[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

NASA-Funded Research Suggests Venus is Geologically Alive



April 8, 2010

Dwayne Brown 
Headquarters, Washington 
202-358-1726 
dwayne.c.brown@xxxxxxxx 

Jia-Rui C. Cook 
Jet Propulsion Laboratory, Pasadena, Calif. 
818-354-0850 
jia-rui.c.cook@xxxxxxxxxxxx 

RELEASE: M10-081

NASA-FUNDED RESEARCH SUGGESTS VENUS IS GEOLOGICALLY ALIVE

WASHINGTON -- For the first time, scientists have detected clear signs 
of recent lava flows on the surface of Venus. 

The observations reveal that volcanoes on Venus appeared to erupt 
between a few hundred years to 2.5 million years ago. This suggests 
the planet may still be geologically active, making Venus one of the 
few worlds in our solar system that has been volcanically active 
within the last 3 million years. 

The evidence comes from the European Space Agency's Venus Express 
mission, which has been in orbit around the planet since April 2006. 
The science results were laid over topographic data from NASA's 
Magellan spacecraft. Magellan radar-mapped 98 percent of the surface 
and collected high-resolution gravity data while orbiting Venus from 
1990 to 1994. 

Scientists see compositional differences compared to the surrounding 
landscape in three volcanic regions. Relatively young lava flows have 
been identified by the way they emit infrared radiation. These 
observations suggest Venus is still capable of volcanic eruptions. 
The findings appear in the April 8 edition of the journal Science. 

"The geological history of Venus has long been a mystery," said Sue 
Smrekar, a scientist at NASA's Jet Propulsion Laboratory in Pasadena, 
Calif., and lead author of the paper describing the work. "Previous 
spacecraft gave us hints of volcanic activity, but we didn't know how 
long ago that occurred. Now we have strong evidence right at the 
surface for recent eruptions." 

The volcanic provinces, or hotspots, on which Smrekar and her team 
focused are geologically similar to Hawaii. Scientists previously 
detected plumes of hot rising material deep under Venus' surface. 
Those plumes are thought to have produced significant volcanic 
eruptions. Other data from the planet suggest that volatile gases 
commonly spewed from volcanoes were breaking down in its atmosphere. 
The rate of volcanism will help scientists determine how the interior 
of the planet works and how gases emitted during eruptions affect 
climate. 

Something is smoothing Venus' surface because the planet has only 
about 1000 craters, a relatively small amount compared to other 
bodies in our solar system. Scientists think it may be the result of 
volcanic activity and want to know if it happens quickly or slowly. 
The Venus Express results suggest a gradual sequence of smaller 
volcanic eruptions as opposed to a cataclysmic volcanic episode that 
resurfaces the entire planet with lava. 

Smrekar and her team also discovered that several volcanic features in 
the regions they studied show evidence of minerals found in recent 
lava flows. These mineral processes correspond to the youngest 
volcanic flows in each region, giving scientists additional support 
for the idea they formed during recent volcanic activity. On Earth, 
lava flows react rapidly with oxygen and other elements in the 
atmosphere when they erupt to the surface. On Venus, the process is 
similar, although it is more intense and changes the outer layer more 
substantially. 

Scientists call Venus Earth's sister planet because of similarities in 
size, mass, density and volume. Scientists deduce that both planets 
shared a common origin, forming at the same time about 4.5 billion 
years ago. Venus also is the planet on which the runaway greenhouse 
effect was discovered. The planet is cloaked in a much less friendly 
atmosphere than Earth. It is composed chiefly of carbon dioxide, 
which generates a surface temperature hot enough to melt lead and a 
surface pressure 90 times greater than that on Earth. 

The small group of worlds in our solar system known to be volcanically 
active today includes Earth and Jupiter's moon Io. Crater counts on 
Mars also have suggested recent lava flows. Scientists are studying 
evidence of another kind of active volcanism that involves 
ice-spewing volcanoes on other moons in our solar system. 

NASA sponsored Smrekar's research. The European Space Agency built and 
manages Venus Express. 

To view the spacecraft data and images, visit: 



http://www.nasa.gov/topics/solarsystem/features/magellan20100408.html 

	
-end-



To subscribe to the list, send a message to: 
hqnews-subscribe@xxxxxxxxxxxxxxxxxxxxxx
To remove your address from the list, send a message to:
hqnews-unsubscribe@xxxxxxxxxxxxxxxxxxxxxx
[JPL News]     [Cassini News From Saturn]     [NASA Marshall Space Flight Center News]     [NASA Science News]     [James Web Space Telescope News]     [Cassini]     [Science Toys]     [JPL Home]     [NASA KSC]     [NTSB]     [Deep Creek Hot Springs]     [Hot Spring Photos]     [Yosemite Camping]     [Yosemite Discussion]     [NSF]     [Bake Sale for NASA]     [Telescopes]


Powered by Linux