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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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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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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If you were standing on a habitable moon of a gas giant, what would the planet look like during the day vs the night? [closed]
If you were standing on the proplanetary side of a habitable moon of a gas giant, and the moon had a thick enough atmosphere to make the sky blue, how would the gas giant look during the day? Would it ...
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What is the maximum size for a solid celestial body such that it still can be tunneled down to the core?
Old science fiction had lots of stories that involved people exploring the center of Earth, like for example Journey to the Center of the Earth, by Jules Verne. As Earth sciences advanced, this sort ...
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Are gas planets in hydrostatic equilibrium?
Why don't gas planets get bigger and smaller over time? Are their sizes constant? Are they in hydrostatic equilibrium like the Sun? Is there an internal force against gravity that does not allow ...
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Have there been any searches for extraterrestrial life which doesn't require water, oxygen and carbon?
This is question is similar to this, but that question has already been voted to be closed. I will add though that I joined this website today, so I am still learning how to write a good question here....
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Life forms on planets not requiring water and oxygen as basic building blocks [closed]
When scientists explore other planets such as Mars, they look for life derived from water and oxygen (correct me if I am wrong) with a purpose to see whether that planet is habitable for humans or not....
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Which world did Carl Sagan know of with a million moons?
I recently read Carl Sagan's The Cosmic Connection. In it, he begins the seventh chapter with a series of claims to depict the universe as "vast and awesome."
I'm particularly interested in ...
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What kinds of stars have viable habitable zones other than G-type stars, and what would life be like orbiting them? [closed]
What would foliage, landscape, and quality of life on dwarf stars and blue stars? Would it be possible for a human to live without high-tech devices and such?
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Binoculars 10x50 in light polluted place
I think to buy cheap 10x50 binoculars for astronomy observations. My leaving area is light polluted, I can see only bright stars and planets in naked eye.
Will I can with this binoculars observe ...
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Planets looks like normal stars when I see them using telescope
I've been trying to see planets using my 114 mm (aperture) f=900 mm telescope. For the moon, I got very good quality pictures, but when I try to see planets they just appear to be as if I'm looking at ...
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Would an accumulation of dust in a planet's L1 Lagrange point plausibly obscure it from Earth?
I'm designing a hypothetical newly discovered planet in our solar system that has an ecosystem comparable to Earth's that supports intelligent life. The explanation given for the planet remaining ...
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Is there a Lagrange point between the earth and the moon?
Is there a Lagrange point between the earth and moon where a space station could sit forever without orbiting around either? Just curious, but it seems like a place like that would be perfect for ...
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What are the time periods of precession of equinoxes of other planets?
Earth has a time period of 26000 years approximately for precession of its equinoxes.
What are the time periods of precession of equinoxes of other planets?
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Why do most dwarf planets have mass comparable to moon?
It was quite interesting to spot that most dwarf planets have masses close to that of our moon (if we let an error to fluctuate within two orders of magnitude).
Why it is so? Is there any common ...
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If the Earth became tidally locked with the moon, would that last forever?
If the Earth and the moon became tidally locked, would this last theoretically forever (assuming no external gravitational force modifies their orbits, for example, ignoring the effects caused by the ...
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How am I supposed to locate the planets Uranus and Neptune with a 70 mm f/5.7 refractor?
I can locate all of the planets other than Uranus and Neptune. This is mainly because they are very dim and I live where there is just enough light pollution so that I can't spot them. I have a Gysker ...
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Why aren't there sulfuric acid seas on Venus?
It's commonly known that sulfuric acid rain doesn't reach Venus' surface. It evaporates instead because the surface it too hot.
But considering how high the pressure at the surface (9.3 MPa), shouldn'...
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Could a magnetosphere be created for Venus by recreated by spinning-up the planet to a 24 hour day?
If Venus in it is current state, started rotating at the same rate as Earths 24hrs rotation, would it develop a magnetic field of roughly the same strength as Earth's?
If so, would that help in any ...
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If planets are ellipsoids why don't we have 3 diameters?
We know that each ellipsoid has 3 diameters named $2a$, $2b$, and $2c$.
The Earth and all planets, in general, are ellipsoids (Saturn is the best example because it's the most oblate planet in the ...
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How do rocky planet break up? Would they fragment into "a gazillion" rocky pieces pieces, or crack open like an egg?
I remember seeing Star Wars, where Darth Vader shoots a superb laser (Death Star) to obliterate a populated planet, Alderaan (how inhumane).
The problem is, the planet cracked into a gazillion rocky ...
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Daylight hours on Titan?
I still cannot seem to wrap my head around Titan's day and night based off of math. From what I understand, Titan has a day of 16 earth days (384 hours) in which it circles Saturn once (its day and ...
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Accurate formula for calculating the mass of an exoplanet using the transit method
A friend and I did some work on exoplanets with the help of a research institute (IEEC in Spain) for a major high school project. What we did was to "redetect" the exoplanet XO-6b through ...
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Planet's distance data from JPL Horizons - Mars Curiosity mission
I am looking for distance measurement in AU between planets and Earth.
E.g. For Mars, Current distance, or distance of Mars from Earth at any given datetime, along with minimum (closest approach), ...
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Can a destroyed earth reform into another habitable planet?
Let's say a planet-sized object collide with earth, disintegrate it, then reform at the same orbit as earth. Will it eventually formed into a habitable, life-supporting planet with living organism?
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What would the temperature be on the surface of Sirius B [closed]
If Sirius B was a planet like Earth and not a white dwarf star what would the temperature be on the surface of Sirius B at its nearest and furthest distance? 8.2 AU to 31.5 AU
EDIT: I want to know if ...
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Is it possible that Planet 9 was thrown out of the Solar System? [duplicate]
Is it possible that this planet changed other planet orbits (from which we assume that it exists) but then was thrown out of the Solar System in past when Sun was close to some other star? And it ...
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Earth-Mars-Moon or No Moon Barycenter Orbit Possible?
Could an object of sufficient mass deflect Mars so that it ends up stably orbiting an Earth-Mars-Moon barycenter? What would the distances eventually become between each orbiting body?
What if the ...
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What value of density would a planet need to be classified as a mini-Neptune?
EDIT: well, now I have more
For reference:
A terrestrial planet is a planet that is made out of silicates and metals.
A Mini-Neptune is, as far as I know, the smallest type of giant planet (arguably,...
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What is precision of planet periods data?
Wikipedia gives $10759.22$ days for sidereal period of Saturn. I have calculated a period from de441_part-1.bsp and obtained $10736.247\bar{2}$ days. Why such a big difference? Which is more accurate? ...
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If Planet 9 is a primordial black hole with a mass of 5 Earth, is it possible to detect it in a ground telescope? What should we seek in this case? [duplicate]
If planet 9 is not a planet but a black hole how can we find it? Can we see gravitational lense or infrared/gamma light?
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How long would it take to realize there are "star-like objects" (i.e. planets) that change position in respect to the "fixed stars"?
If you were using unaided observations and were unfamiliar with astronomy (and maybe just pen and paper for recording anything), how long should it take to notice that Mercury, Venus, Mars, Jupiter ...
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Best lens for a beginner
Just bought a Celestron StarSense Explorer DX 130AZ for my son. What is the best lens to use for viewing planets? What are some easy tips for him, to help explorer his passion? He has the 25mm and ...
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When might Rowan-Robinson's planet be discovered or disproved?
A month ago Michael Rowan-Robinson discovered three dots on old images of the sky which may or may not be an undiscovered planet (that's not identical to Brown's and Batigyn's hypothetical planet). I ...
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Could stars like S2 near the galaxy's center have planets in a stable orbit?
I read about one of the stars orbiting Sagittarius A* and according to Wikipedia, it reaches a maximum speed of 0.03c during its orbit. Would this (or any other factor) make it impossible for a planet ...
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Was the young Sun cooler or hotter than it is today?
Generally, astrophysicists say that the young Sun was only about 70% as warm as today, which leads to the alleged 'Faint young Sun paradox' about how a young Earth could have been as warm as it (again,...
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At what rate does the right ascension and declination of a planet, the sun and moon change per hour?
I'm currently building a web app and am getting the RA's and Dec's of solar system objects based on date and time chosen by the user. Then using the gmst for 0 hours of the date, the app calculates ...
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