Why the Earth's twin became a wasteland

It is a world stripped of water and scarred by searing temperatures hot enough to melt lead. Yet Venus may once have been a planet much like Earth, where vast oceans of water could have supported life.

The first detailed analysis of data gathered by a European space probe has revealed tantalising evidence that Venus often considered Earth's twin planet became so inhospitable for life because of a series of chance events.

Scientists have confirmed that the similarities between Venus and Earth were overshadowed by a shift in the former's history that led to the loss of the Venusian oceans, an atmosphere clogged with carbon dioxide and a runaway greenhouse effect that gave rise to severe global warming.

The Venus Express, launched two years ago and orbiting the planet for a year taking measurements, has helped to shed light on why the climate of Earth's twin is so severe, said Professor Fred Taylor, of Oxford University. "It is now becoming clear why the climate on Venus is so different from Earth, when the planets themselves are otherwise quite similar," he said.

Venus is the closest planet to Earth in terms of its distance from the Sun, its mass, radius, density and chemical composition. Venus differs in terms of its slow rate of rotation once every 243 Earth days and yet it is hard to imagine the two climates being more different.

"These differences are not just down to Venus being closer to the Sun," Professor Taylor said. "We now know that the lack of a protective magnetic field and the differing planetary rotation rates also play a role in ensuring many of the atmospheric processes we observe on Earth occur at a much faster rate on Venus.

"Our new data make it possible to construct a scenario in which Venus started out like the Earth, possibly including a habitable environment, billions of years ago, and evolved to the state we see now."

Venus Express has confirmed that the lack of a magnetic field made Venus vulnerable to the water-stripping properties of the solar wind, a high-speed stream of charged particles that split water molecules in two and allow the vital hydrogen in water to escape into space.

The oceans on Earth have been critical in trapping carbon dioxide as carbonate rocks; on Venus, the carbon dioxide has been released into its atmosphere to cause a runaway greenhouse effect, with surface temperatures averaging about 450C.

The latest results from Venus Express, in the journal Nature, show the atmosphere is a turbulent, three-dimensional structure which can be divided into four major components from the Venusian equator to the poles, Professor Taylor said. They also reveal that Venus experiences lightning strikes, and that they may even be more common than on Earth, which has important implications for the chemistry of the planet's atmosphere.

More than 30 spacecraft have visited Venus since the first probe, Mariner 2, was sent by the United States in 1962. Venus Express is loaded with scientific instruments designed to monitor a suite of phenomena, such as the amount of heavy water vapour in the atmosphere and the strength of any magnetic field. One of the biggest mysteries is how Venus lost its water, although the lack of a protective magnetic field suggests it was something to do with the solar wind.

Andrew Ingersoll, of the California Institute of Technology in Pasadena, said: "Because Venus is close to Earth in so many ways, it seems likely that the two planets started out similarly. Venus must once have had an ocean's worth of water, but lost it somehow. The escape mechanism probably involves the solar wind the stream of charged particles emanating from the Sun which strips atoms and ions out of the atmosphere. But the details are contradictory."

Venus by the numbers

457C surface temperature 96% of atmosphere made up of carbon dioxide, leading to surface pressure 92 times greater than that of Earth. The sun rises and sets every 117 earth days and the planet spins once relative to the stars every 243 days. As night falls, the temperature can drop by up to 240C. At cloud-level, wind speeds reach 360 kph three times hurricane force. At its poles, instead of cold cores, Venus has cold collars, inside of which air temperature rises by 263C.

News
people
Arts and Entertainment
Armstrong, left, and Bain's writing credits include Peep Show, Fresh Meat, and The Old Guys
TVThe pair have presented their view of 21st-century foibles in shows such as Peep Show and Fresh Meat
Arts and Entertainment
Keys to success: Andrew and Julian Lloyd Webber
arts + entsMrs Bach had too many kids to write the great man's music, says Julian Lloyd Webber
Sport
footballMan City manager would have loved to have signed Argentine
PROMOTED VIDEO
News
people
News
i100
Arts and Entertainment
Hand out press photograph/film still from the movie Mad Max Fury Road (Downloaded from the Warner Bro's media site/Jasin Boland/© 2014 Warner Bros. Entertainment Inc.)
films'You have to try everything and it’s all a process of elimination, but ultimately you find your path'
Arts and Entertainment
Imelda Staunton as Dolores Umbridge in the Harry Potter films
books

New essay by JK Rowling went live on Pottermore site this morning

News
people

Top Gear presenter is no stranger to foot-in-mouth controversy

News
Russia Today’s new UK channel began broadcasting yesterday. Discussions so far have included why Britons see Russia as ‘the bad guy’
news

New UK station Russia Today gives a very bizarre view of Britain

News
ebooksAn unforgettable anthology of contemporary reportage
Arts and Entertainment
Keira Knightley and Benedict Cumberbatch at the premiere of The Imitation Game at the BFI London Film Festival
filmsKeira Knightley tried to miss The Imitation Game premiere to watch Bake Off
News
i100
Sport
Enner Valencia
footballStriker has enjoyed a rapid rise to fame via winning the title with ‘The Blue Ballet’ in Ecuador
Arts and Entertainment
A top literary agent has compared online giant Amazon to Isis
arts + entsAndrew Wylie has pulled no punches in criticism of Amazon
Arts and Entertainment
Charlie Sheen said he would
tv

Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Mobile Developer (.NET / C# / Jason / Jquery / SOA)

£40000 - £65000 per annum + bonus + benefits + OT: Ampersand Consulting LLP: M...

Humanities Teacher - Greater Manchester

£22800 - £33600 per annum: Randstad Education Manchester Secondary: The JobAt ...

Design Technology Teacher

£22800 - £33600 per annum: Randstad Education Manchester Secondary: Calling al...

Foundation Teacher

£100 - £125 per day: Randstad Education Chelmsford: EYFS Teachers - East Essex...

Day In a Page

Bryan Adams' heartstopping images of wounded British soldiers to go on show at Somerset House

Bryan Adams' images of wounded soldiers

Taken over the course of four years, Adams' portraits are an astonishing document of the aftermath of war
The drugs revolution starts now as MPs agree its high time for change

The drugs revolution starts now as MPs agree its high time for change

Commons debate highlights growing cross-party consensus on softening UK drugs legislation, unchanged for 43 years
The camera is turned on tabloid editors in Richard Peppiatt's 'One Rogue Reporter'

Gotcha! The camera is turned on tabloid editors

Hugh Grant says Richard Peppiatt's 'One Rogue Reporter' documentary will highlight issues raised by Leveson
Fall of the Berlin Wall: It was thanks to Mikhail Gorbachev that this symbol of division fell

Fall of the Berlin Wall

It was thanks to Gorbachev that this symbol of division fell
Halloween 2014: What makes Ouija boards, demon dolls, and evil clowns so frightening?

What makes ouija boards and demon dolls scary?

Ouija boards, demon dolls, evil children and clowns are all classic tropes of horror, and this year’s Halloween releases feature them all. What makes them so frightening, decade after decade?
A safari in modern Britain: Rose Rouse reveals how her four-year tour of Harlesden taught her as much about the UK as it did about NW10

Rose Rouse's safari in modern Britain

Rouse decided to walk and talk with as many different people as possible in her neighbourhood of Harlesden and her experiences have been published in a new book
Welcome to my world of no smell and odd tastes: How a bike accident left one woman living with unwanted food mash-ups

'My world of no smell and odd tastes'

A head injury from a bicycle accident had the surprising effect of robbing Nell Frizzell of two of her senses

Matt Parker is proud of his square roots

The "stand-up mathematician" is using comedy nights to preach maths to big audiences
Paul Scholes column: Beating Manchester City is vital part of life at Manchester United. This is first major test for Luke Shaw, Angel Di Maria and Radamel Falcao – it’s not a game to lose

Paul Scholes column

Beating City is vital part of life at United. This is first major test for Shaw, Di Maria and Falcao – it’s not a game to lose
Frank Warren: Call me an old git, but I just can't see that there's a place for women’s boxing

Frank Warren column

Call me an old git, but I just can't see that there's a place for women’s boxing
Adrian Heath interview: Former Everton striker prepares his Orlando City side for the MLS - and having Kaka in the dressing room

Adrian Heath's American dream...

Former Everton striker prepares his Orlando City side for the MLS - and having Kaka in the dressing room
Simon Hart: Manchester City will rise again but they need to change their attitude

Manchester City will rise again but they need to change their attitude

Manuel Pellegrini’s side are too good to fail and derby allows them to start again, says Simon Hart
Isis in Syria: A general reveals the lack of communication with the US - and his country's awkward relationship with their allies-by-default

A Syrian general speaks

A senior officer of Bashar al-Assad’s regime talks to Robert Fisk about his army’s brutal struggle with Isis, in a dirty war whose challenges include widespread atrocities