Slashdot Mirror
Is This Moon Three?
tetrad writes "The BBC reports that a new object has been discovered orbiting Earth. It's possible that it's just a piece of space junk, but more likely it is a rock that has been recently (in the last year) captured by our planet's gravitational field. If the object is confirmed to be natural, this would be Earth's third moon. (Did you know there were two already?)" Here's our earlier mention of Earth's alleged second moon. Update: 09/12 04:52 GMT by T : Reader cscx adds a link to an article running on space.com which says this newfound object may be some trash from the Apollo missions.
Doesnt an orbiting object need to be of some specific minimum size? or does Saturn have billions of moons that just end up looking like rings?
Just out of curiosity, what is the scientific criterion for a moon?
:)
The "trojan asteroid" described in the previous story is only 3 miles wide and take 770 years to orbit the earth. That is not what elementary schoolteachers say is a moon, a la Jupiter's many moons... giants like Europa and IO.
I also heard a while back that Charon might not be a real moon either, because of size or rotation or something? Huh?
I'm not versed in astronomy enough to know, so does anyone have an answer for laypeople, so I can talk with people at work about this?
Space.com
God really is trying to moon us. Maybe we should practice asteroid demolition on these things so we are less likely to screw up if there's one coming straight at us.
Maybe this is just fate's way of teasing us. Quite a bit of talk lately that we are overdue for a deadly asteroid collision. Maybe we are going to be gaining more and more objects locked in our gravitational field, just to make us nervous. Similar to vultures circling overhead.
Excuse me. How many objects are obiting the earth now? Twenty!? I'll be moving to Mars tommorow.
Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
Nasa and I had our hopes of a 4th moon dashed when that NSync kid couldn't cough up the money on time. He hadn't even read the fine print regarding a conditional return.
If you think
...has decided to deploy an advanced warning system, due to the number of missiles coming from Earth that have been hitting or narrowly missing Mars in recent years. While planetary defenses have had a decent intercept rate, some of the missiles are still getting through. Hopefully the new early warning system will enable the Martian Space Defense to improve intercept rates considerably.
Finally! A year of moderation! Ready for 2019?
We all have grown up with the notion that there are three earth-orbiting natural satlites, but did you know that there is no mention of the third satelite in any media before 2002!
It's true!
See, it's all a plot of the Libertarians - they have been secretly construcing this "third moon" in order to live there and to not pay any of their taxes - taxes that you and I need in order to buy delicious governemnt cheese!
Being cheap bastards, this new moon is nesesairly small - but if you look at it with a high-power "telescope", then you'll realise that this "moon" has been meticulously constructed to look like Montanna!
Complete with Moon-Sheep!
I urge you, the right minded American, to rise up and take a stand! No third moon, unless taxes are to be paid on it.
Moneyed corporations, non-working 'poor' and criminal prisoners are turning productive citizens into tax-slaves.
It would be cool to do some scientific experiements on this thing. Maybe even put a "moon 3 cam" or whatever on it.
By the way, I've always wondered- why don't we have a moon cam (maybe we do?)? Or some telescoping equipment on the moon to peer even further into our universe? How hard would it be to put a camera on the moon and have it beam pictures to a nearby satellite or whatever?
Read this and this and have a good laugh. Go Buzz, go !!!
Non-Linux Penguins ?
If you take into account Sun Myung Moon and Keith Moon...
Just because you can mod me down, doesn't mean you're right. Shoes for industry!
I'm missing something. I thought a moon was an object that orbited a planet. Cruithne's orbit is profoundly perturbed by the Earth's gravity, but it stil orbits the sun.
This also happens in Tibet and Southern California.
Hey, see that moon? No that one there. I think that moon is a bit of a spy. Yes I do. There was a moon like that on the summer of my sixteenth year. Some say I was sixteen but [sigh] I don't know. And there was a girl, too; her name was Marie. At night together we would walk down by the sea and oh my god if you could see the body on this woman. The way at night her long legs would stick into the moist night sand like gods own barge poles, you know. And I longed to tell her the feeling I had in my heart for her but the words would not come, they would not come through my spotty adolescent face, they would not come through my angry hair or my sweaty feet or any other part on this body that I know call a man. So the words je t'aime were never passed between us but the moon, yes, that moon spied on us.
Why do we only see news of this on the BBC page? I've not once seen mention of second or third moons on MSNBC, CNN, or any of the other online news places. I'm starting to consider the BBC as the National Enquirer of online news.
To see the data:
Because in SOME frame of reference, the energy of the object doesn't change, this type of elastic collision CANNOT move an object from a bound to an unbound orbit.
It's not wasting time, I'm educating myself.
I hear there's some really good calamari on Cruithne. Some weird blue loop that seems to lead to other universes too, but mainly, good calamari.
If you google for "Cruithne," the name of the second "moon," you'll find that researchers think there are two other objects in strange orbits like Cruithne's. That would make this new discovery the fifth.
Beat that, Jupiter!
Secession is the right of all sentient beings.
Well you're talking complete bullshit too!
If you consider an object of mass m going around the earth at a certain radius r and velocity v the equations are:
Fg=GmM/r^2 and Fr=mv^2/r,
where M is earth's mass and G is the gravitational constant.
for a stable orbit Fg = Fr
-> GmM/r^2 = mv^2/r
simplifies to
-> GM/r^2 = v^2/r
and further
-> v^2 = GM/r
So looking at the final simplified equation for an orbiting body we see that it don't matter shit what the mass of that body is! You only need to have a certain speed to keep it on a steady orbit.
I didn't even think we had one, let alone three!
"Ask not what your country can do for you." --John F. Kennedy
It just so happens that moon's mass does affect the amount of gravitational pull between earth and moon but since the force required to keep a certain mass in an orbit is in the same proportion to mass as gravitational pull (which in this case is the force keeping the moon in orbit) moon's mass get's canceled out.
If you want to further complicate the situation it would be more accurate to say that moon does not orbit earth! In reality moon and earth have elliptical orbits and they both orbit around a point that is somewhere between moon's center and earth's center. So all of the previous talk is just approximation.. If you want to get even more detailed you should take into account relativistic effects too..
Anytime you have something (Foo) orbiting something else (Bar), i.e., once the requirements of "orbit" are met, there are five points of gravitational equilibrium set up amongst the two bodies. They're called LaGrange points. The last two, L4 and L5, are on Foo's orbit around Bar, sixty degrees ahead of Foo (L4) and sixty degrees behind (L5).
L4 and L5 by themselves, ignoring L1-L3, are often called Trojan points, named for this particular group of satellites.
As for the defintion of moon versus just another satellite in general, I believe it has to do with respective mass ratios, and where the fulcrum point of rotation is between the two bodies. Right now our own moon isn't in a true rotation around us, we're in a sort of dumbbell tumble, and the center of the dumbbell is a bit below the ground.
(Actual astronomers please correct me, I'm on a number of narcotic-containing painkillers right now and could have gotten some words tumbled.)
You cannot apply a technological solution to a sociological problem. (Edwards' Law)
If you ever study the 'Trojans', you know that there are huge bodies of apparent moonlets that sit on a sixty-degree angle from Jupiter's, directly along Jupiter's orbit from the sun. (They are apparently held in such a strange place by the gravity of Jupiter vs. the gravity of Sol.)
THis is actually really interesting because it indicates that these are on the L4 and L5 points relative to Jupiter and the Sun. For those that don't know the Lagrange points are the points where the gravity from the orbiting and orbited bodies are equal, and of the five points, only 2 are stable (L4 and L5). This is why, after the Moon, why the L4 and L5 points will be very important politically, economically, and militarily, assuming we want to have commercial relations with Mars...
But this new object is on a 50 day orbit around earth, so it is not on L4 or L5.
LedgerSMB: Open source Accounting/ERP
Since no one knows for sure just what it is, by definition, it is a UFO, an Unidentified Flying Object. That doesn't prove that it's alien, but it could be. If it is a moon, those nasty Zhti Ti Kofft will put a death ray on it.
The Uncoveror: It's the real news.
...why my key policies never get implemented. I hope the newspaper prints a retraction.
And you should see the setups that some of these amateurs have. (And I'm sure that CCD cameras and computers have done a lot to level the playing field when it comes to spotting like comets or sort-of-moon-things.)
And all the money that must be spent by governments? I'm sure a lot of people are rolling on the floor over that remark.
One line blog. I hear that they're called Twitters now.
The music industry is going to ban any mention of multiple moons. For they have thousands of songs that would be obsolete if word got out.
"Moons River"
"Blue Moons"
"Sad Moons Nite"
Etc. Etc. Etc.
"We must protect the integrity and consistency of our content", said an anonymous industry spokesperson. "If you have to force legislation by any means available, we will."
Table-ized A.I.
OK, all together now:
B.G. DeSylva, 1927, from _Good News_, (modified)
The moon belongs to everyone,
The best things in life are three.
The stars belong to everyone,
They gleam there for you and me.
The flowers in spring, the robins that sing,
The moonbeams that shine, they're yours, they're mine.
And love can come to everyone,
The best things in life are three.
Of course, Trinitarians could say
"And God belongs to everyone
The best things in life are Three."
"How to Do Nothing," kids activities, back in print!
Not trying to be nit-picky here but don't moons orbit thier planets in an elliptical pattern, with the planet being at one of the focuses?
But I might be wrong.
You mean that thing that keeps flying around our world without doing anything constructive? It's called a troll.
Hmm, very good one I'd say, take a look at it!
Even if it's man-made, it's still one heck of a job.
Actually, everyone is in fact saying that it's a UFO. One of Earth origin (unless it's natural).
According to NEO, "J002E3 was not a minor planet (Sept. 6.68 UT)". Does this means that they've already confirmed that it's space junk?
Well I woulda thought that too... but where is the centerpoint of Charon's orbit around Pluto? Is it a double-planet? I dunno, you dunno, we dunno, they dunno. But isn't it nice that the terms are so vague we're all right?
Orbits aren't circular, they're elliptical, so it isn't that there's a center, it's that there are two foci, and the planet is at one of them. My question, then, is this: in the case of Pluto and Charon, is Charon at one focus of Pluto's "orbit around" Charon, just as Pluto is at one focus of Charon's orbit around Pluto? And what about the orbits of the Earth and Moon?
Whether or not something is a "moon" is really a function of the language, more than the details of its size, orbital distance, etc. Remember that, at least in English, dictionaries are descriptive, not proscriptive -- that is, they give usages, not definitions. The language changes and evolves on its own; what is considered "correct" is really nothing more than popular opinion. Of course, different ways of communicating can be more or less useful or efficient, so it's not like it doesn't matter whether we use a word to mean one thing or another.
But there's no "official" definition of what a "moon" is, unless you happen to accept the particular definition of a particular person or group. If it's useful to call this 3-mile chunk of rock a "moon," then people probably will. If it's misleading or confusing, then (hopefully) people won't.
"Destroy science and religion. Science would re-emerge exactly the same; but not religion." - Penn Jillette, paraphrased
Luna is a harsh mistress.
Cruithne is a drunken whore.
This little thing is a street urchin that gives blow jobs for crack money.
Not trying to be nit-picky here but don't moons orbit thier planets in an elliptical pattern, with the planet being at one of the focuses?
:)
Well, strictly speaking, planets and moons (and planets and suns) orbit around a common center of gravity. If the mass of one body is much large than the mass of the other, you get pretty close to an elliptical orbit, with the large mass at one focus.
It just depends on how accurate you want to be. For example, Jupiter is large enough that the center of mass of the Jupiter-Sun system is actually outside the photosphere of the Sun, but relative to the distance of Jupiter, that's not much.
One way astronomers look for extrasolar planets is to look for the star to 'wobble' as its planets orbit, so maybe there's a Little Green Astronmer out there somewhere who noticed that little yellow star in quadrant 57 wiggled approximately every 27.3 blurgons, meaning a large planet is orbiting.
A much easier way to make the moon hit the earth is to slow it down, so that it takes up an elliptical transfer orbit with the perihelion underground.
Here, I drew some pictures. The one on the left has its orbit altered drastically, but it still misses the earth. The one on the right is slowed down enough so it falls into the earth; and it didn't need as much of a push.
Patrick Doyle
I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
As for our second alleged moon: it is not a moon!
:b
It orbits the sun in a horseshoe-shaped orbit that goes quite a distance above and below the elliptical plane. The horseshoe orbits overlap, but don't take 770 years. However, because these horseshoe-shaped orbits overlap, Cruithne eventually goes all the way around the sun. It is this that takes 770 years.
It is affected by Earth's gravity (indeed, that is why its orbit is shaped like a horseshoe), but that doesn't make it a satellite of Earth.
Therefore, this "third" moon is actually the second.
I'm quite sure that Luna is the techincal name for the first moon that humans noticed orbiting Earth. Why do I think this? It fits the pattern of the true name of the sun, the other major body that is readibly visible to us earthlings.
:)
"the sun" actually = "sol" (latin in origin, i believe)
"the moon" actually = "luna" (latin in origin, i believe).
It makes sense to me, but then again, I dunno what validity that holds.
Sorry, someone had to say it...
Yes, but from a geocentric viewpoint, the moon's path describes a circle with the earth at the center. From that same POV, Cruithne follows a kind of horseshoe with the sun at the center.
That's not a moon, that's the mothership! Mama, come and get me! I'm ready!
Money for nothing, pix for free
Damn it you beat me to it. Now I'll just grab my towel, some peanuts, drink a few beers and be on my way.
You might have trouble getting change from a fiver though!
"Information wants to be paid"
Scientists think a newly-found object orbiting the Earth could be a remnant from the Apollo era.
Experts at Nasa's Jet Propulsion Laboratory believe its brightness and distance shows it's a rocket booster.
'J002E3' was discovered on September 3 and listed by scientists as a minor planet or asteroid.
But Nasa's Donald Yeomans believes that designation is erroneous.
He told Space.com: "It's most likely a spacecraft. It's not likely to be a natural object, not in that kind of orbit."
He said minor planets or asteroids tend to be on strange orbits gravitationally-influenced by the Sun. This does not appear to be the case with this object.
Nasa are currently running computer calculations and expect to be able to identify the object conclusively soon.
Story filed: 10:39 Thursday 12th September 2002
One line blog. I hear that they're called Twitters now.
If the path of an object is concave with respect to the sun, the object is a planet.
In the case of the Earth/Moon system, it is called a double planet because the path of the moon from the point of view of the sun in strictly concave -- that is it dosn't loop back on itself as do other moons.
I have discovered a truly marvelous sig, unfortunately the sig limit is too small to contain i
Que Luna! Que bella Luna!
I have discovered a truly marvelous sig, unfortunately the sig limit is too small to contain i
Actually, it depends entirely on the amount of mass and means of imparting velocity to the removed mass. If you excavated a lot of mass and decided to eject it from the moon with a mass driver so that the velocity of the moon around the Earth decreased enough, it sure would crash.
I have discovered a truly marvelous sig, unfortunately the sig limit is too small to contain i
After you posted the text I read it again. No mention of j002e2 (or j002e3). The object he found was designated 2002BJ2 . With an aphelion of 3.4 and a period of 1071 days, it is definitely not orbiting the Earth.
Couldn't they take the *spectrum* of the object? That should be able to determine if it is man-made (Apollo left-overs, for example), or a space rock.
Perhaps it is too dim to get a spectrum of. But, if they try hard/long enough eventually you can get a "print" I believe.
Table-ized A.I.