Sand or planets

[thefinders]

Are there more grains of sand or more planets?

[tiggerblue10]

Would you like to do a head count of both and let us know what your findings are ;-)

[vehelpfulguy]

Well we know there are a eight planets in our solar system (Earth, Mars, Venus, Jupiter etc) but even on the very edge of OUR solar system we cannot see if there are any more.

In fact Pluto (which is a LONG way away), which has been designated a planet for many years, probably IS NOT a planet but just a lump of floating rock.

So as we cannot even see all the planets in OUR solar system we have no idea how many planets there are in ALL the solar systems.

Maybe you means Stars, of which our Sun is one.

Well again, we dont really have any idea how many Stars there are in all the Solar Systems.

Our solar system is in the Milky Way galaxy, and one estimate of the number of stars in the Milky Way is 400 BILLION.

And it is estimated there are BILLIONS of galaxies, each of which contain BILLIONS of stars.

And of course EACH of those stars probably have planets going round them (but as we cannot even see all the stars we have no chance of seeing their planets, which give off no light).

Mind boggling eh !! ...and a but frightening.

[joggerjayne]

That sounds quite a lot :-)

[wildwood]

There are 7,500,000,000,000,000,000, or seven quintillion five quadrillion grains of sand on the world's beaches, give or take two.

It is however impossible to even guess how many planets there are as light from zillions of stars/constellations has not reached us as yet and most of them are spreading the other way from us so the combined separation speed of the Milky way and the others exceeds the speed of light so that light will never reach us.

[Avatar]

Or, why isnt this question in the science area?

[wildwood]

Avatar, this question is 100% related to Nature.