a radius of N pixels. I also have selenographic coordinates. For example, the coordinates of the Apollo 11 landing site are ...
5
votes
1answer
89 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 ...
1
vote
1answer
270 views

Is it possible to see a moonrise or moonset twice in a day?

I've been wondering this for quite some time. Due to the variations in tilt from the earth we know that moonrise/moonset times vary. Is it possible that in any location on the earth one might see ...
1
vote
0answers
56 views

Observed sun/moon rise/set times to nearest second?

Where can I find a list of observed (not computed) sun/moon rise/set times to the nearest second, along with the location (latitude, longitude, altitude [or enough information to find these three ...
9
votes
1answer
168 views

During an eclipse, does the size of the moon and sun match perfectly?

During a lunar or solar eclipse, from our perspective when we look towards the moon and the sun is behind the moon, does it fit exactly? Has anyone calculated the sizes of each in a relative ...
2
votes
1answer
734 views

Is a spotting scope or binoculars a better choice for astronomy?

I'm interested in observing the moon and planets, and maybe some nebulae and star clusters. I have a pair of binoculars: Nikon OceanPro 7x50 binoculars (around \$300) Celestron 20x80 binoculars ...
2
votes
2answers
150 views

Why does the Moon sometimes look Yellow?

My friend and I both noticed that the Moon looked yellow Yesterday, but it wasn't like that the same time the day before, as far as I remember. Does the Moon sometimes look Yellow? If it does, why ...
7
votes
2answers
517 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.
4
votes
1answer
133 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 ...
3
votes
2answers
37 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
votes
1answer
56 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 ...
1
vote
0answers
81 views

Multiple apparent lunar eclipses last night

I saw something very strange last night that I'm hoping someone can help me explain. I was sitting on my roof with a night-cap at about 3am last night. The moon, about the last quarter, was low in the ...
2
votes
2answers
93 views

The face of the moon at moonset

It appears that the face of the moon "rotates" clockwise from the time the moon rises to the time it sets. Tycho's crater seems more to the left and the "Rabbits head" looks like it's facing down ...
6
votes
2answers
274 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 ...
8
votes
1answer
2k views

Finding the solar noon based on longitude and latitude?

Please could someone advise the best method of finding the solar noon based upon location? http://pveducation.org/pvcdrom/properties-of-sunlight/suns-position The stuff on here has been helpful but ...
2
votes
3answers
92 views

Date and time system on moons

Supposedly, if humans were to establish a colony on one of the moons of a planet (such as gas giants in our own solar system), how could we possibly design date and time system? On Earth, we define ...
10
votes
3answers
514 views

Is it a coincidence that both the sun and moon look of same size from earth?

The sun is huge when compared to moon. Despite the huge difference in their size and distance from earth, Is it purely coincidental that they both look almost the same from earth?
2
votes
2answers
4k views

Why don't stars move in the night-sky as the moon does?

I want to know why don't we see a change in the position of stars during the night while we do see a change in the position of the moon. I've checked other online sources and some answers say that it ...
2
votes
1answer
161 views

Connection between Earth, Moon, Theia, and astroid belt?

Are there other fragments aside from the Moon that resulted from the collision of Earth and "Theia" (as it's called in recent main-stream press stories)? And if not, why not? And what happened to ...
9
votes
2answers
307 views

Is there any point on earth where the moon stays below the horizon for an extended period of time?

When I was teaching a class why the earth has seasons today, I mentioned how the poles of the earth experience months of daylight and darkness. Then one of my students asked whether the moon ...
7
votes
2answers
5k views

Why can we sometimes see the moon during the day?

At some points in the year, the moon at my location can be clearly visible during the day. Why is this? If it is any help, I live in Alberta, Canada.
2
votes
1answer
232 views

Are these facts about moon true?

I don't have much knowledge of Astronomy but today I was googling randomly and found an article, according to which: The moon is of the wrong size for its current orbit. The moon rings like a ...
1
vote
1answer
111 views

Would an ultra bright moon indicate that the world is ending?

There is a sci-fi television episode that shows a man looking out the window into the night sky. There up in the sky is the moon, and it's extraordinarily bright. The man spends the rest of the night ...
3
votes
2answers
82 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 ...
5
votes
2answers
1k 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
2
votes
1answer
161 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 ...
8
votes
3answers
270 views

Is the rotation of the Sun and the rotation/orbit of the Moon around the Earth a coincidence?

While looking at sunspot information in connection with Amateur Radio, I found that the Sun rotates on a period from 27 days to 31 days. Its rotation is differential, at the equator it spins at a ...
1
vote
1answer
90 views

Orbital Elements Transformations

I'm a third year undergrad, and for the project I'm doing this summer, I need to figure out the Earth's position and velocity from the moon's point of view. From the reading I've done, it seems like ...
4
votes
0answers
25 views

Any new info about solar flares hitting the Moon added by the LADEE mission?

This article from 2011 mentions simulations about the sputtering effect caused by a solar flare hitting the Moon: "We found that when this massive cloud of plasma strikes the moon, it acts like ...
3
votes
5answers
134 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)?
38
votes
4answers
6k views

Is the moon only 60 pixels?

In doing research on vision, I have learned that "20/20" vision corresponds to a visual acuity of being able to resolve details 1 arcminute in size, that most people have around 20/15 vision, and that ...