The ‘Second Moon’ You Didn’t Know Earth Had

By Duncan Forgan, University of St. Andrews | March 2, 2015 2:35 pm

3753 Cruithne

We all know and love the moon. We’re so assured that we only have one that we don’t even give it a specific name. It is the brightest object in the night sky, and amateur astronomers take great delight in mapping its craters and seas. To date, it is the only other heavenly body with human footprints.

What you might not know is that the moon is not the Earth’s only natural satellite. As recently as 1997, we discovered that another body, 3753 Cruithne, is what’s called a quasi-orbital satellite of Earth. This simply means that Cruithne doesn’t loop around the Earth in a nice ellipse in the same way as the moon, or indeed the artificial satellites we loft into orbit. Instead, Cruithne scuttles around the inner solar system in what’s called a “horseshoe” orbit.

Cruithne’s Orbit

To help understand why it’s called a horseshoe orbit, let’s imagine we’re looking down at the solar system, rotating at the same rate as the Earth goes round the sun. From our viewpoint, the Earth looks stationary. A body on a simple horseshoe orbit around the Earth moves toward it, then turns round and moves away. Once it’s moved so far away it’s approaching Earth from the other side, it turns around and moves away again.

Horseshoe orbits are actually quite common for moons in the solar system. Saturn has a couple of moons in this configuration, for instance.

What’s unique about Cruithne is how it wobbles and sways along its horseshoe. If you look at Cruithne’s motion in the solar system, it makes a messy ring around Earth’s orbit, swinging so wide that it comes into the neighborhood of both Venus and Mars. Cruithne orbits the sun about once a year, but it takes nearly 800 years to complete this messy ring shape around the Earth’s orbit.

Cruithne Close Up

So Cruithne is our second moon. What’s it like there? Well, we don’t really know. It’s only about five kilometers across, which is not dissimilar to the dimensions of the comet 67P/Churyumov-Gerasimenko, which is currently playing host to the Rosetta orbiter and the Philae lander.

The surface gravity of 67P is very weak – walking at a spirited pace is probably enough to send you strolling into the wider cosmos. This is why it was so crucial that Philae was able to use its harpoons to tether itself to the surface, and why their failure meant that the lander bounced so far away from its landing site.

Given that Cruithne isn’t much more to us at this point than a few blurry pixels on an image, it’s safe to say that it sits firmly in the middling size range for non-planetary bodies in the solar system, and any human or machine explorers would face similar challenges as Rosetta and Philae did on 67P.

If Cruithne struck the Earth, though, that would be an extinction-level event, similar to what is believed to have occurred at the end of the Cretaceous period. Luckily it’s not going to hit us anytime soon – its orbit is tilted out of the plane of the solar system, and astrophysicists have shown using simulations that while it can come quite close, it is extremely unlikely to hit us. The point where it is predicted to get closest is about 2,750 years away.

Cruithne is expected to undergo a rather close encounter with Venus in about 8,000 years, however. There’s a good chance that that will put paid to our erstwhile spare moon, flinging it out of harm’s way, and out of the Terran family.

Other Moons?

The story doesn’t end there. Like a good foster home, the Earth plays host to many wayward lumps of rock looking for a gravitational well to hang around near. Astronomers have actually detected several other quasi-orbital satellites that belong to the Earth, all here for a little while before caroming on to pastures new.

So what can we learn about the solar system from Cruithne? Quite a lot. Like the many other asteroids and comets, it contains forensic evidence about how the planets were assembled. Its kooky orbit is an ideal testing ground for our understanding of how the solar system evolves under gravity.

As I said before, it wasn’t until the end of the 20th century that we even realized that bodies would enter such weird horseshoe orbits and stay there for such a long time. The fact they do shows us that such
interactions will have occurred while the solar system was forming. Because we think terrestrial planets grow via collisions of bodies of Cruithne-size and above, this is a big new variable.

One day, Cruithne could be a practice site for landing humans on asteroids, and perhaps even mining them for the rare-earth metals our new technologies desperately crave. Most importantly of all, Cruithne teaches us that the solar system isn’t eternal – and by extension, neither are we.

The Conversation

This article was originally published on The Conversation.

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  • Sal Volatile

    Interesting article but I cannot help but to point out that the phrase “the Earth” is incorrect. You definitely would not say “the Mars” or “the Venus;” likewise, the same holds true when communicating about our planet.

    • Mike

      Oh no you didn’t!

    • Allen Bennett

      Just because it’s “Manhattan” doesn’t mean it’s not, “The Bronx.”

      • Sal Volatile

        False equivalency. Try again.

    • jason T.

      actually, while you have and interesting point, you are not correct. ” the Earth” is not incorrect. I just spoke to my wife who is in publishing and she says she has seen it done many ways including ” the Earth.” the main thing is that” Earth” is capitalized so the reader knows your are speaking of the planet and not the dirt under your feet. But by no official stretch is it ” incorrect.”

      • Jason Long

        When using “the earth” in a phrase, it should never be capitalized. “Earth” is the pronoun that distinctly identifies the planet on which we live.

        Just like in billiards, if you’re going to put a little “english” on the cue ball, it must not be capitalized as we are not necessarily talking about the pronoun. (Also, this is the only instance in which you would not capitalize the word ‘English'”.)

        • skip saunders

          “Earth” is a noun, not a pronoun

          • Sal Volatile

            More specifically, it is a proper noun.

        • jason T.

          I would very seriously read your response again cuz it makes no sense. In the first place earth is not a pronoun it is a proper noun in this case because it is the exact name of a person place or thing. Proper nouns not pronouns are used and capitalized for things that have that exact name. Your comparison to putting English on the ball is partly correct but is in direct opposition to the example in the story. The proper name of the planet is the earth therefore it should be capitalized when speaking about the planet. if you are talking about the dirt beneath your feet then it would not be capital because the proper name of that material is not earth it is dirt, soil, etc..
          English is capitalized if we’re speaking of the language but not a phrase thats slang in pool so that part is correct. However the proper name of this planet is earth therefore it is capitalized because it is a proper noun it is the name given to the planet.

          • Diego Hernandez

            “…if you are talking about the dirt beneath your feet then it would not be capital because the proper name of that material is not earth it is dirt, soil, etc..”

            What this guy said. Let’s put a bit of “the English” on the billiards ball.

          • Sal Volatile

            Again, your understanding of the basic rules of English is lacking. “Hey, it is the Jason” sounds just as stupid and is just as incorrect as looking at a map of the solar system and saying “Look here, there is the Mars, the Venus, the Pluto, the Earth.”

          • jason T.

            Sal,
            What are your qualifications other than as a mafia hitman? I agree this is remedial english, a class you obviousky skipped. Might i suggest you retake the course? In the mean time I will school you. Please follow along…

            1) my wife is in publishing and you are not. She has worked for major newspapers and other publications. She has a degree in journalism…she lives to correct stuff. She literally gets paid to do it.
            2
            2) in publishing , there offical guidelines they follow to write stuff. One example is the AP style book. It is one of the “bibles” of the publishing industy. In all these years, I i have learned on real important thing from her; lots of things can be said more than one way and be accepted. While you dont like it, it is not incorrect. Period.

            3) if all else fails let’s look at some grammar. “The” is an article, it is most often used before a noun. Here is the fun part it is also” used to mark a proper noun, natural phenomenon, ship, building, excetera.” I got that right off of google…just look up “the” and see the definition.” Earth is a proper noun.”

            So while you don’t like it…it is correct use of the language. Having an opinion is fine , but you are attempting to insult people when you clearly are an uneducated moron. Save the posts for something you do know about….auto repair perhaps.

          • Sal Volatile

            Jason, I respectfully submit that all the comments you have made here have numerous and glaring grammatical errors; before you talk about “schooling” someone, you had better make sure your mastery of English is up for the test. I will just point out a few as there is no sense in rubbing your nose in it.

            – “actually, while you have and interesting point,”

            Actually, you need to CAPITALIZE the first letter of the first word of a sentence, no exceptions.

            – ” is not incorrect.” Incorrect means “not correct;” literally you are saying “is not not correct,” which is a double negative, which we all know makes a positive.

            – “your response again cuz”

            “Cuz” is not a word.

            – “The proper name of the planet is the earth therefore it should be capitalized when speaking about the planet.”

            Oh, this one is really good. You admit that Earth should be capitalized, yet you don’t capitalize it. I guess you only capitalize it when you speak it. See what I did there or was it whoosh! right over your head?

            – “I agree that “the mars” doesn’t sound too correct,”

            Mars should be capitalized. I was not asking you to agree about how it sounds; I was pointing out that it is absolutely wrong in English, just as “The Jason” would be absolutely wrong. Got it?

            – “What are your qualifications other than as a mafia hitman? I agree this is remedial english, a class you obviousky skipped.”

            Wow, I had hoped that you would have learned something along the way. Calling me a “mafia hitman” would qualify as an ad hominem attack. Make sure you look that up. Yes, all of this is remedial English, a class that I “obviousky” skipped. I could go on and on and on, calling you out on all the other basic grammar, spelling, and punctuation errors, but really, why bother? Your wife is an “expert,” and therefore, by proxy, you are an “expert.” I guess if by wife you mean trans-person and expert you mean at BS, then we are agreed.

            Thank you for providing me with some much needed humor today. Talk to you later, English master.

          • jason T.

            Sal,
            Of course you do, it is the only thing you can possibly get me on since I was correct on the point in question while you were not. Remember the point we were discussing; not the 10 mistakes you tried to dig up in desperation to validate yourself?

            I was right….you were not. Call me on any or all of those points. I don’t remember saying I dont make mistakes, especially when responding to folks like you. I FIGURED IT WAS CLOSER TO YOUR LEVEL SO WE WERE FINE. LOL

            Look, I know little burns like this mean alot to you. It’s a small validation in an otherwise wasted life. So here is another plan that will once again prove you wrong. Contact Discover magazine; in particiular the person who wrote the article. Give him your opinion and school him. If a mistake has been made, they will print a correction. That happens in publishing. If they did indeed make a mistake, they will take the rap for it. I know you will make an excuse for not doing this, once again proving I am correct.

            On a personal note, I am glad I got to you. That whole detailed grammar breakdown of my posts is the classic internet final line when the other person has been bested and has nothing to come back with.

            I was correct. You know it, everyone who saw my post and checked google knows it. Class dismissed sally boy.

          • Sal Volatile

            This one is funny. A completely different writing style than earlier…could this be the Jason’s alleged “wife?” This is hilarious! LMAO! He had to get his wife to write a semi-coherent response to me! I’m literally laughing so hard it hurts!

          • jason T.

            What’s funny is you still have yet to address the actual subject we were discussing or even the challenge to contact Discover.lmao

            I think the more you post these recless comments, the more people see how full of crap you are. I slammed you so hard you literally can’t address the subject at all. Lmfao.

            Oh sal…I guess you don’t learn do you? I love setting morons like you straight. Keep commenting so people can see you have no reponse to the original arguement which you very clearly lost. I love it.

            Also, I have you respoding right away…wow you must be desperate!

          • Sal Volatile

            Oh, you took me to school alright. You, sir, are a moron of the highest order. You defer to your wife as an “expert” and yet she is far from it. Go talk to an actual expert in English before you go flapping your gums. Pathetic.

          • jason T.

            Sal,
            You keep talking without ever saying anything of worth. I suspect this is how you live your entire life.
            Once again you insult rather than address the subject that started all this. You challenge opinions and offer no proof. Whom should my wife talk to? What is she wrong about exactly. Spell it out please.

            The sad thing here is your a fool and a supreme idiot.you lost the battle on the subject that started all this (“the Earth” comment) and now rather than accepting it, you just keep going.

            Seek some help.You are a fool sir: you challenge opinions with nothing to back them up, you mud sling to cover your failures.
            Sal, I will never grow tired of saying this: you were WRONG. Everyone who reads this knows it and all the covering in the world can’t hide it. Bet that hurts.

            Contact Discovrr like I suggested. Prove me wrong. You can’t and all you have left is to act like a D-bag and pretend it never mattered. Fyi : you are a terrible ctor.

          • jason T.

            You lost sally boy. Even your verbose and circular replys are getting shorter and increasingly simplistic in their content.
            I will continue as long as you like, but it’s over and you know it.
            You are just too much fun for me to stop! Lmfao

          • jason T.

            Sal,
            I feel any responsible spouse would post the following since you brought it up

            On the subject of my wife’s expertise I submit the following:
            she has worked in publishing for 20 years. Everything from newspapers to magazines. This industry is what I refer to as a performance-based one. What I mean by that is your performance is an absolute must in order to continue to be employed. Much like a doctor or an engineer, she has to perform daily tasks based on knowledge and do them in a more than adequate fashion. The short end of this explanation is she’s good… very good and she has to prove it every day or look for another job. So her expertise is not really in question here, If it were then one could say she would be high up in the strata. There is always someone better or smarter, as is evidenced by you running into me today Sal.
            The fact remains your challenge to my wife’s expertise is without basis or foundation of any kind. it is similar to any layperson challenging a doctor’s medical opinion when that person has only a highschool education such as yourself Sal.
            My wife’s expertise is such that she has received many awards not only for excellence, but for indeed catching mistakes that other people have made that would have cost the publication trouble if it made it out in the articles.
            Once again Sal ,your wrong on something. I would think you would get tired of it by now.

          • Sal Volatile

            Aw, I must have really gotten inside your head for you to have made these emotional responses over and over again. And for your wife to start writing your responses shows how much control I have over both of you. It is splendidly pathetic.

          • jason T.

            Lmfao! Sal, is that really all you have left? I said I got to you and you say it back????

            You lost Sal. You were dead wrong about “the Earth” being incorrect. I keep mentioning this because you jeep avoiding it. You lost and not once have you even casually mentioned it again. I have a feeling the pathetic behavior is all yours my mentally challenged friend.
            I know you hate this, but I am stating facts. These facts destroy your case , so you mudsling.
            As for control, i Iseem to have all of it. Much like dealing with a dumb dog, so long as I post…I know you will respond. I have you as long as I want this to go on.
            You were dead wrong. Learn to love it because every post will continue to mention it. You are truly incapable of stopping huh? I really have you going.

            P.S. i love the dime store psychology. It must come in handy at the auto shop. :-)

          • jason T.

            Lmao! Sal, is that really the best you can do?? I said I got to you and you repeat it back? I think you just cornered the market on being pathetic.
            You were wrong about “the Earth” plain and simple. Since I offered proof, you have tried to avoid the subject. You claimed to have superior English skills and failed.

            As far as control goes, it is all on my side. I know if I post you will always reply, with a declining level of intellectual response. I have you until I am done with you.
            here is an interesting twist I hope you enjoy it:
            if the next post you submit does not offer a rebuttal to the original argument, I will consider the matter closed and that you admit defeat. We can continue to mud sling until I wear you down, but if you fail to address the original issue ,you lose and unconditionally admit defeat. Any excuse you make will wind up doing the same thing as well.
            This should be fun cause we all know your response will avoid the subject entirely…lol.

          • Sal Volatile

            Let us say you had a friend from Mars. He doesn’t know a lot of English but he is learning and you are helping him. He comes over and you are showing him a map of the solar system and you point out his planet and say, “Mars.” Then you point to Earth and say what: “The Earth” or simply “Earth?”

            Remember, he does not know a lot of English and has no idea how a word like “the” can function in English. If you tell him “The Earth,” he might easily come to believe that the word “the” is really a part of the name, and henceforth and forever mistakenly refer to Earth as “The Earth.”

            Now, our little Martian friend goes back to Mars, with his solar system map and shows all his friends. When he points to their own planet, they all know it to be “Mars,” and when he points to Earth, they all say “The Earth,” just like you taught him.

            This is a serious response to your challenge. Please take the time to read and think about what I wrote. If you feel that my argument and example is somehow flawed, please point it out to me.

          • jason T.

            Sal,
            I do appreciate the serious response. Please allow me ro respond
            Your example is overly simplistic. That was not an insult. Let’s look at the facts:
            “The” is an article. It can be used to mark a proper noun. That is the rule plain and simple. Now, is that rule always universal…no. i agreed with your earlier point that ” the Mars” sounded wrong. However, that does in no way negates it being used to refer to Earth. Not at all. Worst case senatio, ” the Earth” is the exception to that rule.The English language is full of exceptions like that. If you can find actual oroof this is incorrect olease present it here.

            Sal, all things aside you are entitled to your “opinion.” That does not mean you are correct.

            Take my suggestion and bring this to the attention of Discover. If your point is accurate they will print a correction. Have all the opinions you want; they did not make a mistake using “the Earth” as they did.

            All I ask is that you present actual proof in future posts. I cited the exact grammar rules used, not an example I made up myself. With respect this time….you are not correct here. I dont mean to slam you, but you are wrong. It is proper to use the term “the Earth.”

            If you still have issue bring some proof to the table, bot more self generated examples. We have worn that out. We could also let it go and let the proof if both sides stand as is. Your choice.

          • Sal Volatile

            I studied under a professor who has been writing textbooks about Earth since the 1960s. He is what you would call an expert in his field. If you read any of his textbooks, you would see he makes a point to refer to our planet simply as “Earth.” In fact, if you happen to take one of his courses, he will specifically point out that using “the Earth” when referring to the planet as a whole is wrong.

            Your argument is based on an ambiguous exception to the rule. If you were to attempt to explain that exception you would see that there is no logic behind it; in fact, it is a contradiction of the rules. The best explanation that anyone can come up with is “well, just because…” If you have a better explanation for this exception, by all means, share it.

            Your given name is Jason. It would be grammatically incorrect for you to be referred to as “the Jason.” This is a fact that follows the from rules of grammar. Do you disagree?

            Likewise, the current agreed upon name of our planet, at least among English speaking people, is Earth. Therefore, it is just as grammatically incorrect to say “the Earth” when talking about Earth as a whole. Using “the Earth” contradicts the rule we established in the previous example. I know you agree to this because you stated it was an “exception to the rule.”

            “The” is a definite article, used to denote something specifically. The red car, as opposed to a red car (“a” is an indefinite article.) If you said “The earth beneath my feet was soft and spongy,” the reader or listener would understand that you were referring to a very specific part of this planet and not to the whole. Agreed?

            Your name, “Jason,” already designates you as someone specific; that is why no one would ever say “the Jason.” “Mars” designates a specific planet; likewise, it would be against the rules of grammar to say “the Mars.” Do you agree? Then, logically, it follows that “Earth” is what we should call this planet, not “the Earth.”

            You are asking for proof that my assertion is correct. I have laid out a logically sound and valid argument to support my case by use of analogy as well as pointing out contradictions to the specific grammar rule. I have also made an appeal to authority by bringing my former professor into this.

            Now it is your turn. You have already acknowledged the exception to the rule, which means you admit there is a contradiction. Your job now is to address the logic of my argument by any valid means you see fit. However, declaring my thesis too simplistic is not a valid critique, unless you can show specifically how it is so.

          • jason T.

            Sal,
            I see no proof here whatsoever. You merely expanded your story telling to an impressive level. Let’s examine this:
            So you studied under a professor who is an expert in surprisingly , books about the Earth. Ok you win. You out did me. Lol. I just have a few questions. If this were true, why has it not made an appearance anywhere in your arguement until now? Also it is so very anazing you know an expert on the exact subject. Further , is his expertise in geophysics,geology or English? Further, in the 1960’s Pluto was a planet, but not any more. Things change.
            Forget all that for a second. In all the validating of your expert, i failed to see his or her name or the titles of any of the books written by this person. Can you provide this info please? Till you do it is just your word and opinion. When i asked for facts i meant verifiable facts. We need to be able to see in writing that you are correct. Sal, I see alot of me in you. If i had this type of confirmation, it would of come out right away to shut uou down. I believe there is no such person, but please provide their identity and some oublucations they have written. I will read it for myself.
            Also, i never said it was an exception; i said at worst it could be. The simple fact is your examples are horrible and just bad choices period. Notice i have avoided exact comparisons because it is easy to make a mistake and think you are right. Find something verifiable that says “the Earth” is incorrect. I asked my wife who is very good at what she does and she cleared it. Side note: that would of been a good time to pull this expert you now have. Why didn’t you? Anyway, you didnt like her opinion so i went on google and found oroof. “The” is an article used to mark a proper noun. Earth is a proper noun and applies to the situation. I cant tell you why it doesn’t work for Mars”, but neither can you.
            Sal, you keep reposting the same responses no matter what. Find an exact rule of grammar or publication that states WHY “the Earth” is incorrect. This last post of yours offers no proof, it is merely your opinion. Show exact proof why it is wrong and no more examples of Mars and Jason. If it is truly inncorrect, then there will be a grammar rule you can cite to show this. Also post this professors name. Who ever they are, you seemed to play them up as famous so releasing their name won’t be an issue of any kind.
            I am giving you every chance here to prove your point. Let’s see some real facts Sal. Bo more fuzzy exampkes.truth is you dont have proof and sumply can’t concede.

          • jason T.

            “If you were to attempt to explain that exception you would see that there is no logic behind it; in fact, it is a contradiction of the rules”

            Uh huh. Sal, are you not familiar with what an “exceptuon” is? I cited a rule to explain its use. You can’t explain why it doesn’t work other than comparing more proper nouns and mysterious experts. Find the exact reason “the Earth” is not logical and wrong. So far you have just provided your opinion. If it is indeed an exceptuon, then all your current examples are worthless. The point is it works. Get proof it doesn’t. PROOF.

          • Sal Volatile

            Answer this simple question: Is it grammatically correct to say “the Jason?”

          • jason T.

            Sal,

            Avoiding the question once again lol if indeed “the Earth” is an exceptional use of the rule, it still works. It works independent of all these useless examples you provide.

            Sal, produce the name of your professor, a few of his titles or the exact rule of grammar that negates the use of ” the Earth” or go home! Lmfao

            All you keep posting is your opinion! Regardless of whether “the Jason” is right or wrong, it has no bearing on The Earth! Lmao. Tyou fail to understand that.
            Your arguement went from Experts you studied under to answer this bad example. Lol.

            Validate your expert if you can. I doubt it can be done. Otherwise you would of by now. Just let this go Sal. You have yet to provide factual proof.

          • Sal Volatile

            An argument by analogy “takes note of the fact that two or more things are similar in some respects and concludes that they are probably also similar in some further respect.”

            If we officially renamed the planet “Gaia,” would you refer to it as “the Gaia?”

            If you moved to Mars, would you refer to it as “the Mars?”

            Why don’t we ever hear “the Virginia?” Or “the North Dakota?” What about “the New York City?” Or “the Barack Obama?”

          • jason T.

            Sal,
            I thought we agreed no more bad analogies here lol You keep missing the mark here intentionally.

            I will reference Dr. Reed Wicander who you listed in a previous post was your professor.
            You can keep coming up with useless “what if” scenarios or just quote the exact rules that make “the Earth” incorrect. I can see you don’t have such an argument as your comparison examples have taken us from a martian visit to earth to learn English to renaming the planet..lol Just stick to verifiable facts not stories.

            On that note, I have some new evidence for the subject. While you were correct in your “under-informed” point that saying something like “the Mars” was wrong, you missed a few things. We see ( and say) “the Sun and the Moon.” All of those are correct English. It would seem this is not a sole exception to anything and why is is correct to say those and leave Earth out? Sal , no opinions , quote some grammar here! Tell me why EXACTLY.

            Let me run a head of you further: I posed the question to an English Teacher just less than an hour ago. She told me it is for the same reason we don’t say “carefullier” we say “more carefully.” that was just an example she used ,, but essentially it’s just the way our language is structured. the use of the definite article “the” to mark a proper noun is used in some places and not needed in others.

            Sal, the only thing I ever said was using “the Earth” was not wrong.. You fail to submit to this because you are stubborn. I ask for proof and you come up with stories from your head. I will continue this banter with you for as long as needed, but each time you don’t post actual proof from the rules of grammar , you just waste your time. We all know you believe you are right. What we need is some proof.

            If you continue to post examples like you have been, we will all be forced to realize that you just gave up on this. your opinion only matters here is you can back it up with generally accepted proof. I will look into your professor, but if he can’t provide proof then I am afraid you’re done.

          • jason T.

            sal,
            I found your professor and one of his books :Historical Geology.” I have been skimming the book online and have found several spots where he uses ” the Earth” in a sentence just like the Discover article did. In fact when you go back through the article, you will see they use both your form and my form all over. If you reread carefully you will see that each is appropriate in its setting in the sentence. the only thing I ever said is that you were wrong in saying “the Earth” was an incorrect way saying things. In truth, they used all of the variations correctly when it called for it..

            Tour own alleged mentor even uses it in his text. I would say game over. Even if your professor hated using the term ” the Earth”, it does not mean it is wrong to do so. All it means is that is his preference. “the Sun and The Moon” are used just as often and they are correct as well.

            Sal…it’s over. You can generate more comparisons if you wish, but they have all been proven wrong already. Even your own expert used it my way! To me it would seem that both forms are acceptable depending on what you are trying to say. what is incorrect is your point that “the Earth” is not a proper term at all.

            Now, if you want to waste more time we can. I think this just got wrapped up and the last thing we need are more crazy examples that only show your lack of understanding of this matter.

          • Sal Volatile

            Oh boy. There is no arguing with you. The fact is, you have proven nothing wrong. Do you understand how logic works? First of all, this is not deductive logic, where you can “prove” something. There are no English “proofs” as there are mathematical proofs. How do you expect to argue with someone when you do not even understand the basic rules under which you are arguing? Every comment you have responded with is full of logical fallacies, not to mention the glaring grammatical errors.

            Never argue with an idiot; he will bring you down to his level and beat you with experience. You win,hands down. Good luck because you are not going to make it on wits alone.

          • jason T.

            Sal!
            That was utterly pathetic! lol I have done nothing but present facts against your made up examples.
            This is a question of proper and correctly used grammar; You keep citing logic as if that trumps all. Your arguments are very logical and laid out; however, they completely ignore the rules of grammar.Therefore they are flawed. Logic is no the answer , it is a way to effectively get to the answer.

            You don’t have a single clue about any of this. I have:
            -provided the exact definitions of the grammar rules I used to explain my point
            – consulted people who are in the fields of English and Journalism
            – Provided other similar examples a (” the Sun and the Moon” and asked you to provide proof against them. You didn’t
            -I located your “expert” who says you are right and he even uses “the Earth” in his book.

            I have proven factual information to support my case at every turn. what your enraged about is that I have undone all your crazy stories and false experts..lol

            Sal your an idiot and you ARE WRONG. I have laid out tons of proof and all you can say is that I lack logic. Great, while I lack logic(according to you) I have the answer to this issue and many more. lol

            Since you are the idiot here, I shouldn’t argue with you ( according to your last post). You lost and there is no proof you can submit to prove otherwise.

            The truly sad thing is that if you would just take a little direction , you might be something more than this. when I hit you with facts you just run and revert to general insults against me. You can’t even debate a point that you profess to be an expert in.

            Live with it. come back with some more insults… it’s all you have. BTW I know your type; you have to respond again. You will come back with more insults, made up examples, etc. ANYTHING but the grammatical rule to prove me wrong, the official reason your mentor uses the phrase “the Earth”, etc. You live to argue…. not debate a subject intelligently.

          • jason T.

            Sal,
            I accept you think you are right. I have seen you flat out ignore facts here. While this is not math, Englishbhas some pretty clear cut rules to use. I am sorry that you are not satisfied by them, but again your opinion is yours to keep any way you wish.

            what it is not is fact.

            I am willing to just let things lie as is. Let all the posts stand with all the evidence I provided and let people sort it out themselves. You made a mistake and now won’t admit to it because of pride. I too am stubborn and presenting hard facts while you turn them down simply because you want to serves no one.

            If you don’t reply, then I won’t either and we can consider this closed. No winners, no losers just the argument as documented for all to see and make up their own minds,

            No need to agree to the terms by responding to this. I won’t keep it going if you won’t. Seems logical to me.

          • jason T.

            Sal. I see my final post did not make into the conversation so I will re-post it now.
            II am sorry you can’t grasp this simple concept. Truly, it would be nice if you were able to learn from your mistakes. I outlined ,l outlined CLEARLY that “The” is a definite article used to mark a proper noun. The definition never said it was applicable every where. Neither did I. I explained this to you, offered my wife’s opinion as she working in publishing, etc. You ignored it. You somehow came up with a “real” expert to back you up. I found him and saw that he too used “the Earth” in one of his books. this shut down your only attempt at verifiable proof.
            Your sole argument was ” can you say the Mars or the Jason?” This very comparison underlies the assertion that since you can’t say the Mars, you can’t say The Earth either. You denied this but it is true. You logic was flawed and to date, this is the only real argument you have made. Numerous times I asked for verifiable proof and you were unable to respond as instructed.

            I think you are the one who doesn’t understand the subject and refuses to acknowledge it. Further, you can’t even come up with a rule of grammar that negates my point. all you can do is make horrible analogies that don’t make a solid point.
            Better luck in the future man

          • jason T.

            Sal. I see my final post did not make into the conversation so I will re-post it now.
            II am sorry you can’t grasp this simple concept. Truly, it would be nice if you were able to learn from your mistakes. I outlined ,l outlined CLEARLY that “The” is a definite article used to mark a proper noun. The definition never said it was applicable every where. Neither did I. I explained this to you, offered my wife’s opinion as she working in publishing, etc. You ignored it. You somehow came up with a “real” expert to back you up. I found him and saw that he too used “the Earth” in one of his books. this shut down your only attempt at verifiable proof.
            Your sole argument was ” can you say the Mars or the Jason?” This very comparison underlies the assertion that since you can’t say the Mars, you can’t say The Earth either. You denied this but it is true. You logic was flawed and to date, this is the only real argument you have made. Numerous times I asked for verifiable proof and you were unable to respond as instructed.

            I think you are the one who doesn’t understand the subject and refuses to acknowledge it. Further, you can’t even come up with a rule of grammar that negates my point. all you can do is make horrible analogies that don’t make a solid point.
            Better luck in the future man

          • jason T.

            This is such a bad example! Not every proper noun has to be or even functions properly with “the” preceding it. No one ever said it did. Where you are losing this argument is your assertion that since you can’t say “The Mars” you can’t say “the Earth” as well. Not even close to true. “the Sun,TheEarth, the Moon” all perfectly correct. “the Jason,the Mars” don’t work.

            As you can see, some forms work and some don’t. Thant was never the argument here. You said it was not correct grammar to say “the Earth”. this is not at all true. Then you claim no experts are needed to validate this; how convenient for you..lol the fact is you’re wrong, and there is proof on Google as well as from several experts I have consulted. Sal you were wrong and now you want to delete posts to revise your poorly structured argument. I guess I got to you a little more than I thought I did.

          • jason T.

            Sal,
            think about this for second. Following your example leaves one with the conclusion that no proper nouns work with “the”. look at how you structured it your entire argument now comes down to whether or not ‘the jason” is it correct or not. the implication of that statement is that if “the jason” is incorrect then so is” the earth.” the underlying point you are making without realizing it is that you took one random proper noun and said that since it was incorrect all the other proper nouns can’t use the and we know that is not true. it was a bad example on your part, stop using it and please post your professor’s name, some of his work and /or the grammar rule that negates my former argument.

          • Sal Volatile

            Actually, I am demonstrating unequivocally that there are some proper nouns that are never used with “the.” I never once asserted that no proper nouns work with “the.”

            Look up Dr. Reed Wicander.

          • jason T.

            “If you were to attempt to explain that exception you would see that there is no logic behind it; in fact, it is a contradiction of the rules”

            Uh huh. Sal, are you not familiar with what an “exceptuon” is? I cited a rule to explain its use. You can’t explain why it doesn’t work other than comparing more proper nouns and mysterious experts. Find the exact reason “the Earth” is not logical and wrong. So far you have just provided your opinion. If it is indeed an exceptuon, then all your current examples are worthless. The point is it works. Get proof it doesn’t. PROOF.

            Think of this: perhaps an article is not needed ) or even properly functional ) with all proper nouns. That being the case, it would work with some , but not really with others. So “the Earth” works and The Mars” doesn’t.” What also works is “the Sun and the Moon.” All of these work perfectly. when it comes to using “the Jason” it would seem it is not needed. It comes back to the point that using “the” before Earth is not wrong. It will certainly not work for EVERY proper noun but no one ever said it had to. Also, the article uses “the Earth” and “Earth” when needed. Even your professor/expert does the same thing in his books. Also look online at thousands of articles written that are doing the same thing.

            I checked out your expert and even he used “the Earth” in his book! it would seem you are the only one making this point and have no backing whatsoever.

          • jason T.

            Test test

          • jason T.

            Sal,
            had to switch modes for a sec. Let’s try this.
            You have avoided the subject a long time now. It would seem all you can do is mudsling ( and you are not even good at that). So how about you address the issue and prove me wrong? You can’t do that because you were wrong.

            Address the original issue (“the Earth” comment) or just stop embarassing yourself. If you respond with any comments other than those addressing the original subject , we will all know you were utterly wrong and have no recourse to correct that.

            Thanks for playing.I loved getting to like this.

          • jason T.

            Sal,
            Sorry, I only skimmed your vain and childish reponse before replying. You in no way mentioned the whole “the Earth” comment that is the basis of this entire arguement.

            It must really have hurt that you were so off base ;you didnt even mention it and tried to grasp at any other small point that you thought would let you insult me. Wow. Your wife has my pity, she must be a saint to deal with someone who will try to be right at any cost and never admit a mistake.

            Contact Discover. If you were correct I would of admitted it. Stop being a child and be half the man you pretend to be. Googling terms you know nothing about to appear smarter than you are is sad sally boy. Just sad.

            P.S. I never claimed to be a master of English; by proxy or otherwise.My wife has more education in that field than you or I do. I asked her, she gave me the answer, it was later validated by google. The rest is your arrogant imagination. You went over the top, you appointed yourself the master and set off to insult me. I responded in kind and proved you wrong. This is your doing and now you have been shown your error. Learn from it as we all do.

          • Sal Volatile

            Your English and reading comprehension skills are an absolute joke. You are not doing yourself any favors by spouting off about a subject you are entirely inept at. You have my pity.

          • jason T.

            Sal,
            I couldn’resist correcting your mistakes on the assessment of my mistakes:

            ” is not incorrect.” Incorrect means “not correct;” literally you are saying “is not not correct,” which is a double negative, which we all know makes a positive.

            -while using the double negative can be goofy, did you not catch I said your example was correct? I think you missed that in your lust for being right.

            – “your response again cuz”

            “Cuz” is not a word.
            I didn’t find this one, but it is slang moron. You are really going to call me on slang? I doubt you speak proper English 24hrs a day either. Once again your desperation to get me shows.

            “I agree that “the mars” doesn’t sound too correct,”

            Mars should be capitalized. I was not asking you to agree about how it sounds; I was pointing out that it is absolutely wrong in English, just as “The Jason” would be absolutely wrong. Got it

            Lol. I dont’t give a damn what you were asking for. Your entire point was that you can’t say ” the Mars” because it is not correct grammar and by the same token so is “the Earth.” That was your whole point which turned out to be dead wrong in the case of the Earth. Are you sure you got this point? Good.

            There was a typo too. You called me on that as well. It looks as if you don’t have a leg to stand on.

            Even when you attempt to grand stand you fail. Wow. You are so much fun it should be illegal.

          • Sal Volatile

            Did the missus write this one for you, too? It is fairly obvious by now the Jason has no idea how to write because the Jason lacks understanding of the fundamental concepts of written English and the associated rules thereof. May god have mercy on your soul.

          • jason T.

            It would seem your basic English skills are somewhat lacking there sal. Thanks for proving me right brother. Pleasure doing business with you “mr. Gump.”

          • jason T.

            Sad thing here that you didnt allow for any exceptions to the rule you thought you were employing. English has tons of exceptions to it’s rules. I agree that “the mars” doesn’t sound too correct, but that fact doesn’t negate it working for the earth.
            best case seario, the rules allow it as i have outlined in my other statement. Worst case, it’s an exception allowed for by those same rules. In any event….it is not wrong at all. You were wromg.

          • Khalim

            You have not considered “The Bronx” which is always correct. LOL

          • effinayright

            Except when you give someone “A Bronx Cheer”.

          • jason T.

            Sal,
            Tou were wrong in this case “The” is an article used to mark proper nouns so the Earth is correct.
            You have done nothing but mudsling to cover your mistake I am sorry you were wrong, but you can’t escape it. Be a man.

          • effinayright

            Not so long ago, Brits and Americans referred to the country south of Egypt as “The Sudan”.

            Many Brits still say “The Yemen”, “The Lebanon” and “The Levant”.

            Why? Because they just DO. English is funny that way.

            No one is confused when people speak of or write about “The Earth” or “Earth” when the context is clear.

            Remember that movie “The Earth Girls are Easy”?

            Or maybe that old Carol King song, “I Feel Earth Move Under My Feet”?

            Me neither.

        • jason T.

          Hey jason,
          We got it solved. It is proper English. I even verified through google.

        • Sal Volatile

          Let us say you had a friend from Mars. He doesn’t know a lot of English but he is learning and you are helping him. He comes over and you are showing him a map of the solar system and you point out his planet and say, “Mars.” Then you point to Earth and say what: “The Earth” or simply “Earth?”

          Remember, he does not know a lot of English and has no idea how a word like “the” can function in English. If you tell him “The Earth,” he might easily come to believe that the word “the” is really a part of the name, and henceforth and forever mistakenly refer to Earth as “The Earth.”

          Now, our little Martian friend goes back to Mars, with his solar system map and shows all his friends. When he points to their own planet, they all know it to be “Mars,” and when he points to Earth, they all say “The Earth,” just like you taught him.

      • Sal Volatile

        Your wife is the authority we should all defer to? Again, I ask: would you say “the Mars?” “The Jupiter?” “The Jason?” Earth, as used in the article, is a proper noun, and therefore, should be capitalized and referred to as simply “Earth.” This is remedial English here.

    • http://www.bowtoyoursensei.com/ Bow To Your Sensei

      You are the Idiot.

    • Jason Long

      What you mean is you can’t capitalize “Earth” when saying “the Earth”. You would have to say “the earth” for it to be correct. However, one can still say “the earth” to refer to our planet.

      Interesting how the capitalization of the word “earth” can change its meaning entirely.

      • http://blog.businessownerstoolbox.com/ Mike Van Horn

        In the future, when our descendants are hopping between star systems, visiting worlds with other intelligent races, communicating with them, we will discover that when we translate their words for their planet and star, the best translation will be “Earth” and “Sun.” All beings name their world something that corresponds to the term “Earth.”

        • Diego Hernandez

          We generally refer to our state of communal identity as that of being a nation; some view humanity as a collectivity of species, but we will most definitely identify ourselves as Humans and our “home world” as the Earth. “Their” home world’s will have proper names such as another state of communal identity; Iran, Russia,China.

          We may yet become a singularity… What?

          • http://blog.businessownerstoolbox.com/ Mike Van Horn

            Diego
            In all the languages I am familiar with, the name of our home planet means “world” or “the ground.” Occasionally, a people will give their nation that name, but “world” comes first. (Doesn’t “China” derive from the Han term for “middle earth”?)
            I’m assuming this same convention will extend to other intelligent races on distant worlds. They will name their own planet “world” in their tongue (or whatever they use for speech).

            I can make wild assertions like this; I’m a science fiction writer.

          • dmreed

            I seem to remember that China is named after the first Chin Dynasty emperor.

    • eyko

      Curiously, in my language (spanish) you can say “the earth” (la Tierra), or “planet Earth” (planeta tierra), but you can’t just say “Earth” when referring to the planet since the word “earth” is firstly a regular noun (that happens to also be our planet’s name) and there are rules to how you use the word. For example, you can say “This planet is called earth” but you can’t say “This is earth” since there is ambiguity in what you’re trying to say – is it just soil you’re talking about, or the name of the planet?

      Before reading your comment, I would’ve expected similar rules to exist in the English language. I’m sure there are rules to how the name “Earth” is used (even if they’re just exceptions to avoid confusion?)

      • http://deeper-thought.net/ Carl @ Deeper Thought

        That’s interesting. The only rule I know of in English is to capitalise Earth for the planet and earth for the dirt beneath your feet :)

      • daniel

        diablos sabes mas ingles que los ingleses … vives en latinoamerica o españa ?

      • ICanThinkAndDoThink

        Yes
        The English language has rules. The rules are far less logical or rational or even consistent than one would expect. & the young folks in the USA do not know these rules very well & ignore the ones they know.

    • Myothernamesagoodone

      There is an argument for saying that calling it Earth in the first place was extraordinarily dumb but as with all language there really is no right or wrong way to say it now. ‘The Earth, the planet Earth, Earth; all are justifiable and it would be the height of First World Problems (literally!) to be exercised over distinctions!

      • GuestWhom

        Correct…all are acceptable. Many grammar Nazis don’t realize that there are many exceptions to the rule and not everything they were taught in school was factually correct. There are many English grammar myths we were all taught, for example, the myth that a sentence should never end with a preposition. Arguing about whether or not saying “the” Earth or “the” Titanic is grammatically correct is ridiculous and definitely a 1st world problem.

        • Sal Volatile

          Let us say you had a friend from Mars. He doesn’t know a lot of English but he is learning and you are helping him. He comes over and you are showing him a map of the solar system and you point out his planet and say, “Mars.” Then you point to Earth and say what: “The Earth” or simply “Earth?”

          Remember, he does not know a lot of English and has no idea how a word like “the” can function in English. If you tell him “The Earth,” he might easily come to believe that the word “the” is really a part of the name, and henceforth and forever mistakenly refer to Earth as “The Earth.”

          Now, our little Martian friend goes back to Mars, with his solar system map and shows all his friends. When he points to their own planet, they all know it to be “Mars,” and when he points to Earth, they all say “The Earth,” just like you taught him.

        • ICanThinkAndDoThink

          Agreeing with you

          Also scratching my head trying to see if the grammer & word nazis have a single legitimate point in all this garbled text.

          Also in England they say ‘going to hospital’ or that some one is ‘in hospital’ . In the USA, we would say ‘the hospital’ meaning an unspecified one which is not very logical or ‘a hospital’ which is less commonly used but more logical or Proper Name Hospital.

          Some one (actually a group of some ones) has redefined planet. So I am not going to waste time arguing which conventional phrasing or word is more correct or more approved or more logical. If it has a path that fits what is the definition of a moon then it is a moon even if it is small, smaller than my cat or larger than our moon.

          Lots of folks here never played much with the Spyrograph toys that had different gear-based drawing tools. An orbit is not always round & the flattened view of our solar system is not how it really is. & the commenter on the BaryPoint is helpful. Possibly some who read my comment will want to reread that .

    • GuestWhom

      Look at Merriam-Webster and other sources for definitons of “earth” and examples of it in a sentence. Both are acceptable, with or without “the” in front of it but often “the Earth” just sounds better in certain examples because Earth is a named object/place and the use of “the” before the name of objects especially and sometimes places is common. Just like when you say the Titanic sank…it sounds funny if you instead said Titanic sank.

  • http://facebook.com/WeeRedBird WeeRedBird

    I thought, to be a moon, you have to orbit a planet. Cruithne orbits the sun.

    • http://facebook.com/WeeRedBird WeeRedBird

      Or should I put in the Starwars line of “That’s no moon”

    • http://deeper-thought.net/ Carl @ Deeper Thought

      I thought that! Hmmm. More like an asteroid with a more circular orbit if you ask me!

    • https://twitter.com/WayneDorniels Wayne Dorniels

      Well, technically everything in the solar system orbits the Sun.

      • http://facebook.com/WeeRedBird WeeRedBird

        Yes, technically everything orbits the sun, although convention usually words it as the moon orbits the Earth and the Earth orbits the sun.
        Its like saying you are being chased by a flea because it happens to be on the back of the dog running after you.

        But this rock does not orbit the Earth in any way.

        • Myothernamesagoodone

          Convention indeed. And as with most conventions far from accurate as a result. There is an entirely reasonable argument that in fact the moon is orbited by Earth for starters. And as the article states there is no reason to assume that an orbit requires a complete circuit of an object and particularly not one that starts and ends at the same point relative to that object. Those moons which behave like our own are in fact relatively rare and only hubris would equate the term ‘moon’ with only those objects which resemble it.

          • Jeff

            Most conventions are far from accurate? Really? You mean like sweeping generalisations are always suspect?

          • Myothernamesagoodone

            I may not have chosen the right word in ‘accurate’. What I mean is that conventions tend to the kind of standardisation that is unable to truly take account of all the niggling little things that might or might not qualify. The classic example, as discussed by Stephen Gould, is the word ‘fish’. Gould argues that whilst we all know what a fish is (by convention) there is no such thing as a fish biologically speaking because each of the species that is conventionally referred to as a fish is as different in fact from every other species that comes under that banner as to make it absurd to even consider the notion meaningful.

          • Dan

            It’s like the distinction between planet and dwarf planet. There may be a commonly accepted definition for moon, but as our knowledge of space expands we find all sort of exceptions. Perhaps the IAU has a definition.

        • Seijinvet

          The dog has intention to run after you, the flea does not.

          • http://facebook.com/WeeRedBird WeeRedBird

            Our moon’s main intention is to orbit the Earth. It orbits the sun because the earth does. Like the flea, it is along for the ride.

            Cruithne is more like another chasing dog, rather than another flea on our dog. A smaller dog that gets buffeted around by our bigger dog but is still chasing rather than riding.

          • Seijinvet

            Interesting concept, the moon having “intention”. Theologically the intention FOR the moon was to act as a timing device. It certainly has functioned that way. I find your perspective refreshing and a bit unique. Understand however that while it is not invalid it is no more valid than the converse idea.

          • http://facebook.com/WeeRedBird WeeRedBird

            Getting picky on the words being used rather than the concepts involved?

          • Seijinvet

            No, I really think it is interesting. Wrote a paper recently on consciousness as the ground of material reality.

    • disqus_atlq8Zmtsd

      It sounds like Cruithne does not have enough energy to escape Earth’s gravitational well (until it gets a boost from another body). So while it orbits the sun in tandem with Earth, it would very definitely be within Earth’s sphere of influence.

      • 1twothree4

        Even when it is on the OTHER SIDE of the sun from earth?

    • dogphlap dogphlap

      I watched the animation and it appeared to me to have made one orbit around Earth from the start of the animation to its end. A long way from a circle or an ellipse I’ll grant you and if Pluto doesn’t make it as a planet any more I can’t help thinking this should not make it as an Earth moon but my thoughts don’t count.

      • http://facebook.com/WeeRedBird WeeRedBird

        Aww, my comment, with animation, seems to have gone.
        It only looks like it is going round the earth as the earth is stationary in the image. There are images out there showing the orbit is an elliptical one around the earth. Holding the earth stationary, gives it a kidney bean shaped movement, relative to us, but we aren’t really stationary.

    • Seijinvet

      The Moon still orbits the Sun while orbiting the Earth. It could not stay in its relationship with Earth and not orbit the Sun as Earth orbits the Sun…

      • http://facebook.com/WeeRedBird WeeRedBird

        I’m not denying that the moon orbits the sun as a by-product of orbiting the earth which orbits the sun.
        Someone else made the same point, in this discussion, to which I made analogy about being chased by a flea because it is on the dog that is chasing you.

    • syx

      I agree with you. This object interacts with the Earth, but is not a satellite of the Earth. So it wouldn’t be a “second moon” as the article states. Also, there’s no evidence in this article that such a thing exist. It’s just words, and a poorly done, inaccurate computer generated illustration of Earth’s orbit around the sun. Not saying there’s not an object out there. Just that they haven’t provided any evidence. Just links to more words.

    • GuestWhom

      3753 Cruithne is an asteroid that is only 3 miles in diameter (while the actual moon of Earth is 2,159 miles in diameter) and yes, 3753 Cruithne does not revolve around the Earth so calling it a “moon” of Earth is a misnomer and is misleading. The closest it ever gets is 30 times the distance of the Moon from Earth so it is basically a speck in the solar system. The asteroid belt contains asteroids that are up to 590 miles in diameter so in the grand scheme of things this little asteroid has little significance.

    • 程肯

      Where did you get that?

      “Cruithne orbits the sun about once a year, but it takes nearly 800 years to complete this messy ring shape around the Earth’s orbit.”

      Since the Earth orbits the Sun in a year, then it stands to reason that Cruithne orbits the Sun in about a year, just like our Moon orbits the Sun in about a year.

  • http://deeper-thought.net/ Carl @ Deeper Thought

    This is fascinating. What I don’t understand is why we don’t send a probe to it to check it out since it’s so near on space scales. There’s probably loads more out there that can be classed as moons that we don’t know about yet. Shame they are so small. Most comets are probably bigger!

    • Myothernamesagoodone

      That it is so near and relatively undistinguished from other objects apart from its eccentric transit is precisely why there’s no great enthusiasm for the expenditure.

      • Diego Hernandez

        Money?

        I capitalized “money”. I believe that we will not learn from past mistakes here on earth and the capitalist pursuit will put us on this object. I want to control a builder bot on the the near object and beam energy at the earth.

        Minecraft on the object…

      • http://deeper-thought.net/ Carl @ Deeper Thought

        That’s the mystery though! Why is it not like the others! We need to see 😀

  • https://twitter.com/WayneDorniels Wayne Dorniels

    Very interesting, but when are we going to probe Uranus?

    • Myothernamesagoodone

      Aliens have been doing it for years, apparently!

      • https://twitter.com/WayneDorniels Wayne Dorniels

        To the delight of many, I’m sure.

  • Reginald Dean

    None the less it is a very beautiful orbit,I wish I could dance that well.

  • 1twothree4

    Cruithne does not orbit Earth and at times it is on the other side of the Sun, therefore it is NOT a moon of earth. What a load of populist crap.

    • turtle mann

      To be honest just cause are moon and all the other moons orbit in a circle around doesn’t mean there all the same way if you want to know really bad why don’t you contact NASA or something

      • turtle mann

        Although I see why you would think it doesn’t

        • 1twothree4

          Cruithne is in orbit around the SUN. Because it has a 1:1 orbital resonance with earth it just appears that sometimes it orbits the earth. It does not. I know this is way over your head. Look it up.

      • 1twothree4

        I don’t need to. I can do orbital mechanics. I also know when to use ‘our moon’ instead of ‘are moon’. LOL

  • VyperX

    “There’s a good chance that that will put paid to our erstwhile spare moon, flinging it out of harm’s way, and out of the Terran family.”

    Anybody care to translate that into English? Thank you.

    • larrytom2

      That means that Venus’ gravitational pull will alter the spare moon’s orbit such that it will break from the gravitational “control” of Earth and no longer be a “moon” for us.

  • Ed Lerner

    “If Cruithne struck the Earth, though, that would be an extinction-level event (…)”

    Someone call Bruce Willis

  • Bronxboy

    Cruithne sounds like a name invented by HP Lovecraft.

  • jason T.

    To all,
    I’m glad we resolved that Sal was inncorrect in his assertion “the Earth” was not properly used in this story. I provided confirmation of this through google. Thanks for your time.

  • Sal Volatile

    Let us say you had a friend from Mars. He doesn’t know a lot of English but he is learning and you are helping him. He comes over and you are showing him a map of the solar system and you point out his planet and say, “Mars.” Then you point to Earth and say what: “The Earth” or simply “Earth?”

    Remember, he does not know a lot of English and has no idea how a word like “the” can function in English. If you tell him “The Earth,” he might easily come to believe that the word “the” is really a part of the name, and henceforth and forever mistakenly refer to Earth as “The Earth.”

    Now, our little Martian friend goes back to Mars, with his solar system map and shows all his friends. When he points to their home planet, they all know it to be “Mars,” and when he points to Earth, they all say “The Earth,” just like you taught him.

    • ICanThinkAndDoThink

      And all his Martian friends are better at English than the younger twitter I passed school by passing multiple choice darken the correct circle tests.

      You make a very good point.

  • John Masters

    Sigh. All you two-dimensional thinkers are applying Euclidean rules to three dimensional bodies. Yes, its a tiny rock. Yes, it trails the Earth’s gravity more than truly orbits. Yes, its probably a trivial distinction. But, if it orbits the Earth once in 800 years that qualifies it as a satellite of Earth, and lacking a better definition, it is correctly designated as a “moon”. Maybe we should just accept some diminutive version. How about “moonlet”?

  • jason T.

    To all,
    I’m glad we resolved that Sal was inncorrect in his assertion “the Earth” was not properly used in this story. I provided confirmation of this through google. Thanks for your time

  • jason T.

    Sal. I see my final post did not make into the conversation so I will re-post it now.
    II am sorry you can’t grasp this simple concept. Truly, it would be nice if you were able to learn from your mistakes. I outlined ,l outlined CLEARLY that “The” is a definite article used to mark a proper noun. The definition never said it was applicable every where. Neither did I. I explained this to you, offered my wife’s opinion as she working in publishing, etc. You ignored it. You somehow came up with a “real” expert to back you up. I found him and saw that he too used “the Earth” in one of his books. this shut down your only attempt at verifiable proof.
    Your sole argument was ” can you say the Mars or the Jason?” This very comparison underlies the assertion that since you can’t say the Mars, you can’t say The Earth either. You denied this but it is true. You logic was flawed and to date, this is the only real argument you have made. Numerous times I asked for verifiable proof and you were unable to respond as instructed.

    I think you are the one who doesn’t understand the subject and refuses to acknowledge it. Further, you can’t even come up with a rule of grammar that negates my point. all you can do is make horrible analogies that don’t make a solid point.
    Better luck in the future man

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