[HN Gopher] The series of fortunate astrophysical events that ga...
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The series of fortunate astrophysical events that gave us Ceres
Author : dnetesn
Score : 73 points
Date : 2023-03-24 16:12 UTC (6 hours ago)
(HTM) web link (nautil.us)
(TXT) w3m dump (nautil.us)
| aa-jv wrote:
| I hope I live long enough to see the mission to 16 Psyche, a
| massive mostly-metal asteroid, which has enough resources
| (theoretically) to propel humanity into a space-based species.
| Seriously.
|
| I could imagine we send 3d printers to 16 Psyche and get
| Starships landing in return. We _could_ do this - we have the
| ability - we just don 't have the moral/ethical motivation.
|
| Nevertheless, I hope I see the results of the mission, one of
| these days. Its truly exciting.
| parchedbeluga wrote:
| I have great news for you. https://psyche.asu.edu/
|
| only have to last to 2029
| mkl wrote:
| > I could imagine we send 3d printers to 16 Psyche and get
| Starships landing in return.
|
| Where would the starships get their fuel?
| jkmcf wrote:
| They mention using Dyneema for the space elevator tether, a
| material I hadn't heard about.
|
| https://www.gearpatrol.com/outdoors/a462827/everything-you-n...
| necubi wrote:
| It's used very widely in climbing as a lighter-weight
| alternative to nylon
| sudhirvarma wrote:
| It's used on sailboats. Shows very low stretch under load.
| https://www.landfallnavigation.com/boats-parts/sailing-lines...
| asplake wrote:
| Wow: "Meanwhile they were heating up, mainly from the radioactive
| element Aluminum-26. The amount of energy this element released
| during the first 2 to 3 million years of solar system history
| amounts to more than all of the heat released by all other
| sources over the past 4.5 billion years (except for the sun, of
| course)."
| feoren wrote:
| I was surprised to see that such a silly, narrow-minded, and
| misleading statement actually came from one of the authors of
| the paper, and not an editorializing pop-science writer.
|
| First of all, it's obvious that it amounts to more than all the
| heat released by all other sources _that we know of_. How is it
| that we discover this new interesting way heat could have been
| released, and it doesn 't occur to us that maybe there are
| _other_ new interesting ways heat could have been released that
| we haven 't discovered yet? The very discovery of that
| mechanism is exactly evidence that we have _not_ yet discovered
| all possible sources of heat in the early universe. It 's crazy
| that I need to point this out.
|
| Secondly, it's worded extremely misleadingly. The article goes
| "Ceres did this; Ceres did that; it's a member of this type of
| body; these bodies involved this element; _this element_ was
| the source of a tremendous amount of heat ". What produced all
| that heat? Not Ceres. Not carbonaceous asteroids. Aluminum-26
| around the entire solar system. Most of that heat generation
| could have occurred (and probably did occur) in the core of
| Jupiter, not in Ceres. Yet it makes it sound like early Ceres
| was a huge source of heat in the solar system. This is a pretty
| extreme amount of carelessness from this author.
| icehawk wrote:
| The wording seemed fairly straightforward given the given the
| context.
|
| The sentence itself speaks about the "solar system history,"
| mentioning the sun for comparison, and the paragraph after
| that attributes the heating of planetesimals to Aluminum-26
| specifically. Ceres is not even mentioned in the two
| paragraphs that describe heating.
| PaulHoule wrote:
| Probably the most valuable real estate in the solar system. See
|
| https://arxiv.org/pdf/2011.07487.pdf
| tomrod wrote:
| This is amazing.
|
| And probably step three to being a multiplanetary species!
| rob74 wrote:
| https://archive.is/DzoJd
| teddyh wrote:
| Original title: _How Ceres, the Largest "Dark Asteroid," Survived
| the Inner Solar System_
| red-iron-pine wrote:
| A better title, for sure. 1) gives the name of the body, 2)
| doesn't imply it's near us -- "inner solar system" is still
| pretty dang far, and 3) gives a better idea what it will be
| about, namely how this asteroid is still around.
| [deleted]
| Animats wrote:
| Ceres is considered a "dwarf planet", now that it's known to
| have pulled itself into a rather good sphere. It's surprising
| that 0.03g is enough to do that.
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(page generated 2023-03-24 23:00 UTC)