Vénus - ESA's Venus Monitoring Camera

[Luis França]

Mysterious Haze Found on Venus

Venus’s atmosphere, taken by the Venus Monitoring Camera (VMC) during Venus Express
orbit number 459 on 24 July 2007. The view shows the southern hemisphere of the planet.
Credit: ESA/ MPS/DLR/IDA

The European Space Agency's Venus Monitoring Camera (VMC) captured a series of images showing the development of a bright haze over the southern latitudes of the planet in July 2007. Over a period of days, the high-altitude veil continually brightened and dimmed, moving towards equatorial latitudes and then back towards the south pole.

These transient dark and bright markings indicate regions on the cloud-covered world where solar ultraviolet radiation is being absorbed and reflected by sulfuric acid particles, mission scientists said this week.

Gaseous sulfur dioxide and small amounts of water vapor are usually found below altitudes of about 43 miles (70 kilometers) in Venus' carbon-dioxide rich atmosphere. These molecules are usually shrouded from view by cloud layers above that block our view to the surface at visible wavelengths.

 

[Luis França]

Venus mysteries blamed on colossal collision

Astronomers have spent decades trying to explain Venus' mysterious properties. Now one scientist thinks the planet's formation may explain all: Two huge, protoplanetary bodies collided head-on and merged to form our planetary neighbor, but obliterated nearly all water in the process.

"The probability that two protoplanets collided to form Venus is not at all implausible," said John Huw Davies, a geodynamicist at Cardiff University in the U.K. who developed the idea.

A majority of scientists think Earth's moon formed when a protoplanet about the size of Mars smacked into the planet at an angle. Davies thinks Venus was born of a far worse cosmic train wreck.

"What if the moon-Earth collision isn't that big in planetary terms?" Davies told SPACE.com. "A head-on blow between two similarly sized bodies would have been about twice as energetic."