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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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 over ...
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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 ...
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Are the 2 planets in this image Venus and Saturn? And is this a fireball shooting star in top right of picture?
I took this picture with my iPhone on January 23, 2023 @6:01pm CST. I am in West Central Alabama very close to the Tenn-Tom Waterway a few miles from the MS state line. I was facing west-southwest.
I ...
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Everything always looks the same
By now I have used 3 different telescopes and a pair of binoculars and no matter what I try to look at at night, whether it be stars, planets, drones, the moon or whatever, everything looks the same. ...
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Was Theia a planet or an asteroid?
According to an article Theia (from the Giant impact hypothesis) was an asteroid and according to The Wikipedia article about Theia Theia was an Earth trojan (which is an asteroid). Which is dubious, ...
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Is Uranus the farthest object in Solar System that you can see with naked eyes?
The following text is from this article:
The fact is, even at its brightest, Uranus is still quite faint. It’s barely perceptible as a dim speck of light to the unaided eye, even under dark skies. At ...
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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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Do planets affect their stars beyond causing them to wobble?
Are there any situations in which the existence of a planet measurably affects its star, aside from orbital wobble? I am curious about possible ongoing affects, not stuff that happened during stellar ...
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How would solar and lunar eclipses differ if the moon was replaced by every planet in our solar system?
A solar eclipse on Earth lasts only around 7 minutes and some of them can be total, annular, partial, or hybrid. The moon's shadow on earth is small compared to the Earth's shadow on the moon. Usually,...
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What is the likelyhood that planet X is a glass (not a typo for gas) planet? What would it mean if it were for what we know of astronomy?
Scientists have been looking for an explanation for the unusual orbits of extreme trans-neptunian objects. One of the possible explanations some astrophysicists have come up with was the possibility ...
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How diverse are chemical reactions outside Earth?
Chemical reactions we are used to here on Earth are hardly possible in most of interstellar space due to extremely low temperature and density (though some pretty complex molecules are found there, ...
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What is the minimum strength of a magnetosphere needed to sustain life?
On Earth, the magnetic field intensity is roughly between 25,000 - 65,000 nT. Assume for a second that we have a planet with double the atmospheric thickness of Earth but with a similar composition. ...
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Stars being eclipsed by planets
I would like to figure out if any of the solar system planets have ever eclipsed a particular star (i.e. crossed the line of sight from Earth to the star) or will eclipse it in the future. Is that ...
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Tables or software for some astronomical data
Recently I saw a beautiful (but not rare) phenomenon - Jupiter was "directly above" the Moon, that is, they had the same azimuth and a small difference in altitude.
I would like to see on ...
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Does the orbital velocity of a planet affect its escape velocity from the planet surfaces?
I'm trying to write a hard sci-fi novel with good accuracy, but when it comes to astronomy, I'm a total amateur.
Here's my fictional planet that orbit a black hole information:
Star Mass = 10000 Solar ...
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Is it possible for us to have mistaken a few brown dwarfs and a few white dwarfs for a burning ethane-octane-oxygen planet?
Is it possible that we humans may have missclassified a handful few but not all brown dwarf stars or white dwarfs, when there really could be possibly a burning planet? Assuming a large enough planet ...
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If a planet orbits an M-Star in an S-type orbit around a G star, what is the minimum distance from the G star that it could remain tidally locked?
I'm wondering how close a planet-M-dwarf system could orbit a G star and have the planet remain tidally locked to the M star. I'm curious, because I'm designing a habitable planet, and I want 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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Could a planet have a massive crater without collapsing due to gravity / other factors?
A severely destroyed planet is a popular trope in media. Here are a few examples from fiction with pictures (spoiler warning).
A crater with a diameter 1/3rd the size of the planet itself:
Earth (...
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In which Indian Institutions can I find Planetary Scientists or Planetary Geologists? [closed]
Which institutions in India provide labs and facilities for research in the field of Planetary Sciences/Planetary Geology?
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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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How would you calculate the "day" on a planet orbiting a red dwarf that is a companion to a larger star?
So the idea is you have an Earth-sized planet with a moon orbiting an M-class star (let's give it .25 solar masses) at 0.2 AU, with an orbital period of 63 days and a 24-hour day. Its orbit has an ...
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What parameters can we obtain from imagery of planets?
Looking at images for the planets of the solar system in all different wavelengths, I was wondering whether we can deduce any information about the planet itself without using anything other than an ...
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How long would it take for a planet captured by a red dwarf to become tidally-locked if it started out rotating retrograde?
So say for the sake of argument that we have a red dwarf orbiting a G of K-class star. An Earth-sized planet forms, maybe at one of the dwarf star's Lagrange points to its primary, and eventually ...
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Does a more massive main proto-body result in more massive satellites? More satellites?
Suppose that we have a forming protostar and an accompanying protoplanetary disk.
Does the mass of the protostar have any direct relation to the masses of resulting planets or amount of resulting ...
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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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