IS THERE AN EARTH-II

[JOT]

This is probably a stupid question but: "Has anyone ever looked on the other side of the sun to see if there is another planet (EARTH-II) in the same orbit as the Earth but 180 degrees opposite us?" I know this sounds like a scene from a Star Trek movie but I promise I came up with the question before I remembered the movie scene. In fact I was telling a co-worker where little green women came from - making up tall tales as I explained. After I finished, I realized I was not sure that anyone had ever looked. Please put my mind a ease by telling me - Earth-II will not be over here when we are over there.
Thanks in advance,
JOT

 

[DrRocket]

This is probably a stupid question but: "Has anyone ever looked on the other side of the sun to see if there is another planet (EARTH-II) in the same orbit as the Earth but 180 degrees opposite us?" I know this sounds like a scene from a Star Trek movie but I promise I came up with the question before I remembered the movie scene. In fact I was telling a co-worker where little green women came from - making up tall tales as I explained. After I finished, I realized I was not sure that anyone had ever looked. Please put my mind a ease by telling me - Earth-II will not be over here when we are over there.
Thanks in advance,
JOT

If there were such a planet the effect would be seen in the perturbation of the orbits of the other planets and of space craft sent into deep space.

No, actually it is really there, it travels just a little faster than our Earth, and the collision with Earth II is the disaster predicted by the Mayas for 2012. We are DOOMED.

 

[bearack]

This is probably a stupid question but: "Has anyone ever looked on the other side of the sun to see if there is another planet (EARTH-II) in the same orbit as the Earth but 180 degrees opposite us?" I know this sounds like a scene from a Star Trek movie but I promise I came up with the question before I remembered the movie scene. In fact I was telling a co-worker where little green women came from - making up tall tales as I explained. After I finished, I realized I was not sure that anyone had ever looked. Please put my mind a ease by telling me - Earth-II will not be over here when we are over there.
Thanks in advance,
JOT

If there were such a planet the effect would be seen in the perturbation of the orbits of the other planets and of space craft sent into deep space.

No, actually it is really there, it travels just a little faster than our Earth, and the collision with Earth II is the disaster predicted by the Mayas for 2012. We are DOOMED.

ROFLMAO!!!!!!!!

 

[ZenGalacticore]

Nope. No Earth II 180 degs opposite us, but there was a fairly good sci-fi flick that dealt with the fantasy that came out in the late 60s early 70s called "Journey to the Far Side of the Sun". The astronaut lands on a parallel but mirror/reverse Earth. Everyone thinks the mission failed-as does the astronaut- until he realizes that everything is spelled backwards. Of course, the people on the mirror Earth didn't speak backwards, so it was kind of dumb. But I enjoyed it as a kid.

 

[MeteorWayne]

Seriously, though, that area has been well observed by a number of spacecraft.

 

[xXTheOneRavenXx]

LMAO!!! Wait, I'm from there :mrgreen:

 

[3488]

Seriously, though, that area has been well observed by a number of spacecraft.

That is very true Wayne.

There is no second Earth lurking in our orbit over the other side of the Sun.

Pertubations with Mercury & Venus, as well as to asteroids & comets in that area would also have been detected.

Also during some total solar eclipses, a potential second Earth would probably have been spotted, as the Earth's orbit is not a perfect circle & from October to April, the Earth is travelling slightly faster than between April & October (perihelion is in January, aphelion in July), so the counter Earth would by default be travelling slightly more slowly, thus would appear to one or the other side of the Sun during these times.

Andrew Brown.

 

[MeteorWayne]

Good one Andrew!

 

[Smersh]

... I know this sounds like a scene from a Star Trek movie ...

Actually, I thought maybe you'd seen the 1969 movie "Doppleganger." http://www.imdb.com/title/tt0064519/

Welcome to Space.com!

 

[3488]

Good one Andrew!

Thanks Wayne.

Also me being a bit slow, a counter Earth would have been observed by LASCO on SOHO, rocking back & forth from behind the Sun.

Of courrs only in early April & early October when the Earth & the potential counter Earth are 1 AU from the Sun, would they truly be in line. At other times, either Earth would be running slightly 'fast', counter Earth slightly 'slow' & vice versa the alignment would be broken & the counter Earth in theory would be observable, though it would always appear very close to the Sun.

However it would certainly be visible in total solar eclipses not in April & October & certainly would have been found by solar observing spacecraft like SOHO, Solar Max, Skylab, Yohkoh, STEREO, etc.

Andrew Brown.

 

[3488]

... I know this sounds like a scene from a Star Trek movie ...

Actually, I thought maybe you'd seen the 1969 movie "Doppleganger." http://www.imdb.com/title/tt0064519/

Welcome to Space.com!

Cheers Smersh,

I'll have to check "Doppleganger" out.

Andrew Brown.

 

[Smersh]

Cheers Smersh,

I'll have to check "Doppleganger" out.

Andrew Brown.

I wouldn't be in too much of a hurry Andrew. The movie was absolute crap IIRC!

 

[ZenGalacticore]

Well gee guys, I hope you're not referring to what Zen posted. I did say it was a 'fantasy'. It's a silly idea, ok? I just mentioned a sci-fi movie- 'Journey to the Far Side of the Sun'- that dealt with the fantasy.
Even if all the planets were in perfectly circular orbits, we'd know there was no Earth II, or Mars or Venus II, for that matter. It wouldn't take a scientific genius to deduce the facts.

 

[Smersh]

Well gee guys, I hope you're not referring to what Zen posted. I did say it was a 'fantasy'. It's a silly idea, ok? I just mentioned a sci-fi movie- 'Journey to the Far Side of the Sun'- that dealt with the fantasy.
Even if all the planets were in perfectly circular orbits, we'd know there was no Earth II, or Mars or Venus II, for that matter. It wouldn't take a scientific genius to deduce the facts.

Hi Zen, I just realised we are talking about the same movie. According to the IMBD link I gave, it looks like it was called "Doppleganger" in Europe and "Journey to the Far Side of the Sun" in the US.

What really made the movie a bit silly in my opinion though, was as you pointed out . Everything on "Earth 2" was a mirror image of everything happening on Earth 1. At the very same moment a team of astronauts set out from Earth 1 to visit Earth 2, their "dopplegangers" were doing the same and setting out to visit Earth 1. (You watched it as a kid though and enjoyed it - if I had watched it as a kid I probably would have liked it as well!) And I do realise you are talking about a pure fantasy.

As for the concept itself though of a twin Earth with the same orbit, but exactly opposite us and always out of view because it's the other side of the Sun, I suppose it's a possibilty in some other solar systems (although I guess it would take quite a coincidence - the orbital speed would have to be completely identical for a start!)

Of course though as Andrew correctly pointed out, we know there is no such planet in our own system because SOHO and other spacecraft would have spotted it long ago.

 

[MeteorWayne]

One small point. Unless we could spot it from earth, SOHO wouldn't see it either. Since SOHO resides at the earth's L1 point, it is always between we and the sun, so such a hypothetical planet would always be behind the sun. Any spacecraft in any other solar orbit would be able to catch it though.

 

[JOT]

Thanks guys for all the great info. I've been able to sleep well knowing there's nothing as big as the Earth lurking behind the Sun. I guess I'll have to revise my story about little green women. Maybe it's a huge space craft (Death Star) on the other side of the Sun. How does that sound or maybe I'll have little green women made of green dark matter. That way they can just appear out of the blue (oppps, I meant green).
Seriously, I have a question about Dark Matter (regardless of the color). Let's see if I have this close (short version) - - - - - Very, Very smart people have determined the Universe is expanding instead of shrinking. More smart people (who are good with math) added up all the stuff in the Universe and plugged this number into their expanding/shrinking formula. When they got the answer, they discovered that the Universe is missing some stuff, assuming the Universe is expanding, assuming they added stuff correctly, assuming their formula is correct.

Since there was a lot of missing stuff, I assume all the people smart enough to check their math, went crazy trying to catch the other smart people in a math mistake because there could not be that much stuff missing. When they could not find a mistake, they invented Dark Matter.

Question #1 - Is my short version more or less accurate?
Question #2 - Since so little is known about the physics of black holes, how could they possibly know how much matter (dark or otherwise) has been eaten by the unknown number of black holes?
Question #3 - I read somewhere that the mass of photons in the Universe was taken into account when they were doing the math. If true, how much mass does a photon have? And, how did they determine how many photons are in the Universe? If you just figure whole degrees, I calculate every cubic inch, foot, mile, and light year of space has photons passing through from 129,240 different directions.
Question #4 - If Earth-II is made of Dark Matter - - - Sorry!! (there is no Earth-II, there is no Earth-II, there is no Earth-II)

Thanks in advance,
JOT

 

[Mee_n_Mac]

Question #1 - Is my short version more or less accurate?

Nope. Sounds like you've got dark matter and dark energy confused. Dark matter was conjured up as an explanation for why some galaxies aren't acting in accordance with known laws of gravity. If you think of galaxies as nothing more than a bunch of stars (you can toss some black holes in and put a big one at the center if you wish) then if you have a spiral galaxy which rotates about it's center you should be able to predict (from gravity) how fast each star is going in it's orbit around the center. Well a number of such galaxies were looked at and it was discovered that the velocites measured don't agree with the predictions. Oh oh, is our understanding gravity wrong. Perhaps but so far the theory we have has proven to be correct in every other instance. What else might account for such a difference ? Well if you put a lot of "stuff" in the right places in and about a galaxy you can predict the velocities measured. Problem is we can't see this "stuff". It doesn't give off light, it's dark matter. We don't know what this stuff is but we do see the effect.

Dark energy was conjurered up as a result of looking at distant supernovae. Certain types are thought to well enough understood that when the nova happens we know just how much energy they give off over a period of time. Thus we can predict how "bright" they should be and from that get a good estimate of how far away they are. So 2 independant teams were looking at these things in an attempt to determine the fate of the Universe. It was thought at the time that the collective mass of the Universe was probably large enough to have enough gravity to slow down the expansion of the Universe, perhaps coming to a complete halt and then reversing itself. But to their amazment what they found was that the Universe's expansion wasn't slowing down, it was, presently, speeding up. It looked like the Universe's expansion was slowing but then it stopped slowing and started accelerating some ? 5 ? billion years ago. What is responsible for this ... we don't know but we call it dark energy.

Question #2 - Since so little is known about the physics of black holes, how could they possibly know how much matter (dark or otherwise) has been eaten by the unknown number of black holes?

I don't think we "know" as much as we have some estimate. You can measure the mass of a black hole by measuring the effect it's gravity has on things orbitting the BH. Dump 100 kg into a BH and it has 100kg more mass.

Question #3 - I read somewhere that the mass of photons in the Universe was taken into account when they were doing the math. If true, how much mass does a photon have? And, how did they determine how many photons are in the Universe? If you just figure whole degrees, I calculate every cubic inch, foot, mile, and light year of space has photons passing through from 129,240 different directions.

A photon has no rest mass. As for the rest of your question I defer to someone else.

 

[DrRocket]

Question #3 - I read somewhere that the mass of photons in the Universe was taken into account when they were doing the math. If true, how much mass does a photon have?
Thanks in advance,
JOT

E= mc^2 m=E/c^2 E=hf m=hf/c^2

 

[ZenGalacticore]

Well Smersh, even though it was probably a lame movie, I like the American title better. What in the hell, if I may ask, is a 'dopplehanger', or whatever?

BTW, who is that on your avatar? He looks familiar. Is that the love-child of Saddam Hussein and Arthur C. Clarke? :lol:

Zen himself has to settle with the generic 'SpaceGhost looking guy', as I am a techno-****** and don't know how to do that or even provide links!

 

[rogerinnh]

1) No there is no Earth 2 lurking on the other side of the Sun. Planets do not lurk. They do not have the capacity to lurk. They are unlurkable.

2) It seems to me that the only way a twin Earth could remain unviewable from Earth would be if both planets were in precisely the same orbit AND the co-oribit was precisely circular. In an elliptical orbit (which constitutes 9.9999999% of all orbits) the orbiting object moves faster when it's closest to the object that it is orbiting and moves slower when it's farthest away. Thus (I think) that means that the two planets would only be exactly in alignment with the orbited object, and therefore visibly blocked by the orbited object, when the one planet is at it's closest position and the other planet is at its farthest position. At all other positions in the orbit one planet would be "ahead"in its orbit and the other planet would be "behind"in its orbit, so each should be viewable from the other almost all the time.

3) Of all the known planets (other than Earth) none have a twin. If they did we would defintely be able to see it. What would prompt you to think that there is something so incredibly unique about Earth that it, and it alone, would have a twin (other than 1950s science fiction TV shows)?

4) It seems to me that any solar system with more than two orbiting planets would almost guaranee that no two of the planets could be "twins", since the existence of the other planets would cause mutual perturbations of the orbits, practically guaranteeing that no two of them would be co-orbital.

 

[dragon04]

There was an Earth II on TV back in the late '80's. Terrible show.



Does that count?