How did Earths Moon come to be?

[Macavity]

 

8 hours ago, LukeSkywatcher said:

Seriously, if this guy is the type of person that Uni's are employing to teach................i worry about future generations.

Scientists are also "people" - Rather surprisingly! (I'm first to admit?!?) lol ?

I am not sure that PUBS are always the best place to make good friends? ?
I remember sitting next to a random guy at the bar. He introduced himself
as the local GP! "We have a lot in common", he said. (Me ex-Physicist etc.)
He started a "tirade" inc. the N-word etc. I slowly moved down the bar.... ?

Scientists are (rather often) GOOD at Science. I am not sure WHY they are
seen as moral / political guides now? Such is the power of "Twitter" etc! ?

[Stub Mandrel]

I like the theory popular when I was a kid that earth developed a 'blob' that gradually span off to form the moon. Requires some spectacularly impossible physics but you get some cute diagrams.

The other one was the 'cigar' of material (drawn out by a passing star?) that condense to form the planets explaining why they are small and the ends and fat in the middle - alledgedly.

And the asteroids are a planet that forgot to form into a lump...

[goodricke1]

Well I wish it had never came to be, it's nothing but a bloody nuisance!!

[DAVE AMENDALL]

According to the Daily Sport ,The wreckage of a Lancaster Bomber has been found on the moon. There must be alternative methods of getting there.??............. Dave

[Stub Mandrel]

3 hours ago, DAVE AMENDALL said:

According to the Daily Sport ,The wreckage of a Lancaster Bomber has been found on the moon. There must be alternative methods of getting there.??............. Dave

They towed it behind the bus that was driven there by Elvis.

[DAVE AMENDALL]

Was that Elvis Costello or Elvis the Pelvis ?

[Stub Mandrel]

23 minutes ago, DAVE AMENDALL said:

Was that Elvis Costello or Elvis the Pelvis ?

Beither? Noth?

(c) Marlon.

[Macavity]

Didn't someone turn up at a fancy dress party... Embarrassed that
they misread "Elvis" .vs. "Elves". Not sure which way though? ?

As a general thought re. such things, I personally I LOVE (admire!)
the various videos NASA (+ others) on produce on such subjects.

https://youtu.be/xvc7Wf1xj4c (Giant impact animation!) ?

Sadly, it seems to work against e.g. NASA? Simulations attract the
plethora of "deniers", who sadly don't understand the basic idea
and worth of such things... It's not intended to be REAL! ?

I'm sure a lot us have / would delight in seeing real Astro events?
But, for a lot of them, at a (considerably) respectful distance! ?

 

[Guest chaz2b]

I suppose people will side with what seems most plausible in their minds, me? I'd just loved to have been in the vacinity if there was a collision , now that would have been a big bang!

Chaz

[LukeSkywatcher]

On 24/08/2018 at 10:38, Macavity said:

 

Scientists are also "people" - Rather surprisingly! (I'm first to admit?!?) lol ?

I am not sure that PUBS are always the best place to make good friends? ?
I remember sitting next to a random guy at the bar. He introduced himself
as the local GP! "We have a lot in common", he said. (Me ex-Physicist etc.)
He started a "tirade" inc. the N-word etc. I slowly moved down the bar.... ?

Scientists are (rather often) GOOD at Science. I am not sure WHY they are
seen as moral / political guides now? Such is the power of "Twitter" etc! ?

I wouldn't call the people I meet in the pub, friends. Some are, but not the Uni faculty. 

[StuartJPP]

On 24/08/2018 at 01:47, LukeSkywatcher said:

He said that the Moon was a planet in its infancy and because it was so close to Earth (4 times bigger), that the Earths gravitational pull "captured" the Moon and stopped it from forming into a planet.

 

And exactly how did the Earth "prevent" the moon from forming into a planet I would have asked him....

 

The moon is the left over junk from the Earth's formation i.e. skip material after Earth was gutted and renovated a few millennia ago.... if it hadn't been ejected the Earth would be just as uninhabitable as all the other rocky planets.

[Stargazer33]

I think the planet that hit proto Earth was Mercury. That's why its mantle is so thin! ???

"It is far better to remain silent and appear a fool than to speak and remove all doubt!" ?

[mikeDnight]

On 23/08/2018 at 09:13, Alan White said:

I rather like the cheese theory myself, but then you cannot beat a nice piece of Wensleydale in my opinion.

On a more serious note, I go with captured remnants of asteroid belt debris, the same material earth was formed or forming from. As to the big impact theory, possible but it does not sit well with me for some reason.

I think its a giant Malteser with the chocolate sucked off. The real mystery is what sucked all the chocolate off?

The scientists like their collision hypothesis but I'm not convinced. It seems simpler and more logical that the earth moon system was born from the same disc of debris rather than by a rogue planet, eventually becoming locked gravitationally, but perhaps that's too simple and logical to warrant continued funding. 

[Littleguy80]

I consulted the brightest minds of the next generation...my children. Their conclusion: “It’s Grannie’s bottom. Full moon... get it? Hahahaha”. 

I’m not saying their theory doesn’t have any holes in it (groan)...

My honest opinion is that the collision theory makes a lot of sense. The chemical composition is a good indicator. We know the moon is continuing to move away from Earth showing a continued momentum from the impact. Remember there’s very little to provide friction and reduce the momentum. If it had simply coalesced and become gravitationally  locked then you would expect the distance between the Earth and the Moon to remain constant. There has to be some force acting on the moon for it to be moving away.

I’m no astrophysicst though so there may well be other ways to explain the expanding gap!

[DiamondSmiles]

This is all very well, but i want to know how the Soup Dragon got to be on the Moon?

[Alan White]

8 hours ago, mikeDnight said:

I think its a giant Malteser with the chocolate sucked off. The real mystery is what sucked all the chocolate off?

The scientists like their collision hypothesis but I'm not convinced. It seems simpler and more logical that the earth moon system was born from the same disc of debris rather than by a rogue planet, eventually becoming locked gravitationally, but perhaps that's too simple and logical to warrant continued funding. 

The chocolate is one of the universes great mysteries Mike ?

Nice to see you have similar thoughts as myself to the debris theory.

Just because the ‘present’ theory is the collision, it will change in time, that’s the things with theories....

[mikeDnight]

57 minutes ago, DiamondSmiles said:

This is all very well, but i want to know how the Soup Dragon got to be on the Moon?

The Soup Dragon never lived on the Moon, because if it did we'd be able to see the Iron Chickens nest in orbit around the moon, and pan lids on craters. From what I seem to remember, the planet of the Clangers was far far away.

 

[Mr Spock]

How did all the other moons in the solar system form? Seems logical they all formed in a similar way. 

[RayD]

4 minutes ago, mikeDnight said:

The Soup Dragon never lived on the Moon, because if it did we'd be able to see the Iron Chickens nest in orbit around the moon, and pan lids on craters. From what I seem to remember, the planet of the Clangers was far far away.

Crikey that brought back some memories.  

A small, blue, moon-like planet.  Awwww I liked the Clangers.

[Gina]

1 hour ago, Mr Spock said:

How did all the other moons in the solar system form? Seems logical they all formed in a similar way. 

That's a very good point.  Seems unlikely that they were all formed by collisions.

[JamesF]

1 hour ago, Mr Spock said:

How did all the other moons in the solar system form? Seems logical they all formed in a similar way. 

I think I'd be tempted to argue that there's no basis to assume they should all form the same way.  Many might form the same way, perhaps by coalescing from of material in a planet's accretion disc, but there's no reason to assume they all would.

James

[Ricochet]

10 hours ago, mikeDnight said:

The scientists like their collision hypothesis but I'm not convinced. It seems simpler and more logical that the earth moon system was born from the same disc of debris rather than by a rogue planet, eventually becoming locked gravitationally, but perhaps that's too simple and logical to warrant continued funding. 

Planet formation is a series of collisions rather than a single event. I don't see how saying one of those collisions resulted in two large bodies instead of one is more complex than saying that two close bodies had their own series of collisions without ever colliding with each other. We're also not talking about a rogue planet flying randomly across the solar system and smashing into Earth, but two in (almost?) the same orbit being gravitationally attracted over time such that they are pulled together and collide. 

37 minutes ago, Mr Spock said:

How did all the other moons in the solar system form? Seems logical they all formed in a similar way. 

There isn't a lot to compare to. The outer planets are so large that they have ring systems in which moon formation can occur much like planetary formation around the sun. Of the other inner rocky planets only Mars has moons and these are so small that they have not even been condensed into spheres by gravity. There is a chance they could be captured asteroids but more likely they are material ejected into space by something colliding with Mars, similar to the formation of our moon on a much smaller scale. 

[Gina]

Our moon situation might be different because the Earth has just one moon whereas the other planets have several/many moons.

[Gina]

Having thought about it a bit more, it seems to me that moons may be produced by all three suggested methods so maybe there is not one common way moons were produced.

[JamesF]

My understanding of what's meant by "chemically similar" is that it doesn't just mean they contain the same sorts of elements, but that there are matches between isotope levels and suchlike that have a low probability of occurring if the two bodies had formed separately.  The greater chance is thought to be that these similarities came about because the Moon and Earth  formed from the same material.

Anyone who wants to (credibly) argue that the Moon did not form from material that was shared with the proto Earth more than likely needs to be able to demonstrate that the observed chemical similarities do in fact have a strong probability of occurring by some other means rather than just sticking their fingers in their ears and singing "La la la, I'm not listening".

James