Questions tagged [mercury]

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

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Are there auroras on Mercury?

Auroras on Earth are caused by interactions between the solar wind and the magnetosphere. I've also seen a few pictures of auroras on Jupiter and Saturn. Mercury has a global magnetic field. Does it ...
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What effects does the motion of the Sun have on the perihelion precession of Mercury?

According to the wikipedia page, there are multiple effects contributing to the perihelion precession of Mercury. Of course, according to this link and this link we know that the Sun is itself ...
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Does the axial tilt of Mercury and Venus vary?

The axial tilt of Mars varies greatly over time, with a tilt varying between 15 and 25° over the last million years, and varying even more over the last 5 million years. The Earth's tilt on the other ...
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Why doesn’t the Sun fill the sky on Mercury?

I’ve seen a lot of photos showing Mercury in front of the Sun when it passes by and you can see just how tiny it is in comparison. Here’s a great example: So I’d expect if I was travelling towards ...
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How could one use the transit of Mercury to try and find the Astronomical Unit?

I am trying to use the transit of Mercury to estimate the distance between the Earth and the Sun, or 1 AU. I know that I need to observe mercury from two antipodes, but I do not understand any of ...
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How was the Messenger spacecraft used to measure Mercury's orbital precession to such accuracy? Could this have been done using radar?

This comment under an answer to Path of Mercury and general relativity mentions that the Messenger spacecraft was used to measure the precession of Mercury's orbit to such accuracy that the tiny ...
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Path of Mercury and general relativity [duplicate]

I have read that many physicists challenge the theory of general relativity, and it has been proved many times that it is correct; my question is on Mercury's orbit. And we know that many of ...
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2answers
188 views

What is wrong with this measurement of the synodic period of Mercury?

I'm measuring the synodic period of Mercury using Stellarium. When measuring the synodic period one needs to choose a reference point to start the measurement, and I choose the point when Mercury is ...
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How to write a normalized, dimensionless form of Binet's relativistic equation?

$$\frac{\delta^2 u}{\delta \theta^2} + u = \frac{\mu}{h^2} + 3 \mu u^2$$ This is Binet's relativistic equation. Here $u = 1/r$ where $r$ is the radial distance, and $\mu$ is the reduced mass of the ...
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How did Arecibo make radar images of ice on Mercury's poles?

update: I still haven't been able to get my hands on the Icarus paper linked below (I'll try other libraries) but these are newer and quite interesting!: Constraining the thickness of polar ice ...
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Where can I find data on Mercury's orbit to fit a model to? [duplicate]

I have a project in which a Monte-Carlo method is used to find the optimal parameters for some model that is fit to a data set. I want to fit a model for the orbit of Mercury using this methods, but I ...
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What could possibly save an atmosphere other than a magnetic field? Why can't a magnetic field save the atmosphere in certain cases?

Similar question here. We know as a fact that the magnetic field protects planets from Solar Wind, a damaging, continuous, atmosphere-stripping wind of charged ions. Thus, a magnetic field protected ...
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Historical Distance of Planets to Earth [duplicate]

I'm curious if there is a readily accessible tool available, or simply a reliable way to find out what the distance of the planets in the solar system were on a given date. For example, if I am ...
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161 views

If Mercury and Venus where to collide would it make a habitable planet? [closed]

I have been wondering for a while now about a scenario of where if you combined Venus & Mercury would it be habitable if located in the goldy locks zone? I have found in my little research that ...
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Explanation of resonance stability and instability

I'm having some trouble grasping the idea of planetary resonances due to what seems to me like an ambiguity. It is known that the asteroid main belt is sculpted by the Kirkwood gaps, corresponding to ...
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Can Mercury's core “boil over” if it gets to close to the Sun?

I was reading about how Mercury's core makes up most of the volume of the planet. I'm guessing this is both because of the small size and the distance to the Sun. If Mercury got too hot could it ...
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Why does in-the-sky.org say that Mercury is not visible from Taipei these days?

I know that viewing Mercury is a challenge, but I'm fairly close to the equator and Mercury was at greatest elongation just a week ago. In-the-sky.org says: All around the world, Mercury is visible ...
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What is the temperature under the surface of Mercury?

What is the temperature under the surface of Mercury? I know at the surface the temperature varies greatly (-297 F to 801 F). I also realize that the answer would likely depend on depth. Do we know ...
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Mercury mapping attempts before Mariner 10?

Mercury's surface was not mapped up-close until Mariner 10 passed by in 1974. This was followed by MESSENGER in 2008. I have seen several attempts of mapping Mars that came before space exploration, ...
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What is the inclination of Mercury's orbit w.r.t. the Sun's equatorial plane?

What is the inclination of Mercury's orbit w.r.t. the Sun's equatorial plane? Additionally, what is the orientation of Mercury's orbit (long axis) w.r.t. the Milky Way?
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Orbit of Mercury

As observed from the earth, the sun appears to move in an approximate circular orbit. For the motion of another planet like mercury as observed from the earth, would this be true? If not, why? What ...
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How large was Mercury before it shrunk?

There's a theory that the reason Mercury has such an enormous iron core is that it was once a much larger planet before it got impacted by an object, resulting in most of its mass getting blasted away....
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Exactly how elliptical is Mercury's orbit, visually, without exaggeration?

Reposting question from https://www.reddit.com/r/askscience/comments/5e1zhy/what_does_mercurys_orbit_really_look_like/ which reads: First the full question: What does the orbit of Mercury really ...
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Massive degraded impact crater on Mercury - chemical evidence?

The planet Mercury has a myriad of impact features - this has been known for some time. However, observe in the following images, a relatively large 'High-Mg region' detected on the planet (below): ...
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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, ...
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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 ...
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602 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 ...
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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 ...
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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 ...
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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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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 debris won't go far away ...
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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 ...
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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 ...
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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 ...
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239 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 ...
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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?
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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 ...
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281 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 ...
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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 ...
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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) ...
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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?
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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 ...
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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, ...
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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 ...
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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 ...
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Are many exoplanets synchronously tidally locked like Mercury?

The only tidally locked planet in the Solar system is 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 ...
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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 ...