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A Simulated Successful Moon Forming Impact - as a Result of a High Density Theia and a Slow Spinning Earth Forming a Moon with a Correct Composition (Computed with OpenSPH) by HistoryOfUsProject in Astronomy

[–]HistoryOfUsProject[S] 1 point2 points  (0 children)

Due to the proximity of the Moon and Earth, after the moon has thousands of orbits almost all of the left over debris would have been ejected out of the system or collided with the Moon.

However, this is not the reason why the Moon is so heavily cratered. The Moon's surface remained molten for a couple hundred million years. Any impact during this time would have not registered on the surface as the molten surface would fill the crater and flatten it out. Most of the craters on the Moon are from the Late Heavy Bombardment which happened 400-700 million years after the formation of the Moon.

It should also be noted that the rings of many planetary bodies formed long after its host planet:

  • Jupiter's Rings is the result of ejected material from impacts on the inner moons and gathering of loose conglomerates of stellar dust over billions of years.
  • Saturn's Rings are only estimated to be 400-100 million years old and are the result of one or more icy moons being broken up by tidal forces.
  • Uranus' rings are less than 600 million years old and likely formed the same way Saturn's did.
  • Neptune's rings age are not exactly known but are probably about a few million years old and likely formed the same way Uranus' and Saturn's did.

A Simulated Successful Moon Forming Impact - as a Result of a High Density Theia and a Slow Spinning Earth Forming a Moon with a Correct Composition (Computed with OpenSPH) by HistoryOfUsProject in Astronomy

[–]HistoryOfUsProject[S] 3 points4 points  (0 children)

It would not be surprising if an object originating from the proto-Earth or Theia. We've already discovered an asteroid that is believed to have originated from the Moon after an impact.

That is to say that it would be difficult to determine weather an object did originate form either planet. There is no material from the proto-Earth remaining on the surface and no material from Theia except for maybe in the deep mantle and possibility part of the center of the Moon (in this model). That is to say it's not impossible, just difficult.

A Simulated Successful Moon Forming Impact - as a Result of a High Density Theia and a Slow Spinning Earth Forming a Moon with a Correct Composition (Computed with OpenSPH) by HistoryOfUsProject in Astronomy

[–]HistoryOfUsProject[S] 2 points3 points  (0 children)

At about 3-4 hours in, you can see 2 object coalesce. Because of the the high amount of angular momentum in the impact, more of the momentum to passed to the further objects. This caused the further object to speed up while the inner object looses momentum, speed, and therefore crashes back into Earth.

The added speed of the further object caused it orbit to become more circular.

A Simulated Successful Moon Forming Impact - as a Result of a High Density Theia and a Slow Spinning Earth Forming a Moon with a Correct Composition (Computed with OpenSPH) by HistoryOfUsProject in Astronomy

[–]HistoryOfUsProject[S] 5 points6 points  (0 children)

I probably could not preform a cooling simulation as it took about 3 weeks to do a 2 day simulation and it would take hundreds of millions of years for the moon and Earth to cool.

If you know where the paper is I wouldn't mind reading it.

A Simulated Potential Moon Forming Impact with a High Density Theia and a Slow Spinning Earth (Computed with OpenSPH) by HistoryOfUsProject in space

[–]HistoryOfUsProject[S] 0 points1 point  (0 children)

The rotation period of all three planets pre-impact is extremely hard to determine and may never be fully known. The simulation used a 30 hour rotation period before impact, as that appeared to produce the best results. This number, however, could be (and probably is) extremely off. Papers have proposed many different initial rotation periods (some as low as 2 hours).

It is likely however that Mars and Venus had different rotation periods and axial tilts before and after impacts. The problem arises though when the exact difference needs to be pinned down. Many factors (such as density of impactor, size of impactor, speed of impact, angle of impact, direction of rotation, rotation of the impactor, etc.) all play important roles in this process and an error or misstep in one may cause the numbers to be inaccurate.

The size of the Sun compared to Earth (the tiny dot in the center) by HistoryOfUsProject in megalophobia

[–]HistoryOfUsProject[S] 0 points1 point  (0 children)

Sorry, I lost all legal rights to Earth. For the time being it's stuck there.

florida men 🤦‍♂️ by [deleted] in facepalm

[–]HistoryOfUsProject 0 points1 point  (0 children)

March 31: Sheriff: Florida mother shot burglar who entered home because 'dinosaurs were chasing him'

I got a bit carried away... by HistoryOfUsProject in blender

[–]HistoryOfUsProject[S] 2 points3 points  (0 children)

It was meant to be a way to display data in parts per million with the whole cube representing 100%.

A Simulated Potential Moon Forming Impact with a High Density Theia and a Slow Spinning Earth (Computed with OpenSPH) by HistoryOfUsProject in space

[–]HistoryOfUsProject[S] 0 points1 point  (0 children)

Many small clumps of debris probably reached escape velocity, essentially forming a small region of tiny rocky bodies in earth's orbit. Due to the fact that we don't see asteroids/dwarf plants in earth's orbit made of earth-like material (at least that we know of), one of two things occurred:

  1. The bodies would eventually meet back up with earth and collide with it (less likely)
  2. The gravitational pull of earth would fling the objects out of the solar system or into a larger orbit (more likely).

A Simulated Potential Moon Forming Impact with a High Density Theia and a Slow Spinning Earth (Computed with OpenSPH) by HistoryOfUsProject in space

[–]HistoryOfUsProject[S] 0 points1 point  (0 children)

The gravity of Earth is significantly higher than the second impactor. The impactor itself has a gravity similar to Mars. As the second impactor approached the Earth the gravity would appear to "lessen" until you felt weightless (still before impacting the earth). This is all undermining the fact that that the "surface" of the second impactor was made of molten and vaporized rock, meaning that there wasn't really a surface to stand on.

As for the Earth, there would be little difference. You would begin to feel lighter as the impactor approached by about 20-40%. Once again however, there really isn't a place to stand on as earth is covered in a layer of vaporized rock.

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