Martin Rees: We need to cherish our 'pale blue dot' in the cosmos

From a speech by the Astronomer Royal to the Foundation for Science and Technology's Christmas reception

Share
Related Topics

For about 40 years, we've been familiar with the view of Earth from Space. Suppose some aliens had been watching our planet for its entire history, what would they have seen? Over nearly 4.5 billion years, Earth's appearance would have altered very gradually. The continental land masses drifted; the ice cover waxed and waned; successive species emerged, evolved and became extinct.

Yet in just a tiny sliver of the Earth's history - the most recent one millionth part, just a few thousand years - the aliens would have seen that the patterns of vegetation altered much faster than before. The start of agriculture would have set that in train. Then would have come the imprint on the terrain of humans, powered by tools.

But then there were quite different and even more abrupt transformations. Within 50 years, or little more than one hundredth of a millionth of the Earth's age, the carbon dioxide in the atmosphere began to rise anomalously fast. The planet became an intense emitter of radio waves. At about the same time metallic objects left the planet's surface and escaped the biosphere completely. Some were propelled into orbits around the Earth; some journeyed to the Moon and planets.

The aliens could predict that the biosphere would face doom in 6 billion years, when the predictions show the Sun will die. But could they have predicted this unprecedented spike less than halfway through the Earth's life, signalling alterations induced by human beings occupying less than a millionth of the elapsed lifetime of the Earth?

What might the [aliens] witness in the next 100 years? Will there be a final spasm followed by silence? Or will the planet stabilise? This enlarged perspective gives an extra motive to cherish our "pale blue dot" in the cosmos.

React Now

Latest stories from i100
Have you tried new the Independent Digital Edition apps?
iJobs Job Widget
iJobs General

Marketing Manager - Leicestershire - £35,000

£30000 - £35000 per annum: Ashdown Group: Marketing Manager (CIM, B2B, MS Offi...

Marketing Executive (B2B and B2C) - Rugby, Warwickshire

£22000 - £25000 per annum: Ashdown Group: A highly successful organisation wit...

SEN Coordinator + Teacher (SENCO)

£1 per day: Randstad Education Leeds: Job Purpose To work closely with the he...

Research Manager - Quantitative/Qualitative

£32000 - £42000 Per Annum: Clearwater People Solutions Ltd: Our client is curr...

Day In a Page

Read Next
Piper Ryan Randall leads a pro-Scottish independence rally in the suburbs of Edinburgh  

i Editor's Letter: Britain survives, but change is afoot

Oliver Duff Oliver Duff
Some believe that David Cameron is to blame for allowing Alex Salmond a referendum  

Scottish referendum: So how about the English now being given a chance to split from England?

Mark Steel
Scottish referendum: The Yes vote was the love that dared speak its name, but it was not to be

Despite the result, this is the end of the status quo

Boyd Tonkin on the fall-out from the Scottish referendum
Manolo Blahnik: The high priest of heels talks flats, Englishness, and why he loves Mary Beard

Manolo Blahnik: Flats, Englishness, and Mary Beard

The shoe designer who has been dubbed 'the patron saint of the stiletto'
The Beatles biographer reveals exclusive original manuscripts of some of the best pop songs ever written

Scrambled eggs and LSD

Behind The Beatles' lyrics - thanks to Hunter Davis's original manuscript copies
'Normcore' fashion: Blending in is the new standing out in latest catwalk non-trend

'Normcore': Blending in is the new standing out

Just when fashion was in grave danger of running out of trends, it only went and invented the non-trend. Rebecca Gonsalves investigates
Dance’s new leading ladies fight back: How female vocalists are now writing their own hits

New leading ladies of dance fight back

How female vocalists are now writing their own hits
Mystery of the Ground Zero wedding photo

A shot in the dark

Mystery of the wedding photo from Ground Zero
His life, the universe and everything

His life, the universe and everything

New biography sheds light on comic genius of Douglas Adams
Save us from small screen superheroes

Save us from small screen superheroes

Shows like Agents of S.H.I.E.L.D are little more than marketing tools
Reach for the skies

Reach for the skies

From pools to football pitches, rooftop living is looking up
These are the 12 best hotel spas in the UK

12 best hotel spas in the UK

Some hotels go all out on facilities; others stand out for the sheer quality of treatments
These Iranian-controlled Shia militias used to specialise in killing American soldiers. Now they are fighting Isis, backed up by US airstrikes

Widespread fear of Isis is producing strange bedfellows

Iranian-controlled Shia militias that used to kill American soldiers are now fighting Isis, helped by US airstrikes
Topshop goes part Athena poster, part last spring Prada

Topshop goes part Athena poster, part last spring Prada

Shoppers don't come to Topshop for the unique
How to make a Lego masterpiece

How to make a Lego masterpiece

Toy breaks out of the nursery and heads for the gallery
Meet the ‘Endies’ – city dwellers who are too poor to have fun

Meet the ‘Endies’ – city dwellers who are too poor to have fun

Urbanites are cursed with an acronym pointing to Employed but No Disposable Income or Savings
Paisley’s decision to make peace with IRA enemies might remind the Arabs of Sadat

Ian Paisley’s decision to make peace with his IRA enemies

His Save Ulster from Sodomy campaign would surely have been supported by many a Sunni imam