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Questions tagged [asteroids]

This is a tag for asteroids, not dwarf planets or any other astronomical object.

Asteroids are minor planets (especially those in the inner solar system). The larger asteroids can be called planetoids. The term asteroid has been applied to any astronomical object orbiting the Sun that did not show the disc of a planet or the characteristics of an active comet. There are millions of asteroids, many thought to be shattered pieces of rock left over from collisions, the formation of our solar system, and planetesimals (bodies within the young Sun's solar nebula that never grew large enough to become planets). Some asteroids can be captured by a planet's gravity and become moons, such as Phobos and Deimos did for Mars. Below are a few pictures of asteroids.

asteroid

asteroid belt

phobos and deimos

There is more information about asteroids here.

108 questions
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What is the average distance between objects in our asteroid belt?

We've all seen sci-fi movies with asteroid belts that require "great skill" to fly through, but how dense is the asteroid belt really? How much of the belt could you see from the surface of a given asteroid? Is it uneven, with dense and sparse…
Suni
30
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4 answers

Why are there no asteroids or meteoroids with relativistic speeds?

Cosmic rays can have energies going into the $10^{20}$ eV domain. Asteroids and meteoroids originating in the solar system are probably limited in their speed because they all started out from the same lump of matter having more or less the same…
yippy_yay
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What is the speed of the fastest moving body in our solar system?

On Wikipedia I saw that the average orbital speed of planet Earth around the Sun is a whopping $29 783\text{ m/s}$, and it made me wonder are there bodies (planets, meteorites, asteroids) that move faster? My question is not about small photons or…
Willemien
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2 answers

Why would the lack of air in a mine in an asteroid prevent you from flooding it?

In Isaac Asimov's I, Robot novel, two scientists stationed in an asteroid where mining activities are performed say "We could flood the mines, if this weren't an airless asteroid" when considering possible emergencies they could deliberately…
user3723667
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5 answers

How do the terms comet, asteroid, meteoroid, meteor and meteorite differ?

These terms are frequently used interchangeably by the uninitiated to mean approximately a “space rock”. In practical terms, how do their meanings differ?
YUASK
16
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2 answers

How does the central peak in moon craters form?

The central peak in many of the moon's large craters are visible with a telescope and they seem a little odd to me. Can someone explain how they form.
Christopher
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14
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3 answers

Could an asteroid land slowly on Earth's surface?

The concept in my mind is that an asteroid is on a vector similar to Earth's, but slightly slower (e.g., 50kmh slower). As Earth passes it, it enters the atmosphere at a sharp angle, and since Earth was passing it, it just barely touches down due to…
orokusaki
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4 answers

Why did NASA need to observationally confirm whether DART successfully redirected Dimorphos?

NASA's DART impactor made a head-on collision with the asteroid Dimorphos on September 26, 2022. A real-time video feed gave immediate confirmation of the direct hit. But according to this press release, NASA had to observe Dimorphos for two more…
tparker
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13
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7 answers

What is the current status of Pluto?

Pluto has been designated a planet in our solar system for years (ever since it was discovered in the last century), but in 2006 it was demoted. What caused this decision? And is there a chance that it could be reversed? Edit: well,…
peSHIr
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12
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3 answers

Why did the asteroid belt between Mars and Jupiter form as it did?

I'm curious about why the asteroid belt wasn't pulled by Mars's or Jupiter's gravity or formed into either moons or planets. Why did it form into an asteroid belt instead?
Annika Peterson
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4 answers

Minimum size of an asteroid to actually impact earth

From what I understand, an object entering the atmosphere will start to burn up from the tremendous resistance of the atmosphere. Presumably, for asteroids under a certain size, they will burn up completely and never impact the surface of the…
Todd R
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5 answers

What are the chances that a deadly asteroid will hit Earth in the next decade?

What are the chances that an asteroid that will kill multiple people will hit Earth in the next decade?
Christian
8
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1 answer

Are there any models for distribution of asteroid sizes in a belt?

Question: Is there any function that can describe the distribution* of asteroid diameters expected within an*' asteroid belt? *: distribution as frequency of occurrence within the asteroid belt or absolute numbers, not as positional distribution or…
Oxy
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Are there Trojan family or Hilda family satellites locked in Earth's orbit?

Jupiter has many Trojan asteroids located at Lagrangian points L4 and L5 and Hilda asteroids dispersed between points L3, L4, and L5. Does the Earth have similar satellites? If so, how many?
oosterwal
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Is the Apophis asteroid a concern?

I was watching the TED lecture How to defend Earth from asteroids , and the speaker Phil Plait spoke of the possibility of this asteroid hitting Earth. He also said something about a Mayan legend. He says it's not a concern, is there a consensus on…
YUASK
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