How hard is it to detect extinct comets?

In summary, cometary nuclei have a very low albedo which makes detecting extinct comets difficult, but it is estimated that around 6% of near Earth asteroids may actually be extinct comets. The detection of these objects relies on size and albedo, and it is possible for comets to be detected before they start outgassing. The exact size and distance at which this is possible may vary depending on the comet's composition.
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xpell
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TL;DR Summary
Since cometary nuclei have such a low albedo, are they very difficult to detect?
Hi! I have read that cometary nuclei have a very low albedo, even lower than coal or asphalt. Because of this, they absorb lots of light and heat rather than reflecting them. So I was wondering how hard is it to detect extinct comets. Could the solar system be full of dead nuclei buzzing around that we are just unable to "see" using current technology, or are they usually detected somehow?

Thank you in advance!
 
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hi ya
xpell said:
Summary:: Since cometary nuclei have such a low albedo, are they very difficult to detect?

I have read that cometary nuclei have a very low albedo, even lower than coal or asphalt.
"I have read..." is not a good thing without context or links to where as we don't know what you
were reading, how reliable it was or if you may or may not have taken it out of context ( misunderstood).

Generally, comets are classified as dirty snowballs, and don't always have a completely solid nuclei.
Hence why I would like to know what you were reading.
xpell said:
So I was wondering how hard is it to detect extinct comets.

Have to say, I had never heard of "extinct" comets had to google that and after reading I get the idea.

Wiki has a reasonable article on such things
https://en.wikipedia.org/wiki/Extinct_comet

Their suggestion is that some 6% of near Earth asteroids are likely to be extinct comets.
And this sort of answers your question about their detection, it would be much the same as
any other asteroid with size and albedo being the main factors in their detection.Dave
 
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Hi, Dave,

davenn said:
"I have read..." is not a good thing without context or links to where as we don't know what you
were reading, how reliable it was or if you may or may not have taken it out of context ( misunderstood).
Well, I have read it in many different places, including that Wikipedia article. Their average albedo seems to be around 0.05, which is really low...
davenn said:
Their suggestion is that some 6% of near Earth asteroids are likely to be extinct comets.
And this sort of answers your question about their detection, it would be much the same as
any other asteroid with size and albedo being the main factors in their detection.
...and that's why I was wondering if there's the possibility of lots of "non-near-Earth" objects orbiting the Sun which are no longer outgassing and are impossible to detect using currently available observation technology, or there are instruments or techniques to find them.

Another possible, closely related question would be: "Is it possible to detect a comet before it starts outgassing? How big / far away?"
 
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xpell said:
Hi, Dave,
………………………...

Another possible, closely related question would be: "Is it possible to detect a comet before it starts outgassing? How big / far away?"

Would depend on size but as a generalisation most start outgassing between the orbits of Jupiter and Saturn.
There, of course, depending on the composition etc, will be variations
 

1. How do scientists detect extinct comets?

Scientists use various methods to detect extinct comets, such as studying the orbits and trajectories of known comets, analyzing the chemical composition of meteorites, and using telescopes to search for faint objects in the outer solar system.

2. What makes it difficult to detect extinct comets?

Extinct comets are difficult to detect because they have lost most of their volatile materials and no longer produce a visible coma or tail. They also have highly elliptical orbits that can take them far from the sun, making them harder to spot.

3. Can extinct comets be mistaken for other objects?

Yes, extinct comets can be mistaken for other objects such as asteroids or Kuiper Belt objects. This is because they may appear as small, faint points of light and have similar orbits to these objects.

4. How do scientists determine if a comet is extinct?

Scientists determine if a comet is extinct by analyzing its chemical composition. Extinct comets have a different chemical makeup compared to active comets, as they have lost most of their volatile materials.

5. Why is it important to detect extinct comets?

Detecting extinct comets is important because it can provide valuable information about the early solar system and the formation of planets. It can also help scientists better understand the potential impact of comets on Earth and other planets.

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