Asteroid 33 Polyhymnia

Get your science fix here: research, quackery, activism and all the rest
Post Reply
User avatar
Boustrophedon
Stummy Beige
Posts: 2840
Joined: Mon Nov 11, 2019 3:58 pm
Location: Lincolnshire Wolds

Asteroid 33 Polyhymnia

Post by Boustrophedon » Sun Oct 15, 2023 11:22 pm

Obviously I was tempted to put this in weighty matters.

Asteroid 33 Polyhymnia seems to have a density of around 75 g/cm3 which is way heavier than any element so far discovered, however the observations needed to make this calculation are difficult owing to its small size and have only been done once.

This article seems to suggest that super heavy elements may exist around Z=164 :


I would like to read the research paper it quotes: Superheavy elements and ultradense matter, Evan LaForge, Will Price & Johann Rafelski.
https://link.springer.com/article/10.11 ... 23-04454-8
However this is behind a paywall, anyone know of anywhere with a free copy?
Hjulet snurrar men hamstern är död.

philip
Bank Butt
Posts: 25
Joined: Tue Nov 12, 2019 10:55 am

Re: Asteroid 33 Polyhymnia

Post by philip » Sun Oct 15, 2023 11:52 pm


User avatar
Grumble
Light of Blast
Posts: 4690
Joined: Mon Nov 11, 2019 1:03 pm

Re: Asteroid 33 Polyhymnia

Post by Grumble » Mon Oct 16, 2023 5:38 am

Surely measuring the volume of an asteroid must have quite large error bars, unless it’s really well lit.
where once I used to scintillate
now I sin till ten past three

User avatar
dyqik
Princess POW
Posts: 7408
Joined: Wed Sep 25, 2019 4:19 pm
Location: Masshole
Contact:

Re: Asteroid 33 Polyhymnia

Post by dyqik » Mon Oct 16, 2023 7:14 am

Grumble wrote:
Mon Oct 16, 2023 5:38 am
Surely measuring the volume of an asteroid must have quite large error bars, unless it’s really well lit.
And it really depends on what the spin axis is. Imagine a cigar shaped object spinning around its long axis, which is pointing almost exactly in your direction, vs a cigar spinning around a short axis at 90 degrees to you.

User avatar
Boustrophedon
Stummy Beige
Posts: 2840
Joined: Mon Nov 11, 2019 3:58 pm
Location: Lincolnshire Wolds

Re: Asteroid 33 Polyhymnia

Post by Boustrophedon » Mon Oct 16, 2023 8:50 am

philip wrote:
Sun Oct 15, 2023 11:52 pm
Is this it? https://arxiv.org/abs/2306.11989
Thanks.
Hjulet snurrar men hamstern är död.

IvanV
Stummy Beige
Posts: 2585
Joined: Mon May 17, 2021 11:12 am

Re: Asteroid 33 Polyhymnia

Post by IvanV » Mon Oct 16, 2023 3:49 pm

Accessing an obscure source, I find that these data on the mass and size of 33 Polyhymnia were established over a decade ago. In all that time, no other scientists proposed it was made of ultra-dense matter, as opposed to measurement shortcomings. How dull of them.

IvanV
Stummy Beige
Posts: 2585
Joined: Mon May 17, 2021 11:12 am

Re: Asteroid 33 Polyhymnia

Post by IvanV » Mon Oct 16, 2023 4:42 pm

dyqik wrote:
Mon Oct 16, 2023 7:14 am
Grumble wrote:
Mon Oct 16, 2023 5:38 am
Surely measuring the volume of an asteroid must have quite large error bars, unless it’s really well lit.
And it really depends on what the spin axis is. Imagine a cigar shaped object spinning around its long axis, which is pointing almost exactly in your direction, vs a cigar spinning around a short axis at 90 degrees to you.
It has an orbital period of a little under 5 years. It won't be pointing its spin axis at us all the time. We should have plenty of time when we get side-on views, if we looked.

But it does have a rather eccentric orbit. We'd probably only get a decently close approach for a few weeks about every 10 years or so. And then someone has to be bothered to be trying to look. So you can imagine a scenario where it tends to be pointing its narrow end, if it has one, in roughly our direction around perihelion, or else just whenever we happened to be occasionally looking.

User avatar
Gfamily
Light of Blast
Posts: 5124
Joined: Mon Nov 11, 2019 1:00 pm
Location: NW England

Re: Asteroid 33 Polyhymnia

Post by Gfamily » Mon Oct 16, 2023 5:03 pm

IvanV wrote:
Mon Oct 16, 2023 3:49 pm
Accessing an obscure source, I find that these data on the mass and size of 33 Polyhymnia were established over a decade ago. In all that time, no other scientists proposed it was made of ultra-dense matter, as opposed to measurement shortcomings. How dull of them.
The article cited by Wikipedia acknowledges that the calculated density for 33 Polyhymnia is 'unrealistic' (page 20)
https://arxiv.org/pdf/1203.4336.pdf

The source of the mass is this paper here from 2010 -
https://arxiv.org/pdf/1011.4419.pdf - the method seems to rely on measuring the perturbations in the asteroid's orbit against a dynamic model of the Solar System. I notice that there is no figure for the mass of 33 Polyhymnia in the most recent (2019) paper.
My avatar was a scientific result that was later found to be 'mistaken' - I rarely claim to be 100% correct
ETA 5/8/20: I've been advised that the result was correct, it was the initial interpretation that needed to be withdrawn
Meta? I'd say so!

Post Reply