Questions tagged [definition]
Questions targeting the exact (possibly mathematical) description of a phenomena or term.
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Do astronomers generally agree that the distinction between comets and asteroids is not so clear?
edit: I just saw this tweet and find it incredibly relevant :)
begin question: See this answer and then consider if there are known or likely solar system bodies that might be identified as both ...
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What exactly is a "moon"?
Recently some new moons of Jupiter were discovered. However the moons are pretty damn small indeed - only a few kilometers wide. That makes me wonder if they should even be called moons in the first ...
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Metallicity of Celestial Objects: Why "Metal = Non-metal"?
Metallicity of objects refers to the amount of chemical elements present in it other than Hydrogen and Helium.
Note: The other elements may or may not be actual ...
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Would an analogue of the definition for planets also work for moons?
This is a follow up question to What exactly is a "moon"? The conclusions I draw from James K's answer is that the IAU should define what a moon is. They haven't done so yet, but they should.
The ...
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What is the definition of a "pole" of a celestial body?
What is the definition of a "pole" of a celestial body?
Earth's pole is defined as it's rotational pole. The North and South Poles are the two points on Earth where its axis of rotation ...
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If Jupiter and Saturn were considered stars, which of their moons would qualify as planets by 'clearing the neighbourhood'?
Jupiter has four and Saturn seven spherical satellites. Jupiter's moon Ganymede and Saturn's Titan are larger than Mercury and they're the most massive moons at 0.0248 M♁ (Ganymede) and 0.0225 M♁ (...
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What is the difference between the terms collision and merger? How are they used differently in Astronomy?
We often hear of mergers of two stellar objects but we also sometimes talk about these or much smaller objects like planets or asteroids colliding.
What is the actual differences between Astronomy and ...
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What are Ellerman bombs and how can we identify them?
Have you ever heard about Ellerman bombs? Spaceweather.com talks about them on their news page. You could see some of them around sunspot AR2835:
Ellerman bombs are magnetic explosions about one-...
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Are there actual asteroids in the Oort cloud?
This answer to At what annual rate are new exoplanets being recognized? How does it compare to new asteroids? shows that the rate of new asteroid discovery is roughly two orders of magnitude higher ...
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Should only spherical satellites be considered 'moons'? [closed]
Since Titan and Ganymede fall into the same category as Deimos and Phobos or the components of planetary rings, the category of moons, it's like if all asteroids were considered planets. Tiny ...
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