Starship Asterisk*

johnnydeep wrote: ↑Mon Sep 04, 2023 1:18 pm

emc wrote: ↑Mon Sep 04, 2023 4:36 am

orin stepanek wrote: ↑Sun Sep 03, 2023 4:24 pm fragb73p_hst_960.jpg
Comets are fascinating snowballs! I wonder how much of Earths
ocean came from comets?

If the Big Bang theory is correct, everything came from a single point. So wouldn’t everything have started together? Then during the expansion a P-R effect would have affected the distribution of matter? So there’s no human way of telling how much?

Chris Peterson wrote: ↑Sun Sep 03, 2023 2:19 pm

It's the Poynting-Roberstson effect, a drag force involving radiation pressure. It slowly clears the Solar System of dust by causing it to decay into the Sun. (Of course, we have comets that are always replenishing that dust.)

Chris, Was my reply to Orin a correct usage of the P-R effect?

orin stepanek wrote: ↑Sun Sep 03, 2023 4:24 pm d1bb1bcb8e244356d0bd053e134344a3.jpg
Kitty enjoying a sun bath!

Orin,
Cute kitty. But a stretch for this thread.

Dang! I can’t remembered how to post the images. All I get is the image file name when I quote.

I'm not Chris, but I don't think the P-R effect had much at all to do with the large scale aftermath of the Big Bang, or even the early formation of the Solar System. Comets (just "dirty snowballs" per Carl Sagan) were plentiful in the nascent Solar System, and were bombarding all forming planets and planetesimals. I'd bet that MOST of Earth's water originated from them. But I'm not sure if we could ever figure out an accurate graph of the Earth's water content over time from 4.5 Byrs ago to the present. Chris will no doubt helpfully point out where I'm "all wet" in my suppositions here, if necessary. :=)

And yes, the kitty is indeed a bit of a "stretch" for this thread! (yes, I do sometimes understand jokes!)

And to post images you either use the [img], [img2] or [img3] tags, using the buttons provided, or upload images from your local machine as attachments, using the Attachments tab interface below the posting text box.

bystander wrote: ↑Mon Sep 04, 2023 3:06 pm

emc wrote: ↑Mon Sep 04, 2023 4:36 am Dang! I can’t remembered how to post the images. All I get is the image file name when I quote.

How to post images

johnnydeep wrote: ↑Mon Sep 04, 2023 1:18 pm

emc wrote: ↑Mon Sep 04, 2023 4:36 am

orin stepanek wrote: ↑Sun Sep 03, 2023 4:24 pm fragb73p_hst_960.jpg
Comets are fascinating snowballs! I wonder how much of Earths
ocean came from comets?

If the Big Bang theory is correct, everything came from a single point. So wouldn’t everything have started together? Then during the expansion a P-R effect would have affected the distribution of matter? So there’s no human way of telling how much?

Chris Peterson wrote: ↑Sun Sep 03, 2023 2:19 pm

It's the Poynting-Roberstson effect, a drag force involving radiation pressure. It slowly clears the Solar System of dust by causing it to decay into the Sun. (Of course, we have comets that are always replenishing that dust.)

Chris, Was my reply to Orin a correct usage of the P-R effect?

orin stepanek wrote: ↑Sun Sep 03, 2023 4:24 pm d1bb1bcb8e244356d0bd053e134344a3.jpg
Kitty enjoying a sun bath!

Orin,
Cute kitty. But a stretch for this thread.

Dang! I can’t remembered how to post the images. All I get is the image file name when I quote.

I'm not Chris, but I don't think the P-R effect had much at all to do with the large scale aftermath of the Big Bang, or even the early formation of the Solar System. Comets (just "dirty snowballs" per Carl Sagan) were plentiful in the nascent Solar System, and were bombarding all forming planets and planetesimals. I'd bet that MOST of Earth's water originated from them. But I'm not sure if we could ever figure out an accurate graph of the Earth's water content over time from 4.5 Byrs ago to the present. Chris will no doubt helpfully point out where I'm "all wet" in my suppositions here, if necessary. :=)

And yes, the kitty is indeed a bit of a "stretch" for this thread! (yes, I do sometimes understand jokes!)

And to post images you either use the [img], [img2] or [img3] tags, using the buttons provided, or upload images from your local machine as attachments, using the Attachments tab interface below the posting text box.

emc wrote: ↑Mon Sep 04, 2023 5:00 pm

johnnydeep wrote: ↑Mon Sep 04, 2023 1:18 pm

emc wrote: ↑Mon Sep 04, 2023 4:36 am
If the Big Bang theory is correct, everything came from a single point. So wouldn’t everything have started together? Then during the expansion a P-R effect would have affected the distribution of matter? So there’s no human way of telling how much?


Chris, Was my reply to Orin a correct usage of the P-R effect?


Orin,
Cute kitty. But a stretch for this thread.

Dang! I can’t remembered how to post the images. All I get is the image file name when I quote.

I'm not Chris, but I don't think the P-R effect had much at all to do with the large scale aftermath of the Big Bang, or even the early formation of the Solar System. Comets (just "dirty snowballs" per Carl Sagan) were plentiful in the nascent Solar System, and were bombarding all forming planets and planetesimals. I'd bet that MOST of Earth's water originated from them. But I'm not sure if we could ever figure out an accurate graph of the Earth's water content over time from 4.5 Byrs ago to the present. Chris will no doubt helpfully point out where I'm "all wet" in my suppositions here, if necessary. :=)

And yes, the kitty is indeed a bit of a "stretch" for this thread! (yes, I do sometimes understand jokes!)

And to post images you either use the [img], [img2] or [img3] tags, using the buttons provided, or upload images from your local machine as attachments, using the Attachments tab interface below the posting text box.

Thanks johnnydeep! Nice to meet you!