Tag: Venus

The strange polar vortexes of Venus.

9:54 am

The strange polar vortexes of Venus.

The large-scale cyclone extends vertically in Venus’ atmosphere over more than 20 kilometers, through a region of highly turbulent, permanent clouds. However, the centers of rotation at two different altitude levels (42 and 62 km above the surface) are not aligned and both wander around the south pole of the planet with no established pattern at velocities of up to 55km/h. The study also finds that even when averaged cross-winds are roughly the same at both altitudes, there is still a strong vertical gradient, with winds increasing by as much as 3km/h for every kilometer of height and leading to possible atmospheric instabilities.

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Changes in the levels of sulphur dioxide since Venus Express arrived in orbit around Venus in 2006 now suggest strongly that the spacecraft has detected volcanic activity on the planet.

7:46 am

Changes in the levels of sulphur dioxide (SO2) since Venus Express arrived in orbit around Venus in 2006 now suggest strongly that the spacecraft has detected volcanic activity on the planet.

The SPICAV data show that the concentration of SO2 above the main cloud deck increased slightly to about 1000 parts per billion by volume (ppbv) between 2006 and 2007, but then steadily decreased over the next five years, reaching only 100 ppbv by 2012. This is very reminiscent of a pattern observed by Pioneer Venus during the 1980s, the only other multi-year dataset of SO2 measurements.

One of best explanations for these changes is a volcanic eruption back in 2006, which would have inserted a great deal of SO2 into the upper atmosphere. Since then, ultraviolet radiation from the sun has steadily destroyed it.

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Despite lacking a magnetic field of its own, scientists have discovered magnetic storms surrounding Venus.1

11:45 am

Despite lacking a magnetic field of its own, scientists have discovered magnetic storms occurring in the space surrounding Venus.

The finding, reported today in Science1, suggests that magnetic reconnection may generate auroras on Venus, and could have contributed to the loss of a thick, water-rich atmosphere that scientists believe surrounded the planet during its early history, some 4 billion years ago.

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Is Venus’s day getting longer?

9:10 am

Is Venus’s day getting longer?

In the 1980s and 1990s, the Venera and Magellan orbiters made radar maps of the surface of Venus, long shrouded in mystery as well as a dense, crushing and poisonous atmosphere. These maps gave us our first detailed global view of this unique and hostile world. Over its four-year mission, Magellan was able to watch features rotate under the spacecraft, allowing scientists to determine the length of the day on Venus as being equal to 243.0185 Earth days. .

However, surface features seen by Venus Express some 16 years later could only be lined up with those observed by Magellan if the length of the Venus day is on average 6.5 minutes longer than Magellan measured. This also agrees with the most recent long-duration radar measurements from Earth.

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Akatsuki’s engine too damaged to put the probe into Venus orbit in 2015

9:23 am

The engine of Japan’s troubled Venus probe, Akatsuki, has been found too damaged to put the probe into Venus orbit.

JAXA conducted a test ignition of the probe’s main engine on Wednesday to prepare for another attempt to send it into orbit in 2015. But the thrust produced was only one-eighth the amount anticipated, the space agency said. The damage the engine suffered last December when JAXA ignited it in the initial attempt to send the probe into orbit around Venus appears to be more serious than thought, JAXA said.

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Scientists pinpoint where Venus’s sulphuric acid clouds come from

12:07 am

Apropos of the desire of IPCC chief Rajendra Pachauri to re-engineer the climate to battle global warming, including spraying “sulphate particles high in the atmosphere to scatter the sun’s rays back into space,” planetary scientists have pinpointed the source of Venus’s sulphuric acid clouds, and from this believe that the IPCC scheme might backfire badly, doing more harm than good.

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A wish list of spectacular future planetary missions

5:01 pm

Steve Squyres of Cornell University and the project scientist of the Mars rovers Spirit and Opportunity spoke today at an astrobiology symposium in Arlington, Virginia. He described several spectacular planetary missions that might be flown in the coming decade. All are being considered. None have yet been chosen or funded.

  • A mission to grab a sample from a comet and return it to Earth.

  • A mission to put a rover or lander on one of the poles of Mars to study the frozen layers of water under the icecap.

  • Mars sample return mission. This mission is so difficult and expensive that it probably would be broken down into three parts:

    • Two rovers on the surface to gather and cache sample material.

    • A lander/rover mission to grab the samples and bring them up to Mars orbit. “Putting into orbit a precious cargo the size of a coconut,” Squyres said.

    • A mission to grab the sample cargo in Martian orbit and return it to Earth.

  • An orbiter to study both Jupiter and its moon Europa.

  • An orbiter to Enceladus, the moon of Saturn, to study the water and organic chemistry in its mysterious plumes.

  • An orbiter to Titan, with balloon to probe the atmosphere as well as a “lake lander, a boat” to study Titan’s lakes.

  • A variety of landers and rovers to go to Venus. One of the more astonishing mission concepts would land, then take off again to visit different places on the surface.

Squyres is the co-chair of a committee of the National Science Foundation that is right now putting together a decadal survey for outlining unmanned planetary research for the next decade. This survey is expected to be released in March, which is when we will find out which of the above missions the planetary science community prefers.

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The atmosphere of Venus is 60% less dense at its poles

3:01 pm

By diving into the upper atmosphere of Venus above its north pole, Venus Express has found that the atmosphere there is 60% less dense than predicted. This from a press conference going on right now at the 42nd meeting of the AAS Division for Planetary Sciences. They plan an additional dive campaign during the next month. And they plan more dives, going deeper each time, as they judge the consequences to the spacecraft each time.

To read the abstracts of the Venus Express papers, go here.

Updated: The full press release, with images, can be seen here.

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The double vortex at Venus’s south pole is gone

2:57 pm

Using data accumulated over the past four years by Venus Express, scientists have shown that the giant double vortex storm at Venus’s south pole was only a temporary phenomenon. You can download the actual paper here [pdf]. Key quote from the paper:

The polar region of Venus shows a dynamics regime quite different than the rest of the planet, with a separation region delimited by the cold collar zone. Average wind speeds presents an almost solid body rotation, while instantaneous view highlights the complex dynamic structure with air flowing almost toward all directions. The so called dipole shape is not a stable feature and the morphology of the vortex is significantly variable on both short and long timescales.

The “cold collar” is an atmospheric ring of colder temperatures that encircles the planet’s poles.

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