Questions tagged [comets]
Icy bodies that usually consist of methane, water, and other materials that originate from beyond the jovian planets, and occasionally fall into the inner solar system giving off a massive tail as material is boiled off.
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Cooling the early earth
My son had this theory that the icy comets cooled the hot earth during the late heavy bombardment. What do we know about this cooling effect on the early evolution of the earth? He intended his theory ...
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3rd brightest ever object in the sky
What’s the 3rd brightest ever recorded object in the sky?
For example Venus is normally the 3rd brightest object in the sky.
However there have been the occasional comet or Supernova that have ...
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Calculating Comet Position at a Given Julian Date with Available Orbital Elements
I have some orbital elements for comet P/2004 R1 (McNaught) from this dataset and I would like to calculate its position around the sun (x, y, z coordinates where the sun is at the origin) at a ...
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Are short-period comets more stable (in their orbits) than long-period ones?
Why the sharp distinction between short-period (P) comets of less-than-200-year orbits and those (C) with even slightly longer ones?
To explore the possibility that it has to do with stability, I will ...
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Most accurate way of measuing the radius of a rubble-pile comet in an N-body simulation?
I have written an N-body simulation (close to finished) in C++ which focuses on the tidal disruption of comets.
I allow comets to be constructed in 2 ways:
Via my HCP (hexagonal-closest-packing) ...
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What is the best estimate for the radius of Shoemaker-Levy 9?
I have been digging through various scientific articles on modelling the breakup of SL9 to attempt to ascertain its intial size, yet the various estimates vary tremendously.
A radius of 700 m - 1000 m ...
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How commonly observed is H2 forming in H2O ice, among comets?
How common is H2 forming under a shell of normal ice, among comets?
The context is the Oumuamua discussion, and its latest tentative solution. "Acceleration of 1I/‘Oumuamua from radiolytically ...
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How is Halley's comet still in one piece?
According to the first answer of This question parts of Halley's comet hit the Earth every spring as part of the Eta Aquarid meteor shower. If this is true, then how is the comet still in one piece? ...
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How do we know that a comet passed by earth 50,000 years ago?
This article (https://gothamist.com/news/a-green-comet-is-sailing-over-new-york-and-earth-for-the-first-time-in-50000-years) claims that a comet will pass by earth soon for the first time in 50,000 ...
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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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How do we know that ice from the S1094b event was from Mars surface and not from the impactor?
The recent news story NASA’s InSight Lander Detects Stunning Meteoroid Impact on Mars, about an impact that occurred on Mars on December 24, 2021 (event S1094b), shows a picture of the impact crater, ...
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Time of comet at perihelion query
In Practical Astronomy With Your Calculator Or Spreadsheet by Duffett-Smith and Zwart, the authors write (in relation to calculating cometary positions):
The longitude of the comet is not usually ...
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Could a rogue comet perturb a frequently occurring meteor shower to the extent that debris falls on Earth...and dislodges satellites?
This is for a work of fiction that I started five years ago. Clever people from Astronomy Stacks answered several questions for me back then. Now that I am in the final edit of this manuscript, I find ...
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If a supernova explodes all it's comets into space, can they reach a big number of star systems?
If there's DNA life that arises on a warm planet 2 billion years after the big bang, and meteorite collisions on the planet propagate DNA unicellular organisms into millions of icy rocks orbiting the ...
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calculating MPC orbital uncertainty parameter U
I'm trying to understand how the orbital uncertainty parameter 'U' introduced by the Minor Planet Center (MPC) is actually calculated for minor bodies. This wikipedia page gives the formulae to be ...
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Comet Bernardinelli-Bernstein; could it be a "planet-killer" and what could prevent it from getting close to us?
The huge "mega" comet C/2014 UN271 (Bernardinelli–Bernstein) 80 miles wide is coming towards Earth from the edge of our Solar System.
It is supposed to only get to the middle of our Solar ...
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How is a comet visible when far from the Sun
The latest news tells of a super large "mega" comet C/2014 UN271 (Bernardinelli–Bernstein)
approaching the Solar System in about 9 years.
It must be very far from the Sun, so how do we ...
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How to model the kinematics of gases expelled from comets and planetary atmospheres?
Once the ices of comets sublimate, where do they move to, and with which equations do you describe their motion in the interplanetary medium? Similarly, where do the gases that are stripped from the ...
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What exactly did ALMA observe at 20 AU from the "Mega Comet Arriving From the Oort Cloud" that will pass in 2031?
Gizmodo's Mega Comet Arriving From the Oort Cloud Is 85 Miles Wide
says:
For the new study, Lellouch and his colleagues used the Atacama Large Millimeter Array (ALMA) in Chile to refine the comet’s ...
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What is going on with comet C/2021 A1 Leonard? Is it going to be bright this weekend or not?
I have to plan an excursion to try to find clear evening skies to try to see if we can spot comet C/2021 A1 Leonard about 10 to 15° above the ocean in the Southwest after sunset this weekend.
I'm ...
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How close to escape velocity are most Oort-cloud comets?
User @antlersoft wrote a nice answer to my question on the difference between barycentric and heliocentric models of the solar system when applied to comets (edge cases of the systems). In a comment, @...
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What is the difference between barycentric-centered and heliocentric-centered coordinates?
When talking about celestial bodies orbiting the sun with a decently circular orbit or small aphelion, the heliocentric orbital parameters are almost identical to the barycentric parameters. However, ...
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What observational data was there that comet Leonard C/2021 A1 might have been dimming and/or breaking up?
Space.com's Comet Leonard, the brightest of the year, is fading and acting strange seems to be full of inexact language, like "something's wrong" and "unhealthy" and "goner&...
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Make a guide map to comet comet Leonard C/2021 A1 using Skyfield
Sky and Telescope's How Bright will Comet Leonard Get? includes the skymap and projected (possible) light curve for comet Leonard C/2021 A1 that will potentially reach +4 magnitude this month. It has ...
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Specific impulse of cometary outgassing?
Note: This question is related to Average DeltaV applied to a comet during outgassing?
Rocket engines have a parameter called "specific impulse," which is the measurement (in seconds) of how ...
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Average DeltaV applied to a comet during outgassing?
Comets' orbits often change during perihelion passage due to the outgassing of volatiles. So I am wondering, how much change in velocity is applied each perihelion pass? What does this depend on?
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Role of aerobraking in cometary orbits?
I'm doing some research about comet perturbations, and have noticed that the outbound aphelion is often different from the inbound aphelion, particularly due to the gravitational influence of the ...
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The Kuiper Belt and Oort cloud [closed]
How come the comets and asteroids in the Kuiper belt and Oort cloud are kept in a gravitational field and they don't get pushed and pulled by the planets around them? I get why comets in the Oort ...
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Why haven't we had an "asteroid attack" until now?
We know that there is a big and dense ring of asteroids between the orbits of Jupiter and Mars and also "Trojans" and "Greeks" in Jupiter's orbit too. We also know that
there are ...
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Is there any chance Comet Bernardinelli-Bernstein could collide with Earth?
At a size of 100 kilometers, this comet is ten times the one that exterminated the dinosaurs on Earth. It is headed towards our Solar System and expected to arrive in 2031. It is projected to swing by ...
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Disk-resolved vs disk-averaged photometry?
I have already read this question about the difference between disk-integrated and disk-resolved photometry. But what exactly is the difference between disk-resolved and disk-averaged photometry?
I am ...
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Astronomic objects (and their distribution functions) appearing in an old computer game?
Many decades ago, when I learned coding, I was also reading a (red) book on the programming the 8080 processor which was full of code listings and their description. I was in particular fascinated by ...
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Mass loss rate in a typical visible-from-Earth comet
What is the typical range of a comet's mass loss per second to its dust and gas tails, while it is naked-eye visible from Earth?
I'm aware this is going to be a very broad range and expect it to cover ...
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How does a comet crumble? Are there models for that?
Edit: Initially, the title was How does the crumbling sound?
I am curious how comets degradate or even disintegrate over time, in particular while they are close enough to the Sun to have tails. Is ...
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Whether the comet is moving in an elliptical or hyperbolic orbit around the sun?
The time of observation after the first observation (in years), the distance between the earth and the comet (in AU) and the angle between the sun and the comet (in radians) is given.
How to find ...
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Details about the next big comet 2014 UN271?
The announcent of the massive trans-Neptunian object 2014 UN271 to be a comet is rather new (June 22nd, 2021) and really exciting. That comet is rather huge (~100km diameter) and "falling toward ...
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Dotted line of moving objects observed on May 5th and May 12th [duplicate]
I saw a dotted line shooting star-like object May 5th and May 12th. It was longer than any meteor/shooting star tail or trail I've ever seen before. I mean longer in every way, the distance it ...
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Is scattering efficiency of dust related to albedo?
I know that the scattering cross-sections of dust in comets depend on the scattering efficiency. A higher scattering efficiency leads to an increase in brightness. Therefore, does it mean that this ...
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I have a question about the wording in a paper about a planetary system and comets
I was reading a paper. This is the paper:
https://arxiv.org/abs/2006.01711 (https://ui.adsabs.harvard.edu/abs/2020MNRAS.496.4979D/abstract
In the method section in the second paragraph there is a bit ...
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Does this galaxy resemble the Milky Way, and is it relatable as the "template" for the Milky Way?
Taking a look at this photo of comet 2I/Borisov and a background galaxy (2MASX J10500165-0152029):
And compare it to this rendition of the Milky Way:
The two galaxies slightly resemble each other. ...
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A comet orbits the Sun in the same plane as Earth's orbit
If the Earth around the Sun follows a practically circular orbit of radius equal to one astronomical unit, determine its orbital speed in astronomical units per year.
If the Earth around the Sun ...
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How do comets' nuclei stick together?
Comets are commonly called icy dust balls or dirty snowballs and as such rather light:
Known comets have been estimated to have an average density of $0.6 {\rm g}/{\rm cm}^3$. Because of their low ...
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Do some comets spin? If so, how fast?
The GIF below is copied from my question earlier What might a CN filter be in the context of comet watching? Is it showing dust, or gas, or something else? where I'd said:
In this post on the website ...
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What calculations show that Comet Shoemaker-Levy 9 orbited Jupiter for several decades before its spectacular impact? (Chodas, Sekanina & Yeomans)
This answer to A moon in eccentric orbit dipping below Roche limit includes the following about Comet Shoemaker–Levy 9
Here is a nice figure of its last passes:
I looked up "fragment A" in ...
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Can a supernova or a close passing star create a transient sun gravity focus "habitable zone"?
This question was inspired by the previous question Would a black hole passing next to a star create a deadly focal point due to gravitational lensing?. I understand, as gravity also acts on light, ...
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The creation of comets
How are comet and meteors made, and what causes them to travel through space so fast? I have tried researching, but I decided this was the faster way.
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Why do we only have one major meteor shower from 3200 Phaethon?
When talking to my son about the Geminid meteor shower tonight, we read up on 3200 Phaethon, and were curious: why is there only one meteor shower from 3200 Phaethon, and not two? Given its orbit, ...
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Are falling evaporating bodies (FEBs) and exocomets the same thing? How does one know they're falling and evaporating?
Looking for a (short) list of comets with heliocentric escape velocity I stumbled upon Wikipedia's exocoments which like exoplanets, are bound to other stars. I should have been looking for "...
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Why would a planet form a cometlike tail under conditions of weaker rather than stronger solar wind?
This question is prompted by one posted on the worldbuilding stack exchange:
https://worldbuilding.stackexchange.com/questions/189701/could-this-planets-tail-be-visible
I understand that the ionized ...
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What comet's tail did Earth pass through before Halley's?
This answer to Any record of the Earth passing through the tail (not trail) of a comet? mentions
Earth passed through the tail of Halley's Comet in 1910. It caused a bit of a panic due to claims that ...
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