If the moon grew 20 percent, and everything else stayed te same, how would the change affect us? I am guessing the tides would act up, but would we lose New Orleans? Manhattan? Would aquatic life be affected? Anything else I am missing?
Measuring what? 20% more mass or 20% larger diameter making it 72.8% more mass?
Weird tides, at least.
Earthquakes. Tsunamis. Cats and dogs living together. Real biblical stuff.
Mosquitos the size of Buicks.
I don’t care about the apocalyptic effect of a bigger moon.
I wanna know how the moon can gain weight!
Eating between meals? Stop exercising? Snarfing comets and asteroids? Obviously, the Earth hasn’t contributed enough by leaving space junk on the moon.
Hmmm?
~VOW
Great. We just turned the Moon into a hoarder. Eventually it will die, crushed as it tries to get into a new orbit by gigatonnes of old newspapers; boosters; phone books; bags of weevilly flour dated 1964; cans of cat food; books; civil-defence manuals; pizza cartons; fuel tanks; and (horribly) flattened, desiccated corpses of Selenians.
Well, it would ruin eclipses for one.
If the moon is going to gain any mass, that mass has to come from somewhere. It can’t just materialize there. Something with 20% of the mass of the Moon wandering around in the Earth-Moon system is probably going to cause some problems even before it gets to the moon. It’s even worse if it’s 72.8% of the mass of the Moon, of course.
The largest asteroid in the Solar System, Ceres, isn’t big enough to do the job. Its mass is about 1% the mass of the Moon. The total mass of the asteroid belt is estimated to be about 4% the mass of the Moon (yes, Ceres does account for a substantial fraction of the mass of the asteroid belt all by itself). There aren’t enough asteroids to increase the Moon’s mass that much.
To increase the mass of the moon by 72.8%, or even 20%, you’d have to drag stuff in from the outer solar system. That would probably have some interesting effects on the asteroid belt, and it’s likely that one or more kilometer-sized or greater asteroids would hit the Earth as a result. That’s going to have more effect than making us lose New Orleans or Manhattan.
If everything else stays the same, then by definition, there will be no changes.
Just needing to level up in nitpickery.
I think he meant everything except for the stuff that doesn’t.
It would have to drastically affect the moon’s speed and orbit. It would either fly out into space or crash into us. The former would be disastrous; the latter would solve all our problems.
If you crash something with 20% of the mass of the Moon into the moon, it’s going to throw chunks off. Some of those chunks are probably going to end up headed our way. That’s going to cause some serious disruption of life on Earth.
All I got is that werewolves would shed 20% more and the wives would be 20% bitchier once a month.
My guess is it would somehow effect Easter eggs too, but I’m not sure how.
So what would happen if the Moon suddenly massed 20% more for no reason discernible to humans?
Humans would have no worries at all.
To achieve 20% greater mass, that probably means the Earth blew up.
~VOW
I may be wrong, but I think this is on the track the OP means. He wasn’t asking what would happen if it got larger, but what would be different if it was larger, and always was that way. I think there is a lot of pedantry going on here.
Just FTW, since this is the second time I’ve seen the term in the last couple days, a ‘supermoon’ is when the moon, due to being at its closest approach to Earth, appears larger than normal (closer to 15% than 20% however), so I suspect it’s not mass that’s being talked about but the diameter or the surface area of the apparent disk. (And my brain is swimming just trying to figure out how to figure out how each of the three qualities is effected by each of the others increasing…this is depressing…I used to be good at math.)
I agree with you. Also, he never asked how it could happen or why. He is just looking for what would happen physically to the Earth and it’s inhabitants.
When the radius or diameter goes up by a factor of k the surface area and visible disk go up by a factor of k[sup]2[\sup] and the volume (and holding density constant) mass go up by a factor of k[sup]3[\sup]. I’d assume brightness goes up like area.