Professor Brian Cox has told the story of “worlds born and worlds lost” on Earth’s closest neighbours, Mars, Venus and Mercury, in a new BBC2 series, saying each “appears to have had a moment where it’s enjoyed almost Earth-like conditions.”’
According to the physicist, 3.5 billion years ago Mars had an atmosphere rich in greenhouse gases but could not hold on it due to a relatively small size. This allegedly made its rivers, following for millions of years evaporate into space, “leaving only traces, frozen in patches across the planet, where missions continue to search for the first signs of extraterrestrial life”. Cox, however, did not exclude that living creatures could be found there.
“If life does exist out there it’ll only be simple. Nothing as complex as you and me, or even a plant,” he noted.
Cox also suggested that Mercury, with daytime temperatures of up to 430 C and —170C at night, might have had another story.
He points out that the planet’s crust, formed after its birth, became enriched in volatile elements, which could only have happened millions of kilometres away from its current position near the Sun. According to him, a fatal strike might have changed its destiny billions of years ago, kicking it closer to the seething centre of our solar system.
“A place where if it had stayed, its destiny could have been very different”, the scientist concluded.
Venus might be called another “loser” because it could have also enjoyed Earth-like conditions. But the growth of the Sun might have evaporated any water from its surface.
“Venus is a vision of hell where no life can survive. Where did it all go wrong? Why did one world, Earth, become heaven and one become hell? Venus had reached a tipping point, a runaway greenhouse effect”, Cox contemplated in the documentary.
According to him, the Sun’s “relentless” aging process promises nothing good for life on Earth, as the centre of our system expands, turning into a Red Giant.
Before his academic career, Cox was a keyboard player for the band D:Ream.
After it disbanded in 1997, he was awarded a PhD in High Energy Particle Physics in Hamburg, and became a household name with his BBC series Wonders Of The Solar System.