Questions tagged [asteroids]
Questions regarding relatively small rocky bodies in an orbit around the Sun.
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Why does the background noise in this image of 2020 QG look like corduroy?
The news item Small asteroid becomes closest ever seen passing Earth: NASA contains a "handout image" with the caption:
This NASA/JPL/ZTF/Caltech Optical Observatories handout image ...
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What do we know about the relation of shape to size in asteroids?
Have enough good measurements been made of small asteroids to gather interesting statistics about roundness? Perhaps a scatter chart of each body's greatest and least diameter?
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What is the difference between a depleted comet and an asteroid?
When a periodic comet flies by the Sun enough times, it can become depleted of its volatile elements. Once it is depleted, what distinguishes it from an asteroid, other than records of past sightings ...
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Origins of meteorites?
I am aware that the vast majority of meteorites come from the asteroid belt (including 4 Vesta), with some from the Moon and Mars. Are there any other locations from which meteorites have originated (...
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Are we less safe now that Arecibo is down?
The NASA News item Arecibo Observatory Returns from Tropical Storm Isaias Lockdown to Track Asteroid for NASA begins:
The National Science Foundation facility, managed by the University of Central ...
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Would They Tell Us If An Unstoppable Threat Was Approaching [closed]
This recent piece somewhat kindled my thoughts on this question, but I've pondered it for a while now: https://www.scientificamerican.com/article/a-movie-of-the-evolving-universe-is-potentially-scary/
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How quickly can a ring system be made?
I've seen elsewhere that if a terrestrial planet had a ring system, it would be very difficult (if not impossible) for life to evolve due to the shadow the rings would cast on the temperate zone in ...
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Closest stable orbit about the sun of an asteroid?
What is the closest perihelion an asteroid in stable orbit could have? Is there a limit defined by orbital mechanics or could an object be in stable orbit, only too close that melting or sublimation ...
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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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Which solar system objects have the least stable solar orbits?
My research is not giving me anything definitive. Are the Apollo asteroids orbits less stable than the Centaurs or any Trojans, or is another class of objects in less stable solar orbits? On what ...
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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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What could be the name of a huge asteroid I watched some years ago?
Some years ago I was with my family in Venezuela. I'm not sure about the date/hour, but probably it was somewhat around 2007 in the afternoon. We were talking when one of us saw a huge meteor moving "...
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Has a near earth object in heliocentric orbit ever been bright enough to be visible to the unaided eye?
The question Can we see asteroid 1998 OR2 with unaided eye? got me thinking. Space.com's Vesta: Facts About the Brightest Asteroid says:
Vesta is the second most massive body in the asteroid belt, ...
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Can we see asteroid 1998 OR2 with unaided eye?
Will I be able to see the asteroid 1998 OR2 with the naked eye on April 29?
If so, where can I find more information on when and where I'll be able to see it?
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Help identifying a very slow-moving object during meteor shower photography
I just wonder if anyone could shed any light on this puzzle.
Two nights ago whilst I was out photographing the Lyrids meteor shower from the UK something else showed up on my images when I checked ...
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Identify moving object in the sky at night?
So last night I was looking at the sky at about 8PM EST, and I noticed this really tiny object moving pretty fast from left to right, just between the two stars in the photo. It's very difficult to ...
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How are the three character IAU Minor Planet Center's Observatory Codes assigned? Why are some letters so popular?
Answers to Latitude, longitude and altitude of Ckoirama Observatory; where can things like this be looked-up? point to https://www.minorplanetcenter.net/iau/lists/ObsCodesF.html which currently lists ...
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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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Is 486958 Arrokoth (2014 MU69 aka Ultima Thule) the only solar-system object determined to be binary by occultation?
The asteroid 486958 Arrokoth was discovered to be binary by astronomers lugging a bunch of telescopes around (I think) camping with them. The timing offered additional astrometry for the orbit ...
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Temporary family member 2020-CD3
So, recently I came to know that this asteroid is orbiting Earth from past 3 years and still it is orbiting. It is kind of a mini Moon to the Earth know to have come from asteroid-belt.
Is there ...
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What is the typical chemical composition of the most common asteroid types?
I'm trying to make a semi-scientific accurate game where you can find/mine asteroids. I want the composition of asteroids, and how common they are to be correct. Or at least as close to correct as ...
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What's the difference between semi-major axis and apoapsis?
The semi-major axis is half of the diameter of the major axis of an ellipse by definition. So how does that make it any different from apoapsis, the furthest point an object is from a parent body in ...
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What are other names for planetoids that aren't orbiting a solar system, but hurtling through space?
I'm trying to think of a good word for an asteroid/planetoid that has no stable orbit but has been ejected from a system and is passing close to a sun. Any help?
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If we've only observed Oumuamua as a single pixel, how can we know its shape?
On a separate Oumuamua question (Oumuamua alien space junk?), I was confused how shape could be inferred from a single pixel, per another user's (@Uwe) comment. It was suggested I ask this question ...
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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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Oxygen isotope analysis [duplicate]
Where can I get a oxygen isotope analysis $^{18}O$ / $^{16}O$ vs $^{17}O$ / $^{16}O$ done commercially ? I witnessed a meteorite fall near me; it looks to be martian andesite. My first number $SiO_2$ ...
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Is there a way to tell the difference between earth andesite from Mars
I'm curios if there is a way to test if this sample might be Martian andesite.
What type of oxygen isotope (or other) test can be done to address this in some way?
As background, any information ...
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1answer
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What did i see go by saturn?
I was looking at saturn through a basic reflective telescope. I had it focused and could see the rings. To the left a small dim white dot came across my view passing in about 3 seconds from my north ...
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Could there be a M-type asteroid beyond Jupiter?
Is there any reason to think an M-type asteroid could not have migrated beyond Jupiter and entered an orbit similar to the Centaurs?
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What makes scientists already so certain that Comet C/2019 Q4 (Borisov) is a comet and not an asteroid?
US Naval Research Laboratory scientist Dr. Karl Battams has recently tweeted
Unlike 'Oumuamua, whose asteroid-or-comet nature still gets debated, this one is definitely a comet. If it is ...
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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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How big a rock can hit the sun and it not matter? [duplicate]
If a rock the size of Oumuamua were to crash into the sun ā assume central collision ā would it materially affect the sunās behaviour? Would unaided humans (rather than sun-tastic special telescopes) ...
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Plant on large Asteroid?
I'm just curious if it is possible for a plant to survive on a large asteroid. Some say no, some say it depends.
With the scenario of an asteroid at about 1 AU from the Sun, receiving a similar ...
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Tallest cliffs, by falling duration
If you threw something over a certain cliff on a moon of Uranus, it would take over ten minutes to hit bottom.
By this measure, local fall time rather than absolute height, what are the near ...
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Are these stars in MASCOT image of Ryugu?
Are these stars in this MASCOT image of Ryugu?
Larger image:
https://www.sciencealert.com/images/2019-08/processed/RocksOfRyuguStranglyFamiliar_1024.jpg
They seem too bright to be stars (if the ...
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2019OK energy at impact
The asteroid 2019 OK recently passed at 77.000km of the Earth, with an estimated size of 50-130m.
But if this asteroid had crashed onto the Earth, what would have been its kinetic energy on impact? ...
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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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What resources do C-Type(Carbonaceous) Asteroids contain?
What resources do C-Type asteroids contain? The research I've done has come up with carbon, but what form is the carbon in? Graphite, diamonds, coal, or some other material?
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Where asteroids disappear
Scientists claim that objects left on the Moon can lie hundreds of years in the same condition like astronaut Charles Duke family photo. Why we don't see remains of asteroids inside or around craters? ...
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What causes these asteroid trails to be so strangely shaped and repeated?
The Phys.org news item Hubble is the ultimate multitasker: Discovering asteroids while it's doing other observations includes the image below.
What causes these asteroid trails to be so strangely ...
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How long does it take for an asteroid to get to Earth?
How long does it take an asteroid to get from the asteroid belt, to Earth? I know the asteroids don't go directly from the asteroid belt to Earth, but I know it's not quick, either. The time probably ...
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Has Hubble ever been used to try to image a near Earth asteroid?
This answer points out that the near Earth asteroid Apophis will likely be close to 2 arcseconds in diameter as seen from Earth during its close approach in 2029. I speculate that if the Hubble Space ...
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What's the number density of `Oumuamua like objects?
Recently, the fly-through the Solar system of the inter-stellar object (ISO) `Oumuamua caused quite a stir in the astronomy community. I wonder whether there are reliable estimates for the (local) ...
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What if there was an asteroid belt with the mass of a planet?
In the past, the asteroid belt was thought to be the remains of a shattered planet. Of course, that was all pseudoscience, the mass of the asteroid belt being 4% of the moon. I've been wondering, what ...
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What would you find within a void?
I'm aware that voids are relatively empty regions of the universe, but just how empty can they be? Wikipedia states that voids have 'few or no' galaxies, but I can't find much else.
To make my ...
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If a solar system were surrounded by a cloud of debris, is it possible for a planet's orbit to intersect it?
I'm doing research for a story that I'm writing and I'd like some physics advice on whether a hypothetical system of celestial bodies is possible.
Suppose the following:
A system of planets orbiting ...
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How to check what telescopes were looking at a certain portion of sky at a particular time?
I have some data that I collected from observations at a specific RA, DEC and I am trying to figure out what telescope surveys were looking at that portion of the sky at that particular time? I am ...
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Are there any estimates for the combined mass of all near earth objects (NEOs)?
I tried looking around but couldn't find any sources attempting to answer this particular question. It's obviously impossible to know the exact answer, but all I'm looking for is an estimate. My ...
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A quantitive estimate of the size above which celestial bodies must be near-spherical [duplicate]
Asteroids and smaller celestial objects tend to be odd-shaped, whereas planets are always spherical (or slightly oblate due to their spin). The reason obviously is that for sufficiently large masses/...
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What would happen if asteroid 99942 Apophis collides with the earth?
In the news recently it's been said that in 2029 the asteroid called Apophis, aka 'The God of Chaos', will fly by very close to earth. To quote Geek.com
In 2029, a massive asteroid called 99942 ...
