Agreed terms - what subject would you like next?

[Catastrophe]

Please post your ideas here.

Black Hole?

Singularity?

Alternate universe?

Any more?

 

[Patrick fenex]

What evidence led to the conclusion that the mega-comet is indeed an oort cloud object?

 

[sam85geo]

Please post your ideas here.

Black Hole?

Singularity?

Alternate universe?

Any more?

Just a whim. How about Einstein's "Spooky action at a distance"; i.e.: particle entanglement, but on more massive objects. I'm thinking about how such could be applied to gambling/betting possibly even to horse racing.

 

[Catastrophe]

What evidence led to the conclusion that the mega-comet is indeed an oort cloud object?

We are looking to explain terms in general. How about Oort Cloud? Of course, comets would feature heavily. Cat

 

[Patrick fenex]

Perhaps this, what is the oldest population one star that's been identified?

 

[Catastrophe]

"Population I includes stars with a wide range of ages. While some are as old as 10 billion years, others are still forming today. For example, the Sun, which is about 5 billion years old, is a population I star. But so are the massive young stars in the Orion Nebula that have formed in the last few million years.!! Google.

How about Population I II III stars as a whole, to include, of course, ages?

Cat

 

[sam85geo]

I'm looking forward to where this thread might lead. A lot of succinct ideas that are very helpful to novices may be presented.

 

[dsnyrocketengine]

alternative methods of space travel

 

[Catastrophe]

I'm looking forward to where this thread might lead. A lot of succinct ideas that are very helpful to novices may be presented.

Thank you. A start has been made under Population stars - agreed terms help sensible discussion. Cat

 

[Patrick fenex]

"Population I includes stars with a wide range of ages. While some are as old as 10 billion years, others are still forming today. For example, the Sun, which is about 5 billion years old, is a population I star. But so are the massive young stars in the Orion Nebula that have formed in the last few million years.!! Google.

How about Population I II III stars as a whole, to include, of course, ages?

Cat

I wasn't aware of cat one stars being that old. They must be dwarf stars otherwise they would have left the main sequence eons ago. If what you're saying is true, then that means the universe has been capable of supporting sentient, intelligent, alien life for almost 10 billion years!! That's astounding!

 

[Catastrophe]

Patrick, I try to be most careful Here was my source. I will look into it, in case my source contained an error. Many thanks for pointing it out. Cat



25.5 Stellar Populations in the Galaxy – Astronomy
https://pressbooks.online.ucf.edu › chapter › 25-5-stella...

Population I includes stars with a wide range of ages. While some are as old as 10 billion years, others are still forming today. For example, the Sun, which is about 5 billion years old, is a population I star. But so are the massive young stars in the Orion Nebula that have formed in the last few million years. Population II, on ...

 

[Patrick fenex]

Thanks for your prompt reply. I wasn't trying to be nit-picky, I was just shocked by what it could mean.

 

[Catastrophe]

Patrick. I just found this in Astronomynotes.com (I don't know them?)
"he Population I stars are in the disk component of the Galaxy. They have a wide range of ages, from 0 to 10 billion years old. The youngest ones are in the spiral arms. Population I star orbits are orderly: roughly circular orbits close to the mid-plane of the galactic disk. Young star clusters made of Population I stars are called open clusters because the stars are loosely bound together, in contrast to the old, concentrated globular clusters."
My emphasis.

I found another at 10 billion years, but their 'metals' content was only 10% Sun, which seems on the low side. Cat

 

[Patrick fenex]

Patrick. I just found this in Astronomynotes.com (I don't know them?)
"he Population I stars are in the disk component of the Galaxy. They have a wide range of ages, from 0 to 10 billion years old. The youngest ones are in the spiral arms. Population I star orbits are orderly: roughly circular orbits close to the mid-plane of the galactic disk. Young star clusters made of Population I stars are called open clusters because the stars are loosely bound together, in contrast to the old, concentrated globular clusters."
My emphasis.

I found another at 10 billion years, but their 'metals' content was only 10% Sun, which seems on the low side. Cat

Indeed, if your source is correct, then the oldest cat one stars could very easily have been born in globular clusters, since galactic stellar nurseries would have been rare to non-existent so long ago.

 

[Catastrophe]

Thanks for your prompt reply. I wasn't trying to be nit-picky, I was just shocked by what it could mean.

No problem. I am grateful to you for pointing it out. If it is Pop I, I think it must be pretty borderline.

 

[Helio]

I would guess that the distinction between populations is tied to metallicity. It is the metals that makes one star different than another, for the same mass.

 

[Helio]

Another worthwhile topic is to delineate between what is metaphysics and physics, or even pseudoscience. This would be especially helpful whenever the BBT is discussed. It is very common to see people talk as if science is able to address singularities for BBT, etc.

 

[Patrick fenex]

6

Another worthwhile topic is to delineate between what is metaphysics and physics, or even pseudoscience. This would be especially helpful whenever the BBT is discussed. It is very common to see people talk as if science is able to address singularities for BBT, etc.

That would be very interesting. It's ironic that you brought up metaphysics along with pseudoscience, since it is known that cosmology is one of the pillars of metaphysics. Just thought I'd throw that one in.

 

[Helio]

6

That would be very interesting. It's ironic that you brought up metaphysics along with pseudoscience, since it is known that cosmology is one of the pillars of metaphysics. Just thought I'd throw that one in.

BBT is not metaphysics, so only some things in cosmology are metaphysics.

 

[Patrick fenex]

I would guess that the distinction between populations is tied to metallicity. It is the metals that makes one star different than another, for the same mass.

It had me thinking about the apparent discrepancy between the age of the Universe and Methuselah's star. Extremely low metallicity, along with the age contraversy. I wonder if there might be some indirect method of determining whether or not Methuselah star was created after the first population 3 stars went supernova. We know that the first population three stars came into existence approximately two hundred million years after the big bang. Since the overall volume of the universe back in that era, was microscopically smaller than it is today, the Dynamics of Stellar evolution must have been strikingly different.

 

[Catastrophe]

HD 140283 - Wikipedia
https://en.wikipedia.org › wiki
HD 140283 (or the Methuselah star) is a metal-poor subgiant star about 200 light years away from the Earth in the constellation Libra, near the boundary with ...
‎List of oldest stars · ‎Stellar population · ‎Billion years · ‎Subgiant


Cat

 

[Helio]

It had me thinking about the apparent discrepancy between the age of the Universe and Methuselah's star. Extremely low metallicity, along with the age contraversy. I wonder if there might be some indirect method of determining whether or not Methuselah star was created after the first population 3 stars went supernova. We know that the first population three stars came into existence approximately two hundred million years after the big bang. Since the overall volume of the universe back in that era, was microscopically smaller than it is today, the Dynamics of Stellar evolution must have been strikingly different.

Yes, things were indeed different when the first stars formed. The elements were only hydrogen and helium. [There was a tiny amount of deuterium and even less lithium.]

These early stars may have all been very massive, which was great for nucleosynthesis because the more massive the star, the more heavier elements are formed, both in quantities and in atomic number.

Perhaps we can someday see some of these stars directly thanks to gravitational lensing, but that will be a huge challenge given their distance and redshift.

 

[Patrick fenex]

Please post your ideas here.

Black Hole?

Singularity?

Alternate universe?

Any more?

Alternative abiogenesis, panspermia route

 

[Catastrophe]

Yes, things were indeed different when the first stars formed. The elements were only hydrogen and helium. [There was a tiny amount of deuterium and even less lithium.]

These early stars may have all been very massive, which was great for nucleosynthesis because the more massive the star, the more heavier elements are formed, both in quantities and in atomic number.

Perhaps we can someday see some of these stars directly thanks to gravitational lensing, but that will be a huge challenge given their distance and redshift.

Strangely metallicity came up as:

Metallicity [Fe/H]

−2.40±0.10[1] dex whereas the scale iirc goes down to -4 etcetera. Cat

 

[Patrick fenex]

Yes, things were indeed different when the first stars formed. The elements were only hydrogen and helium. [There was a tiny amount of deuterium and even less lithium.]

These early stars may have all been very massive, which was great for nucleosynthesis because the more massive the star, the more heavier elements are formed, both in quantities and in atomic number.

Perhaps we can someday see some of these stars directly thanks to gravitational lensing, but that will be a huge challenge given their distance and redshift.

Alternative abiogenesis, panspermia route