Questions tagged [asteroids]
Questions regarding relatively small rocky bodies in an orbit around the Sun.
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Could the dinosaurs have seen the asteroid that killed them?
Wikipedia says the Chicxulub impactor is thought to have been a 10-15 km diameter object. Would it have been visible to a (human*) naked eye before impact? And if so, would it have appeared like a ...
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How early could we detect an asteroid the size of the one that caused the extinction of the dinosaurs?
Would we know months, years ahead? How sophisticated is our technology's ability to detect it at 100% accuracy?
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Why did they decide to hit Dimorphos in the retrograde direction rather than prograde; was it a "coin-toss" or were there implications for observing?
CNN Space and Defense Correspondent Kristin Fisher does a really good job of summarizing the current state of the Double Asteroid Redirection Test early observational results for general public ...
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Does anything orbit the Sun faster than Mercury?
Mercury's orbital period around the Sun is about 88 days. Comets and other things have gotten closer to the Sun than Mercury does. But has there ever been an asteroid or some other body discovered ...
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What would an asteroid inside of Mercury's orbit be called?
The first Vatira asteroid has been discovered. This makes me wonder if there is already a name for the hypothetical class of asteroids that orbit entirely inside of Mercury's orbit. It wouldn't be the ...
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Why was there a gap in the number of asteroid detections between 1807 and 1845?
The first asteroid, Ceres, was discovered in 1801, although it wasn't called an asteroid yet. Pallas, Juno and Vesta were discovered shortly after. Then no new asteroids were discovered for 38 years, ...
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Why did the distribution of asteroids discovered in 2010 have a radial modulation?
This answer links to one of Scott Manley's excellent asteroid videos Asteroid Discovery - 1970-2015 - 8K resolution. The animation highlights the positions of the meteors at the moment of their ...
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Why are asteroids with zero orbital inclination rare?
This is a plot of orbital inclination ($i_p$) vs. semi-major axis ($a_p$) of 96944 asteroids in the Main Belt, done by Piotr Deuar.
Some structure can be seen in this diagram; clumps are asteroidal ...
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Whats the probability of a hazardous impact for human life on Mars?
Yesterday my sister and I have discussed the recent efforts of SpaceX to create a permanent colony on mars.
When coming to the several dangers of creating a habitat on a different planet, we got ...
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Where on Earth could dinosaurs feel the impact of their extinction asteroid?
Did the possible Chicxulub asteroid impact around 66 million years ago that made the dinosaurs and many other species extinct, cause the Earth to wobble? How large was the area, where they could "...
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How is asteroidal rock formed?
So when planets form, dust from the protoplanetary nebula gets collected by gravity and then heated and reformed under pressure until it forms dense masses of stuff which we call rock.
However, ...
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Why haven't Earth and Venus got any tiny moons? Or have they?
Why haven't some meteoroids gotten caught in Earth's or Venus' orbit?
AFAIK most meteors are tiny fragments from comets. Shouldn't some comet tail sometime have passed Earth orbit at velocities ...
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Have we ever observed a body, such as a large asteroid, "hitting" the Sun?
Some other SE questions about launching ICBM's into the sun got me wondering whether we have ever observed an object on a path that intersected with the Sun? How close did it get?
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What is the difference between asteroids, comets and meteors?
Some celestial objects seem to be referred to as asteroids, some as comets, and some as meteors or meteorites.
What is the distinction between all of these different objects? Are any of them the same?...
user96
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Is it possible that the Rosetta orbiter moved the comet when it crashed?
Rosetta Comet Orbiter (RCO) crashed into the surface of a comet after the comet passed near Jupiter, which would be out-of-range for its antenna to communicate with Earth. So, the ESA made the ...
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Has anyone back-calculated previous close encounters between the Apophis asteroid and Earth?
The Apophis asteroid was only discovered in 2004, and shares an orbit similar to Earth's orbit, leading to many close encounters on the scale of decades.
Most of the stories about this asteroid are ...
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What caused this mysterious stellar occultation on July 10, 2017 from something ~100 km away from 486958 Arrokoth?
In 2017 a series of stellar occultations by asteroid 2014 MU69 "Ultima Thule" now officially named 486958 Arrokoth were timed in order to obtain better orbital information before the New ...
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What's the reason for the hollow region in Oort cloud?
Can someone please tell what caused the hollow space (pointed by yellow arrow) in the Oort Cloud?
I understand that it is called cloud because the cluster of objects does not align with the major ...
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What are Trojan Asteroids and where are they located?
Asides from the main Asteroid Belt, there are Trojan Asteroids - what are these and where are they located?
user8
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How did asteroid (7482) 1994 PC1 get its "face"? Is it reconstructed from optical or radar imaging, or something else?
(Image sources linked below)
NPR's March 10, 2023 Newly found asteroid has a 'very small chance' of hitting Earth, NASA says includes an image of what looks like a computer reconstructed 3D surface of ...
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What is the difference between the Yarkovsky effect and YORP effect?
As far as I understand, both the Yarkovsky effect and the Yarkovsky–O'Keefe–Radzievskii–Paddack (YORP) effect exert forces upon bodies as a result of thermal photon radiation. How do both effects ...
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Is the Apophis asteroid a concern for planet Earth?
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. Is this really a concern?
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Why are asteroids so much richer in precious metals than Earth's crust?
Did the majority of Earth's precious metals sink below the crust during Earth's formation?
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What are the benefits of collecting asteroid samples in situ rather than just waiting for bits of asteroids to fall as meteorites?
Hayabusa and Hayabusa2 are sample return missions from asteroids. But little bits of asteroids fall to Earth all the time as meteorites. Why can't we just study those? What are the advantages of going ...
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Do comets contain any significant amounts of iridium?
I have Googled "iridium content of comets" and can't find anything that suggests comets contain iridium in any detectable quantities. Yet, whenever I read an article about the Chicxulub impactor, the ...
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How loud was the asteroid that killed the dinosaurs?
Asteroid impacts on the Earth can be very loud when they break up in the atmosphere, like Chelyabinsk, captured in this video:
The Chelyabinsk asteroid break-up was ...
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Will Asteroid (2021 LD6) be visible to the naked eye?
There's a lot of hoopla online about asteroid 2021 LD6's close approach to Earth. Will be close enough and large enough to be seen with the naked eye?
PS: More on the object: MPC or JPL
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If the Earth had another moon would it be better protected from asteroids?
Would the moons get struck by asteroids instead of the Earth or would the moons attract more asteroids and make it more likely the planet gets hit?
user52681
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Why do planets tend to rotate in the same direction although they have formed from tumbling asteroids?
The axial tilts of asteroids seem to vary randomly (let me know if this premise is wrong), while the planets have a strong tendency to rotate in the same way. If planets were formed by colliding ...
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Why was this asteroid (4864 Nimoy) chosen to be named after Leonard Nimoy?
The asteroid 4864 Nimoy was recently named after Leonard Nimoy. It was discovered on September 2, 1988 so it went nearly 27 years without a name. Why was this asteroid chosen to be named after him? ...
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How can astronomers determine the difference between "hydrostatic equilibrium" and "just happens to be spherical"?
This is relevant for the definition of a dwarf planet.
I presume the answer will be, well, if we can tell the mass of the body and guess the material. I don't find this very satisfactory because (1)...
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Can earth grazers skip on the atmosphere more than once?
Earth grazing fireballs are asteroids that enter the atmosphere at a low angle, and skip off it, leaving to space again. Would it be possible that they skip more than once and still leave the ...
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Do asteroids have a gravitational field?
I know that asteroids are huge chunks of rock, orbiting a solar system. Do asteroids have a gravitational field and do they gravitationally attract each other to form planets?
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Opportunities to see a near earth object via unaided eyes or binoculars?
I would like to see a near earth object proper with my eyes or binoculars someday.
Has this been possible recently? Are there any upcoming potential opportunities to do so in say the next 20 or 50 ...
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Could this estimate of the size and mass of the Chicxulub Impactor be accurate?
My understanding has always been that the Chicxulub Impactor was in all likelihood an asteroid with a diameter of about 8 - 12 km, but then, the other day, I came across this paper. In it, they say ...
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Could asteroid 'Oumuamua actually be round?
News articles have mentioned that the recently discovered asteroid 'Oumuamua is theorized to be greatly elongated based on observations of brightness variation. However, this hypothesis seems to be ...
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How was Earth's "quasi-satellite" 2016 HO3 "first spotted" and it's orbit determined?
Under a question I asked a few days ago Have there been any documented mini-moons since 2006 RH120? @Hobbes mentioned the recent news about 2016 HO3 - a near-Earth asteroid that stays near Earth ...
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Why haven't more captured small moons been found?
Shouldn't captured moons have the same size distribution as asteroids? And asteroids are more common the smaller size they are. Moons are likely captured if they are in highly inclined orbits, and ...
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What is the composition of an asteroid in percentages?
I am developing a RPG game (or so I like to tell myself) within outer space. Within the game, players would be able to mine small asteroids and collect resources, in order to make money. I'm having ...
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How well would the Moon protect the Earth from an Asteroid?
Would the Earth fare better if the Moon blocked the meteor, comet, rogue planet, or otherwise rather than a direct impact? At what point would the Moon's debris would be an extinction event?
The ...
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How many iridium layers do we know, besides the K-Pg one (the dinosaur killer "smoking gun")?
The hypothesis of a large asteroid impact playing a role in dinosaurs extinction was strengthened by the discovery of a global iridium anomaly in the geologic record, at the Cretaceous–Paleogene (K-Pg)...
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What is a dead comet?
How is a Dead Comet different from the normal comet?
How are they formed?
And why is the Halloween asteroid 2015 TB145 called a dead comet?.
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If an Asteroid was to strike the Earth, would it affect the Earth's rotation?
If an Asteroid was to strike the Earth, would it affect noticeably the Earth's rotation, and if so, how large would this Asteroid have to be?
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Detecting Deep Impact
There have been several accounts in media articles of asteroid near misses, many describe that the asteroid was not seen before the near miss.
After reading the question and answer to How can we tell ...
user2449
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Is this object an asteroid or comet, and how can it produce so many tails?
The NASA Hubble Space Telescope Science Release HEIC 1320 - When is a Comet not a Comet? - Hubble astronomers observe bizarre six-tailed asteroid is self-explanatory, but it doesn't explain what ...
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Comet Neowise c2020 f3 will return in ~6800 years, how can we be sure Earth will be in the right place to see it then?
I have read in several places that the orbital period of comet Neowise c2020 F3 is about 6800 years. In several popular media sources it is said that we will be able to see the same comet after ~6800 ...
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Gravitational Properties of Asteroids
How large would an asteroid have to be in order to hold a person so that the person could not escape?
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Did the temporary asteroid name DA₄₂ arise naturally and fortuitously (as a precursor to a Douglas Adams namesake)? Or did someone help it along?
42 (Number) just might be the longest Wikipedia page for a single number integer.
In the Astronomy subsection of that article it says:
In January 2004, asteroid 2001 DA42 was given the permanent name ...
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Orbits of Trojan Asteroids
I understand that the Trojan points are located 60 degrees ahead and behind a planet in its orbit. However, since there are quite a number of Trojans in Jupiter's orbit, they cannot all be exactly at ...
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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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