Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Team led by scientists from University of the Basque Country manage to measure wind details of Venus

03.09.2008
Venus is a planet similar in size to the Earth. Nevertheless, it is quite different in other aspects.

On the one hand, it spins very slowly on its axis, taking 224 terrestrial days and, moreover, it does so in the opposite direction to that of our planet, i.e. from East to West.

Its dense atmosphere of carbon dioxide with surface pressures 90 times that of Earth (equivalent to what we find at 1000 metres below the surface of our oceans), causes a runaway greenhouse effect that raises the surface temperatures up to 450ºC, to such as extent that metals like lead are in a liquid state on Venus. At a height of between 45 km and 70 km above the surface there are dense layers of sulphuric acid clouds totally covering the planet.

It was in the 1960s that they discovered, by means of telescopic observations, that the top level of cloud layers moved very rapidly, orbiting the planet in only four days, compared to the planet’s own orbit of 224 days. This phenomenon was baptised the “superotation” of Venus: the winds carrying these clouds travel at 360 km/h.

The various space missions that explored the planet in the 70s and 80s showed that the “superotation” was a permanent phenomenon and, moreover the probes that descended through its atmosphere indicated that, in a number of places, the winds decreased in speed to zero at Venus’s surface. New observations carried out with the Venus Express mission of the European Space Agency, in orbit around Venus since April 2006, have enabled the team of scientists from the University of the Basque Country (UPV/EHU) to determine in detail the global structure of the winds on Venus at its level of clouds while, at the same time, to observe unexpected changes in the wind speeds, and which helped to interpret this mysterious phenomenon.

The team was led by Agustín Sánchez Lavega with team members being Ricardo Hueso, Santiago Pérez Hoyos and Javier Peralta, from the Planetary Sciences Group at the Higher Technical Engineering School of Bilbao. The article, entitled “Variable winds on Venus mapped in three dimensions”, was published with front page coverage in the Geophysical Research Letters. This journal is published by the US American Geophysical Union (AGU) and is the most prestigious in its sphere of research. Moreover, the article was one of eight selected amongst hundreds for publication by the AGU in all journals as being the most outstanding in the EOS Transactions bulletin – sent to 50,000 AGU members at research centres all over the world.

Novel aspects of the rotation

Using images recorded by both day and night on Venus with the VIRTIS spectral camera on board the Venus Express, the UPV/EHU scientists have succeeded in measuring these clouds over several months and have discovered new aspects of the “superotation”. Firstly, between the equator and the median latitudes of the planet there dominates a superotation with constant winds blowing from East to West, within the clouds decreasing speed with height from 370 km/h to 180 km/h. At these median latitudes, the winds decrease to a standstill at the pole, where an immense vortex forms.

Other aspects of the superrotation that observations with VIRTIS have made possible are that the meridional (North – South) movements are very weak, about 15 km/h, and, secondly, unlike what was previously believed, the superotation appears to be not so constant over time: “We have detected fluctuations in its speed that we do not yet understand”, stated the scientists. Moreover, for the first time they observed “the solar thermal tide” effect at high latitudes on Venus. “The relative movement of the Sun on the clouds and the intense heat deposited on them makes the superotation more intense at sunset than at sunrise”, they stated.

“Despite all the data brought together, we are still not able to explain why a planet than spins so slowly has hurricane global winds that are much more intense than terrestrial ones and are, moreover, concentrated at the top of its clouds” stated Mr Sánchez Lavega. This study has enabled advances to be made in a precise explanation of the origin of superotation in Venusian winds as well as in the knowledge of the general circulation of planetary atmospheres.

Irati Kortabitarte | alfa
Further information:
http://www.elhuyar.com
http://www.basqueresearch.com/berria_irakurri.asp?Berri_Kod=1855&hizk=I

More articles from Physics and Astronomy:

nachricht MEMS chips get metatlenses
21.02.2018 | American Institute of Physics

nachricht International team publishes roadmap to enhance radioresistance for space colonization
21.02.2018 | Biogerontology Research Foundation

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

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

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Researchers invent tiny, light-powered wires to modulate brain's electrical signals

21.02.2018 | Life Sciences

The “Holy Grail” of peptide chemistry: Making peptide active agents available orally

21.02.2018 | Life Sciences

Atomic structure of ultrasound material not what anyone expected

21.02.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>