Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Have Venusian volcanoes been caught in the act?

03.12.2012
Six years of observations by ESA’s Venus Express have shown large changes in the sulphur dioxide content of the planet’s atmosphere, and one intriguing possible explanation is volcanic eruptions.

The thick atmosphere of Venus contains over a million times as much sulphur dioxide as Earth’s, where almost all of the pungent, toxic gas is generated by volcanic activity.


Is Venus volcanically active?

Most of the sulphur dioxide on Venus is hidden below the planet’s dense upper cloud deck, because the gas is readily destroyed by sunlight.

That means any sulphur dioxide detected in Venus’ upper atmosphere above the cloud deck must have been recently supplied from below.

Venus is covered in hundreds of volcanoes, but whether they remain active today is much debated, providing an important scientific goal for Venus Express.

The mission has already found clues pointing to volcanism on geologically recent timescales, within the last few hundreds of thousands to millions of years.

A previous analysis of infrared radiation from the surface pointed to lava flows atop a volcano with a composition distinct from those of their surroundings, suggesting that the volcano had erupted in the planet’s recent past.

Now, an analysis of sulphur dioxide concentration in the upper atmosphere over six years provides another clue.

Immediately after arriving at Venus in 2006, the spacecraft recorded a significant increase in the average density of sulphur dioxide in the upper atmosphere, followed by a sharp decrease to values roughly ten times lower by today.

A similar fall was also seen during NASA’s Pioneer Venus mission, which orbited the planet from 1978 to 1992.

At that time, the preferred explanation was an earlier injection of sulphur dioxide from one or more volcanoes, with Pioneer Venus arriving in time for the decline.

“If you see a sulphur dioxide increase in the upper atmosphere, you know that something has brought it up recently, because individual molecules are destroyed there by sunlight after just a couple of days,” says Dr Emmanuel Marcq of Laboratoire Atmosphères, Milieux, Observations Spatiales, France, and lead author of the paper published in Nature Geoscience.

“A volcanic eruption could act like a piston to blast sulphur dioxide up to these levels, but peculiarities in the circulation of the planet that we don’t yet fully understand could also mix the gas to reproduce the same result,” adds co-author Dr Jean-Loup Bertaux, Principal Investigator for the instrument on Venus Express that made the detections.

Venus has a ‘super-rotating’ atmosphere that whips around the planet in just four Earth-days, much faster than the 243 days the planet takes to complete one rotation about its axis.

Such rapid atmospheric circulation spreads the sulphur dioxide around, making it difficult to isolate any individual points of origin for the gas.

Dr Marcq’s team speculate that if volcanism was responsible for the initial increase, then it could come from a relatively gentle increased output of several active volcanoes rather than one dramatic eruption.

“Alternatively, and taking into account the similar trend observed by Pioneer Venus, it’s possible that we are seeing decadal-scale variability in the circulation of the atmosphere, which is turning out to be even more complex than we could ever have imagined,” he notes.

“By following clues left by trace gases in the atmosphere, we are uncovering the way Venus works, which could point us to the smoking gun of active volcanism,” adds Håkan Svedhem, ESA’s Project Scientist for Venus Express.

Markus Bauer | EurekAlert!
Further information:
http://www.esa.int
http://www.esa.int/esaSC/SEM32XE16AH_index_0.html

Further reports about: ESA Venus Express Venusian active volcano upper atmosphere

More articles from Earth Sciences:

nachricht From volcano's slope, NASA instrument looks sky high and to the future
27.04.2017 | NASA/Goddard Space Flight Center

nachricht Penn researchers quantify the changes that lightning inspires in rock
27.04.2017 | University of Pennsylvania

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

Bare bones: Making bones transparent

27.04.2017 | Life Sciences

Study offers new theoretical approach to describing non-equilibrium phase transitions

27.04.2017 | Physics and Astronomy

From volcano's slope, NASA instrument looks sky high and to the future

27.04.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>