Questions about Mercury, the first planet from Earth'd sun. Also the smallest major planet in the Solar System,

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25
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6answers
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Why is the Sun's density less than the inner planets?

The density of the Sun is $1410~\frac{\text{kg}}{\text{m}^{3}}$ and Mercury's is $5430~\frac{\text{kg}}{\text{m}^{3}}$, but shouldn't the Sun be denser? Because when the Solar System was forming, ...
0
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1answer
214 views

Why aren't all planets in the same plane?

Obviously all planets are not in same perfect plane. Because if at all they were in the exact same plane, it would mean that Mercury transits and Venus transits would not be that rare. Any ...
3
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1answer
175 views

Pinhole projector for the Transit of Mercury

Very quick and simple one today. What would be the best/optimal pinhole size for a pinhole projector to observe the transit of Mercury on May 9th? I want to get the optimum between resolution and ...
5
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1answer
169 views

Watching the Mercury transit with improvised devices

I have learned that it is not possible to watch the upcoming Mercury transit with the plain eye (using special filter glasses). Is it possible to watch the transit with improvised devices (like a ...
8
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1answer
159 views

Is it possible that Mercury was originally the moon of Venus after a giant impact?

Mercury looks like the Moon, and so it makes me think about a question: is it possible that Venus and Mercury were the a same planet originally, and a giant impact with that planet made it split into ...
0
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1answer
72 views

Can a human land on Mercury? [closed]

Can a human in a normal astronaut suit designed for the moon, land on Mercury and walk on it's surface. If not what would happen to him/her?
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2answers
220 views

Can we find rocks from Venus or Mercury on Earth?

As we know, we can find rocks from Mars on Earth, how about Venus and Mercury? Is that not found yet? Or it is impossible to find them because they are closer to the sun and derbis won't go far away ...
4
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1answer
148 views

Could Venus or Mercury have a moon that we haven't detected?

Let's consider Mars' two moons for a moment. They're small, not even spherical, and most likely are captured asteroids. They weren't discovered until the late 1800's. Telescopes are much more powerful ...
0
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1answer
74 views

What does the surface of Mercury look like?

What does the surface of Mercury look like? What color is it (I have seen some images portraying it grey and some a light brownish color), and would the surface be dusty like the Moon, smooth, or ...
5
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2answers
213 views

Are there ever any simultaneous transits of both Mercury and Venus as seen from the Earth?

Transits of Mercury happen fairly frequently due to its short period, but transits of Venus are less frequent. I've looked over the data available to me and found that there have been transits of ...
2
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2answers
102 views

Delta-v from Mercury surface to Venus surface

What it says on the tin: using the most efficient launch opportunity afforded by orbital mechanics, what delta-v would you have to impart to a payload to send it from the surface of Mercury to crash ...
7
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1answer
196 views

Are we sure there are no planets inside Mercury's orbit?

Currently, most explorations about new planets are pointing to area outside Neptune's orbit, but how about inside Mercury orbit? Can we say for certain there are no planets inside Mercury's orbit?
4
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1answer
45 views

Do sungrazing comets leave a field of meteoroids near the Sun?

A large fraction (a third?) of all comets found (with observational bias thanks to SOHO) have been sungrazers, breaking up with perihelion of a few of Sun's radius. Is there reason to believe that ...
4
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1answer
116 views

What is the format of the data from the JPL's HORIZONS system?

I'm looking for accurate positions and velocities of the planets in the solar system over several decades. I want to simulate their trajectories using Newtonian laws of motion, and compare the ...
1
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1answer
28 views

attractors of Mercury's spin-orbit relation

Mercury rotates at such a rate that the Sun appears to stand nearly still at perihelion, when the tide is strongest. Is there a mechanism that tends to adjust the orbital eccentricity to improve the ...
2
votes
1answer
525 views

Shall we say now that Pluto is “larger than Mercury” ?

http://pluto.jhuapl.edu/News-Center/News-Article.php?page=20150717-3 "Scientists working with NASA’s New Horizons spacecraft have observed Pluto’s atmosphere as far as 1,000 miles (1,600 kilometers) ...
5
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1answer
153 views

Is Mercury's core liquid?

A very basic question, but one to which I keep finding different answers: does Mercury have a liquid core, or is it all solid? Whatever the reason, what are the causes of it being so?
4
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1answer
94 views

What are the exact physical parameters used to calculate Mercury precession with Einstein theory?

NASA measured 43,13 arc seconds per century. General relativity predicts 42,98 arc seconds per century. I try to find out what the parameters' values such as $G$, $M_{sun}$, $\omega_{min}$ at ...
6
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1answer
52 views

When do Mercury/Venus reach greatest elevation at sunset/twilight for a given location?

On what day does Mercury reach its greatest elevation (in degrees from the horizon) at sunset a given location? The obvious answer is the day of Mercury's greatest elongation from the Sun, but, ...
8
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2answers
225 views

Motion of the sun as observed from mercury

I recently found this animation which shows the motion of sun as observed from mercury. It seems as if the sun stops in between, retraces a bit and then continues towards the west. What is the reason ...
1
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1answer
273 views

Can Mercury hit Earth or Mars in the next 5 billion years?

Mercury is the most unstable planet of the solar system, with an oscillating orbital eccentricity (between 0 to 0.45). It seems there is a 1% probability in the next 5 billion years Jupiter and ...
4
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1answer
91 views

Are many exoplanets synchronously tidally locked like Mercury?

The only tidally locked planet in the Solar system i Mercury. But it is synchronously tidally locked 3:2, because of the relatively high eccentricity of its orbit, so doesn't turn the same side ...
11
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1answer
272 views

What is the current accepted theory as to why Mercury, despite its size, has a similar density to Earth?

According to the NASA web page overview about Mercury, despite the planet being just a bit larger than our moon, it's density is about 98.4% of Earth's. This high density suggests a comparatively ...