Could Mars ever have been earthlike, and...?

[flobadob]

Could Mars, say a few million/billion years ago have been like earth is now, before becoming what we see it as today, pretty lifeless and desolate? Furthermore, if that is a possibility, could earth end up the same way as Mars is now?

Also, there are some images I saw on this site http://www.presidiacr...-photographs-of-mars/ What is the story with the 3rd image? Are those black things rising out of the surface and what are they?

[12thPaladin]

I read a long time ago that a popular theory was Mars was once indeed similar to Earth with a thicker atmosphere (than present) and with surface water.
Due to it's size the core of churning molten iron set (for want of a better description) and Mars lost it's magnetosphere which like Earth deflects the solar wind, without this defence the atmosphere was stripped away adding to further cooling and intense radiation leaving the planet as we see it now.
As for Earth's future, we're more likely to end up similar to Venus with a runaway greenhouse effect.
I have nothing to corroborate this, as I said it's something I read years ago and most probably has been replaced with more up-to-date theories.

[Andyvon]

That was my understanding too Paladin. There's also the fact Mars possessed huge quantities of liquid water in it's first 2 billion years. There's plenty of evidence of oceans, rivers, lakes etc and much is now speculated to be stored underground in aquifers or permafrost. There's also much speculation how far life evolved in those oceans but there's no reason it didn't become more advanced than single-celled organisms. Many scientists now think bacterial life exists deep in the Martian crust, as it does on Earth.

[beso]

There is no doubt the Earth will be dry and desolate within less than a billion years.

As stars progress through their life they burn faster and become hotter. The Earth will heat up and lose all its water.

[jomifl]

The 'black things rising out of the surface' are shadow filled gullies on the side of valleys. you have to visualise where the lighting is coming from and then it all makes sense.

[mibn2cweus]

//What is the story with the 3rd image? Are those black things rising out of the surface and what are they?//
http://www.wired.com/...0/01/gallery-mars/12/

[jomifl]

Mib..I bow to your greater insight..

[mibn2cweus]

(jomifl, knowing me, I’d wager the shoe will be on the other foot before long . . . ;o)