Questions tagged [solar-system]
Questions regarding the Sun and objects orbiting it.
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How certain is the Sun's classification?
Curious Question here.
How do we know the Sun is a G-Type Star?
Our sun (Classed as G2V) apparently lies around the 5,780 Kelvin. Yet NASA generalizes it as 6,000 K- and is apparently white even ...
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Do the inner-Earth planets actually align with the constellations we see?
For example, because the Sun is the center of the solar system; when we think that the Sun is on the constellation of Aries, in actuality, isn't Earth lining up with the constellation opposite Aries: ...
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Outer Limit of Oort Cloud
In most popular astronomy articles I see the Oort Cloud described as having a radius of about two light years. Is there any firm basis for this or is it merely a guess?
If it is that big, and Alpha ...
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Protoplanetary disk luminosity - looking for a sanity check please
I've been told to "consider an Earth-mass of interplanetary grains (roughly spherical with a radius of a few microns) in a protoplanetary disk. Let the particles be in a torus with a cross-...
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Periodic motions that affect earth axis tilt
It is said that the earth axis changes its tilt with a period of 41 000 years. So used the image
https://upload.wikimedia.org/wikipedia/commons/1/17/Obliquity_berger_0_to_1000000.png
removed the grid ...
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Was the recent blue spiral over Hawaii really a SpaceX rocket dumping fuel?
Is the observed phenomenon really consistent with a SpaceX rocket dumping fuel or decelerating or something? I'm skeptical. There are several things to discuss.
The speed of the blue spiral is much ...
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Is the solar system barycenter affecting the Earth weather?
I do not have the numbers but I guess the solar system barycenter should move much more than the Earth radius, and if that is correct then it should not be affecting the Earth's temperature.
I mean, ...
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Orbital decay of the sun's orbit around Sgr A*: is it likely?
What are the possibilities of the sun orbiting the black hole Sagittarius A* at a very close distance? Is there anything that could possibly alter the solar system's orbit, bringing it much closer to ...
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Different results for the same JPL Horizons query
On JPL Horizons website, I'm using the following query to get vector state for Earth:
...
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How to get the right ascension of the Moon?
Is there any approximate way to calculate the right ascension of the Moon? I already got declination but still, need the right ascension to calculate the final position of the moon. Thanks for all ...
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Would the influence of a black hole nearby cause a tilt of 63° of our solar system in relation to our galaxy?
I am trying to understand the influence of black holes and the tilts of solar systems on their axial plane In relation to the plane of their host galaxies.
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Where was the solar system born? Alternatively, how far back in time can we retrodict the location of the solar system?
I have two related questions:
Where in the Milky Way did the solar system form? Is there a particular nebula it can be traced to?
How far back in time can we track the location of the solar system ...
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What is approximate numerical equation of the apsidal precession of the Earth-Moon barycenter?
What is approximate numerical equation of the apsidal precession of the Earth-Moon barycenter? Or is it only constant 11.45 arcsec/year with unchanged accuracy to 0.01 arcsec/year for a million years?...
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Do conjunctions of planets block out the sun and cause measurable cooling of the atmosphere on one of the planets?
Is a significant amount of light energy blocked by one planet such that there is noticeable cooling of the atmosphere of another?
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First time mention of coplanarity between Solar Systems planets
When comparing Galileo, Copernicus and Hypathia models to describe the solar system, each of them agree on coplanarity, based on their representations. Anyways, it was not until Kepler and Newton that ...
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Could we detect the light of cities at night in other solar systems?
Would it be possible to see electric lights on distant planets using current telescopes?
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Is there enough matter orbiting the sun to make a second sun?
I read somewhere a long time ago that there is enough matter in our solar system in the form of rocks and dust to create another sun.Is this correct? Was our solar system trying to create a 2 star ...
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Why is Earth 1/3 the age of the universe?
The Earth is 4.6 billion years old
The universe is 13.8 billion years old.
3 times the age of the Earth
Are there other planets with ages that are close to say 1/4 1/5 etc the age of the universe? Why ...
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Could the newly discovered glow in the solar system be antimatter?
Could the newly discovered glow in the solar system be a sparse cloud of interstellar antimatter slowly annihilating with the solar wind?
The glow I am talking about is discussed at: https://www.nasa....
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Were any other planets in the solar system previously habitable?
Could other planets in the solar system previously have been habitable planets such as Earth but eventually like all things died out and ceased to be viable? Could this account for the many barren ...
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Escape velocity of leaving the solar system vertically and horizontally [duplicate]
Is there a difference in the escape velocity when leaving the solar system?
a) Vertically (out of planetary plane, in a perpendicular direction to it)
b) Horizontally (in the planetary plane)
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Why the Sun is white if it is G2?
I know it's a simple question, but even I progressed in astronomy, I always had this question. So, I know the Sun, in the MK classification system, it's G2: yellow. But I also know the sun, in visible ...
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How could we detect if Venus or mars were being terraformed by aliens? [closed]
If any other body in our solar system was being terraformed by aliens, what would be the ways in which we would detect this?
Initially I thought of Venus or mars but I guess this could extend to any ...
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How many planets can be seen by the naked eye? [closed]
I can see Venus and Mars, what about the others?
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Can it be possible to get ice from other moons?
Could it be possible to send out something similar to a probe to one of the moons in the solar system that most likely have water under the cover of the ice and then bring back tests to Earth to see ...
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What would our Sun look like from other solar systems?
I came across an article that shows how the Sun looks from other planets of our solar system.
Now I am wondering, how does our Sun look from an exoplanet? I am guessing it must be looking like a 'star'...
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What (if any) role did Earth play in the evolution of the solar system?
We all know that Jupiter played a great role in the Solar System by cleaning up debris and dust from the Solar System, and deflecting asteroids. Saturn also played a similar role. Uranus and Neptune ...
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Do planetary hours have any real astronomical basis? [closed]
Planetary hours are an ancient theory that each of the 24*7 hours of the week is "ruled" by a certain celestial object in the solar system. Among other consequences, this theory gave rise to ...
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How to show that a complete revolution of Earth around the sun takes 365 1/4 days?
Seasons change regularly and day and nights also.
The fact that Earth takes 365 1/4 days to complete one complete revolution was found a long way back in history, but so far I can't find any current ...
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Are two definitions of a tropical year inequivalent?
Tropical, or solar year, which is 365.24219 days (a day being 86400 seconds) is defined in two ways (implying that they are equivalent):
Amount of time from vernal equinox to vernal equinox.
Amount ...
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What if the sun was replaced by Alpha Centauri? [closed]
What would happen if the sun suddenly got replaced with the entire Alpha Centauri system? Alpha Cen A will be in the sun’s position, with Alpha Cen B not too far off into the distance. How would this ...
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Tropical or sidereal orbital period when calculation Solar System positions?
I'm reading Practical Astronomy With Your Calculator Or Spreadsheet by Duffett-Smith and Zwart. When calculating the positions (in equatorial coordinates) of the Sun and planets the authors use the ...
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How many undiscovered planets might be in our solar system?
Some people talk about the possibility of a planet 9. Could there be a planet 10 or 11? How many undiscovered planets could there be in our solar system?
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Single axis solar tracker tilt angle calculation
I'm working on single axis solar tracker project. Solar panels will towards the sun with maximum angle from sunrise to sunset. the panel direction is east-west or near east-west. I need to make angle ...
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What are different forces acting on a planet which may be related to axial tilts?
In our solar system, we see that the axis of rotation of planets is tilted forex. The axial tilt of Venus is near 179 degrees. Venus, Uranus, and Pluto have large values of axial tilt(more than 90 ...
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Initial state for a 3-body problem to create Figure 8 [ restricted to 2D ]
I've made an n-body simulation solution using the naive algorithm of O(n^2) in my library ChelseaaJS.
I was trying to make some pleasing 3 Body simulations.
I wanna do the 8 figure thing.
I know it's ...
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Could a planet theoretically have a stable orbit between Venus and Earth OR Earth and Mars
Take a planet, identical to Earth in size, mass, gravity, rotation, etc.(but without the moon). Could this planet theoretically maintain a stable orbit for many hundreds of millions of years orbiting ...
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Are heavy elements equally distributed throughout the Solar System?
I want to know if heavy elements are distributed roughly evenly throughout the Solar System or if they are (excluding the Sun) concentrated mostly in a particular area, such as the inner part. Would ...
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Calculating net gravitational force on Uranus
I want to calculate the net/total gravitational force which is being exerted on the planet Uranus. There are many objects in our solar system like the Sun, other planets, moons of other planets, moons ...
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How scientists find the direction of rotation of planets?
How do we know that Mercury, Earth, Mars, Jupiter, Saturn, and Neptune rotate counterclockwise and Venus, Uranus, and Pluto rotate clockwise? How do scientists determine the direction of rotation of ...
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Besides Luna, are there any models of how moons become spherical and round?
Question
Given the theorized exceptional formation of Luna, (Giant-impact Hyphothesis, Wikipedia), are there any similar animated models of how the other, much smaller, moons in our solar system ...
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absolute magnitude of an asteroid
I've done some research and found that one could derive the absolute magnitude $H$ of an asteroid in the following way. $H$ is the brightness of the asteroid, observed on Earth, if the asteroid were ...
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Does the Sun shift periodically between prograde and retrograde rotation about its axis?
Prograde means rotating in the same direction in which most of the planets in our solar system rotate, which is counterclockwise, and retrograde rotation means the opposite, i.e., clockwise rotation.
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How to calculate absolute magnitude of planets?
Knowing:
Star's radius $r_s$ , luminosity $L_s$, and absolute magnitude $V$
Planet's radius $r_p$ , albedo $a$ , and distance $d_s$
How can you calculate the absolute magnitude of a planet in a ...
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Why do the Sun and gas planets rotate faster at equator than at poles?
From this site, it states that:
The Sun spins faster at its equator than at its poles.
I have also read somewhere that the gas giants (gaseous planets like Jupiter, Saturn, Uranus, and Neptune) also ...
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Does interplanetary magnetic field interact with the planet's own magnetic field?
The Wikipedia states on the page about the Interplanetary magnetic field that
The interplanetary magnetic field (IMF), now more commonly referred to as the heliospheric magnetic field, is the ...
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Why does the axis tilt (obliquity) of Earth change over time?
I have recently learned that the polar axis of Earth moves in a complex fashion. There are both precession and nutation. I have learned that Earth's obliquity varies between 22.1 and 24.5 degrees on a ...
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At which point does the inner solar system end and the outer solar system start [duplicate]
I've heard how the inner solar system ends at the asteroid belt but where in the asteroid belt?The start?The middle?The end?Is there an exact distance that is put in place?
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Does the north pole of the Solar System (with respect to the invariable plane) point towards the galactic center?
How is our Solar System as a whole (not the wobbly Earth) tilted with respect to the invariable plane of the Milky Way?
I understand our Sun's north pole is largely pointing towards our direction of ...
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How it is not possible to say if Titius–Bode law is a "coincidence" or not?
From Wikipedia:
No solid theoretical explanation underlies the Titius–Bode law – but it is possible that, given a combination of orbital resonance and shortage of degrees of freedom, any stable ...
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