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New and Amended pages 14/5/19
#1
After a couple of false starts, the Latest Updates page is now ready
https://orionsarm.com/updates
Particularly I should mention the Celestia Addon for Corona and Iota Piscium, which has a lot of different worlds and megastructures included.

14 May 2019 (Kepler 19, 50 A.T.)
New Pages
Neuropsychological Engineering :: Spinel :: Tien-Schu :: Iota Piscium (includes Celestia Addon):: Crystal Trees :: Neurotechnology :: Planetary State of Corona :: New Eureka
Amended Pages
Utopia Sphere :: Corona (Iota Piscium d) :: Gengineer Republic :: Taurus Nexus :: Euphrosyne :: Lok Mai :: Ran (Epsilon Eridani)
New Images
Mars :: The Organic Ascension Alliance :: Europe :: Dionysan Erotocracy :: The Crystal Star Domain :: Sunlines :: Yggdrasil Bush :: Ederworlds :: Ao Lai :: Tragedy of the G995
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#2
In the Crystal Trees article, the second paragraph says "guided down the truck to a root system which may be connected to other trees to gather light over an even wider area". Truck is probably supposed to be trunk.
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#3
Another thing, in the New Eureka article, Archimedes is stated to have a radius of 9.6 km and yet it seems unusually spherical for such a small object. Is there a specific reason for its roundness?
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#4
(05-15-2019, 06:42 AM)dsmike1980 Wrote: Another thing, in the New Eureka article, Archimedes is stated to have a radius of 9.6 km and yet it seems unusually spherical for such a small object. Is there a specific reason for its roundness?

1) It's not spherical. You're just looking from the wrong side.
Here's Archimedes from the 'pole'.

2) There are plenty of small asteroids that are round. Both Ryugu and Bennu's shapes are not that far off from a sphere.
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#5
Truck/trunk fixed- thanks!
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#6
(05-15-2019, 01:09 PM)The Astronomer Wrote: 1) It's not spherical. You're just looking from the wrong side.
Here's Archimedes from the 'pole'.

2) There are plenty of small asteroids that are round. Both Ryugu and Bennu's shapes are not that far off from a sphere.

Ryugu and Bennu are so shaped because of rapid rotation. Small moons in close orbits around a much larger primary are usually tidally locked.
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#7
(05-16-2019, 12:49 PM)dsmike1980 Wrote:
(05-15-2019, 01:09 PM)The Astronomer Wrote: 1) It's not spherical. You're just looking from the wrong side.
Here's Archimedes from the 'pole'.

2) There are plenty of small asteroids that are round. Both Ryugu and Bennu's shapes are not that far off from a sphere.

Ryugu and Bennu are so shaped because of rapid rotation. Small moons in close orbits around a much larger primary are usually tidally locked.

2) Bennu rotates much faster than Ryugu, and they both have roughly the same shape.

3) Also, what prevents a generic asteroid moon from assuming a roughly spherical shape?

4) The current shape does not reflect the original shape of this asteroid. It could've been sculpted by the colonists. Personally, I think its role is as a 'decoration' that bonuses as a counterweight and living space.

If you're bothered by the shape of an asteroid in a Celestia addon, you can consider asking Steve to create another shipyard model with less spherical asteroid. As for me, I think I'll just leave it like that.
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#8
(05-16-2019, 03:38 PM)The Astronomer Wrote: 2) Bennu rotates much faster than Ryugu, and they both have roughly the same shape.

3) Also, what prevents a generic asteroid moon from assuming a roughly spherical shape?

4) The current shape does not reflect the original shape of this asteroid. It could've been sculpted by the colonists. Personally, I think its role is as a 'decoration' that bonuses as a counterweight and living space.

If you're bothered by the shape of an asteroid in a Celestia addon, you can consider asking Steve to create another shipyard model with less spherical asteroid. As for me, I think I'll just leave it like that.

2) Because they are both low mass rubble piles rotating very quickly for their sizes. While Ryugu is larger and rotates slower than Bennu, it is still enough for mass to move to the equator and pile up into the ridge that gives these asteroids their shape.

3) Mass. Small asteroid moons are not in hydrostatic equilibrium and cannot reshape themselves under their own gravity into a spheroid or ellipsoidal shape. Bodies can be in equilibrium and then later be knocked out of round by impacts (Phoebe, Vesta) and bodies not in equilibrium can be quasi-spherical (Iapetus).

A small asteroidal moon in a close orbit around a much larger primary, as appears to be the case for New Eureka and Archimedes, would be tidally locked, with its long axis pointing at its primary. Unless Archimedes orbits New Eureka very quickly and has similar compositional features to Ryugu and Bennu, it is unlikely to be round for the same reason they are.

3) This is plausible and something that I had considered, I just didn't know if that is what you intended.

I have no objection to the current picture. You answered my question to my satisfaction by demonstrating that Archimedes is not spherical, it was just an artifact of the viewing angle. I was just trying to point out that it would be unlikely to be spherical for the same reason that Ryugu and Bennu are.
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#9
Asteroids smaller than 100 metres will often rotate fast enough to have negative gravity at the surface, so many of them will be single rocks rather than rubble piles. This will make small asteroids quite problematic to mine, unless they are de-spun beforehand.
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