How do we know there is not another planet like ours, on the far side of the Sun?

Answer 1

Empirically, space probes such as Voyager have photographed that region. Theoretically, due to the perturbations of the other planets, the earth's orbit actually wanders around a bit. Being in a different position relative to the other planets, the perturbations on it would be different, so it would wander around differently. Eventually (say after a few thousand years), it would wander into view.

In fact, since it would have essentially the same orbit, it would have wandered right in to the earth billions of years ago and formed a single larger planet. Earth was indeed formed by many such collisions of smaller bodies in a similar orbit, the last big collision involved early earth being hit by a mars sized planet. The debris kicked up into orbit re-condensed there and formed the moon.

Answer 2

The Idea has been used if a few Sci Fi stories , But a planet on the far side of the sun would be detected by the way it would interfere with the orbits of the other planets in our solar system

Answer 3

Uh... because we rotate around the sun and eventually end up on the other side of the sun every six months. (It takes 12 months to rotate around the sun, so six months from now we will be on the other side of the sun).

Maybe you mean on the other side of the galaxy?

Or the next closest star? (The sun is a star. All the stars you see in the sky at night are just like our sun, except for sometimes you can see Venus reflecting the sunlight in our own solar system in the night sky, resembling another star).

The next closest star is Proxima Centauri V645. It is 4.2 light years away...meaning if we could travel the speed of light, (which is about 186,000 miles per second) it would take us 4.2 years to reach the star. So, we dont know whats on the other side of it.

Proxima Centauri is not as bright as our sun, but its neighbor, Alpha Centauri, is just a bit brighter than our sun. So, once again, it could be possible that someone was on a planet behind that one, too. Alpha Centauri is 4.4 light years away.

Otherwise, we have extensively explored our own solar system and studied the planets within it. I think we would have found life like ours on other planets within our own solar system.

Now, outside of that...you never know.

Answer 4

The existence of the planets is calculated with the effects of gravitational pull upon the rest of the planets. Their orbits are predictable their gravitational pulls affecting one another.

If there were another planet on the other side of the sun it would change the paths of the planets as they made approaches to that one as they do to this one and we could see the effects.



g-day!

Answer 5

First off it would be a HUGE long shot since it would have to have exactly the same orbit as Earth, if it was even the slightest bit different, sometime in the last few hundred years it would have been visible. Second, it would have affected the orbit of Venus in a detectable way. Third, we have imaging satellites such as Soho which are not in the solar/planetary plane that would have seen it.

Answer 6

Since we rotate "around" the sun. There has been another
planet like ours found. The planet is just the right size, might
have liquid water form, and in "galactic" terms is retalively nearby at 120 trillion miles away. The star it orbits, known as
the "red dwarf" is smaller and cooler than our sun. *. / :-})

Answer 7

Because we can measure the sun's wobble and the orbits of other planets/celesial objects. They are not affected by the gravitational pull of another object.

Answer 8

There is, it was discovered only a month or two ago, well its the first discovery of a planet with water and similar atmosphere
I think it was 20thousand light years away

Answer 9

Because it would not remain behind the Sun. It would enter a horseshoe orbit with the Earth.

Answer 10

Because the orbits of the other planets would be disturbed and it would be realised that another unseen planet was causing this.