Questions tagged [planet]
Questions on astronomical objects orbiting a star massive enough to be rounded, not massive enough to cause fusion, and which have cleared its orbit of planetesimals.
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Do all the planets in the universe rotate? [duplicate]
Do all the planets in the universe rotate by their own means. Do they rotate like the Earth? Are there any planets which don't rotate?
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Why wasn't the planet Uranus recognized by ancient cultures?
Mercury, Venus, Mars, Jupiter, and Saturn have been identified by ancient astronomers as they are visible with naked eye at night. The planet Uranus, despite being visible during very clear nights, ...
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Timelapse Video Of Motion of Mars?
I'm trying to find a timelapse video of mars moving against a fixed background of stars - could someone point me in the right direction? Thank you!
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How can Jupiter rotate faster at the equator than at the poles (in degrees per second)?
Jupiter rotates slightly faster at the equator. If inertia is conserved as average angular momentum, what is the physical mechanism that creates a gas which is ~1% faster angular momentum at the ...
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How can I calculate current position of planet in sky
How can I calculate current position of planet in sky from earth's point of view. I want to calculate based on given DATETIME and Location
For example, if I see current position of planets on "23 ...
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Is there a noob-friendly website/app for tracking a astronomical body's apparent movement over time?
As I walk home along my road most nights in winter, I see the Moon and one-or-more planets.
Unsurprisingly, over the last 2 months, if it's been the same planet and it (and the Moon) has been in ...
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The rocky planet sizes between the Sun and Jupiter are small, big, bigger, small, and unfinished. Is there a reason?
The rocky planet sizes between the Sun and Jupiter are small (Mercury), big (Venus), bigger (Earth), small (Mars), and unfinished (the asteroid belt). Is this just random chance or is there a theory ...
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calculating apogee and perigee for moon and sun
The perigee does not necessarily happen when we have a full moon, using swevents we can easily determine the moon phases. Now can we use python to determine when ...
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On the relationship between semi-major axis and the Longitude of the Ascending Node
I noticed something looking at the Longitude of the Ascending node of various planets.
Mercury: 48.331°
Venus: 76.680°
Mars: 49.57854°
Jupiter 100.464°
Saturn: 113.665°
Uranus: 74.006°
Neptune: 131....
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What would happen if a low-mass primordial black hole was captured by a brown dwarf or planet mass object?
Prompted by a recent PBS SpaceTime video
The video in question discusses what would happen if a low-mass (asteroid-mass) primordial black hole were captured in the core of a Sun-like star (a so-called ...
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Planetary Conjunctions
Was there a conjunction between Jupiter and Mercury in 2 BC seen from Persian Gulf? Was there a conjunction between Jupiter and Venus in 4 BC seen from the Persian Gulf? If so, what day, time, and ...
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Planets Named After Roman Gods, Except Earth
I’ve looked this up, but not necessarily sure the internet has the right answer. Why are the planets in our solar system named after Roman gods, except Earth, and why is only one of the nine planets ...
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Why is it impossible to infer the surface temperature of Venus by spectroscopy observation from earth?
It is well known that the surface temperature of the sun is determined by fitting the sunlight with the black-body spectrum.
Why is this inappropriate for Venus?
I have the question because of the ...
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Celestial "orbits"
I heard that we're losing our moon, its slipping away from us in such tiny imperceptible steps that we don't notice any significant change even over kiloyears.
The same must apply to planets, inching ...
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Why did the dust between the planets disappear during the birth of the solar system?
I'm catching up on my childhood mistakes. One of them was the "nuclear flash", the enormous explosion when the sun ignited. Apparently, this did not happen as the ignition of the sun was a ...
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Is there a formula for calculating surface temperature of a rocky world based on atmosphere and solar input?
For example, a thicker atmosphere would probably lead to less temperature variation . . . I assume that much is obvious. And, greenhouse gases trap heat.
But when posed with a question like "...
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How is a Planet's Moment of Inertia Measured Remotely?
In the July 2023 issue of Sky & Telescope there is an article titled Sights Set on Uranus. In that article the following statement is made:
Since the 1930's we've suspected that Uranus and ...
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For what period of time can planets be viewed from the North Pole as just being there?
I would like details on observations (since North Pole is not possible, approximately around the North Pole) which tell us for how long are planets visible from the North Pole?
I understand that ...
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How much of the surface of other planets is lit by the sun?
Since the sun is much larger than the earth, it should ideally light up a considerable portion of the earth rather than only half of it.
However the sun lighting only half of the earth can be ...
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Potentials of space mining [closed]
I'm conducting research on the potential benefits of space mining on asteroids, like 16 Psyche. I'm hoping that those who are more knowledgeable than me can help with the following questions:
Are ...
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Difference in results between JPL Horizons and cspice (rust-spice)
I am calculating the apparent planetary position of planets using the cspice library (I am specifically using rust-spice, which is a wrapper of cspice in Rust).
when I calculate the same values in the ...
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Why can't a half-illuminated planet support life at all?
Here is my own translation of the Polish version of the Drake equation article in Wikipedia:
(...) They must provide the right amount of heat. The smaller the star, the less heat it gives off and the ...
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Is the magnetic permeability (mu_0) necessary in the expression for planetary magnetic field?
To numerically analyse the Lorentz effect due to the magnetic field, say, radial component on a charge particles which of the expression would be correct, $\{ B_r = \frac{2R}{r^3} g_1^0 \cos(\theta) \}...
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Why don't scientists believe Earth's surface water came up from the mantle?
I read, periodically, that there is more water trapped in the mantle than there is in the oceans - possibly a lot more.
If so, why don't any geologists believe that Earth's surface and near-surface ...
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When did Venus get as hot as it is now?
My previous question turned out to not ask the question I thought I was asking.
I have read that Venus began its heating-up around 700-750 million years ago.
When did the Venusian atmosphere get ...
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When did Venus reach approximate radiation equilibrium?
I have read that Venus is roughly at radiation equilibrium - that is, heat out is approximately equal to heat in. I have also read that Venus began its heating-up around 700-750 million years ago.
My ...
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Does the Sun have different unique orbits around barycenters?
After reading this question and seeing its image I thought about this question I'm going to publish.
Does the Sun have different unique orbits around the barycenter for its multiple planets?
If yes, ...
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How common for all 7 planets to be above the horizon?
I was planning for the Solar Eclipse in April 8th 2024 and noticed that at the time of totality at my location in Western NY, all 7 planets will be above the horizon. Earlier in the day it's all of ...
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Is Proxima Centauri a Planet?
Proxima Centauri meets all the requirements for Planet status, although it is a star, can an object be a star and a planet at the same time? normally, the answer should be no, but this is the problem ...
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Can rings last around planets indefinitely?
Apparently, Saturn is losing its rings (https://weather.com/en-IN/india/space/news/2023-05-04-saturn-is-losing-its-rings-webb-may-tell-us-how-long-they-have-left) However, is there any way or ...
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What is the most common method that a scientist uses to study the cyclones in the universe?
Cyclones have been observed throughout the universe as seen in the following examples:
Jupiter's Great Red Spot is perhaps the most well-known cyclone in our solar system. It is a giant storm that ...
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Planets revolving counter clockwise around the Sun
Planets revolving around the Sun
Hypothetical case:
What could have been or no impact if the planets viz Earth, Jupiter, Saturn, Mercury, Venus, Mars, Pluto, Uranus, Neptune in different orbits ...
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How is a planet (or star's) radius defined?
The radius of a rocky planet like earth is fairly easy to define based on the fact that the ocean's surface is fairly smooth, and it is a natural point to measure. Other planets like Mars, the surface ...
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Are there such circumbinary planet configurations that two suns move towards each other by the sky?
Is it possible that suns move towards each other (not necessarily in opposite directions)? Such a configuration would cause interesting dusk and midday light cycles, in my opinion.
Basically the ...
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Can a star with a stellar mass of 1.176 with a similar composition to the Sun have a planet with these characteristics?
Imagine a solar system similar to ours that has a star with a similar composition to the Sun and a stellar mass of 1.176 and an Earthlike planet with about 1.18 times the mass of Earth in its ...
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What stellar conditions and orbital distance are needed to produce a year length of 515 Earth days and 9 Earth hours on an Earthlike planet?
A planet has a year length of 515 Earth days and 9 Earth hours. It is the same size and has the same climate as Earth. What stellar conditions would be needed to produce this and what orbital distance ...
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Can one or more moons orbit around a double planet system?
Given a double planet system where the two bodies are of similar mass;
Can a moon orbit one or both planets in a stable orbit?
How about an artificial satellite?
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Why do the radii of the outer planets' epicycles have to be aligned with the earth-sun radius in the Ptolemaic model?
I read that in the Ptolemaic model (or the geocentric system), for the retrogade motion to occur at opposition, the radii of the outer planets' epicycles have to be aligned with the earth-sun radius. ...
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why does earth have speed?
I understand that Earth has a quite big speed such as it ends up around the orbit. The sun can't really attract it till the end due to Earth's speed and earth really can't escape due to gravity, hence,...
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Have we observed other habitable planets like Earth? [duplicate]
Have we observed other planets within the “Goldilocks Zone” of a star to have reasonable temperatures, that have a breathable atmosphere, water, and gravity within a healthy range for human life? ...
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Planet and star rotation through gas in the galaxy
If 10% of the galaxy is filled with gasses, and stars contribute to only 1%–2% of the total matter, then shouldn't the gas create friction for the movement of stars around the galactic center and also ...
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How does carbon end up in the remnants
We know that one way carbon ends up in the interstellar medium which by the way is one or the heavy elements that help form the planet.
But we also know that in the core, carbons fuse with another ...
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How small stars help with planet formation
As I understood, low mass stars in their core go through fusion, but only the fusion of hydrogen happens. When it depletes hydrogen, fusion stops as temperature is still not high enough to support ...
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What do chthonian planets look like?
Obviously, a chthonian is going to be hot, but what colours could it have? What would the surface composition be? Would it keep patterns from the gas-bands it used to have, or would those have been ...
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Trouble seeing Mars and Venus more than specks of light
Finally been breaking out the telescope to get a better look at things recently, and have been attempting to take advantage of Mars's and Venus's positions in the sky, but I haven't been able to see ...
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Formation of a non-Sol Oort cloud with high mass planets
Based on recent developments in astronomy, pertaining to a greater degree of measurement, the mass of the Oort cloud around Sol is apparently only about 1.5 times the mass of earth, in contrast to ...
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Could it be possible to detect planets from stars that went supernova through the resulting nebula shape?
It ocurred me, if a star with at least one planetary companion undergoes a nova or supernova, we shoud expect the debris to be deflected to some degree, on exit. To ilustrate it, first let's take the ...
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What is the maximum radius of a pure iron-56 planet?
Suppose we are building a pure iron-56 planet atom by atom, how large can it get in terms of radius before it collapses into a black hole?
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Why doesn't the IAU definition of "Planet" disqualify Mercury and Venus as planets?
Here's the IAU definition of a planet (source):
A celestial body that (a) is in orbit around the Sun, (b) has
sufficient mass for its self-gravity to overcome rigid body forces so
that it assumes a ...