From Science @NASA Japanese Spacecraft Approaches Venus
For the next few months, Venus will be softly resplendent in the evening sky, a treat for stargazers – but looks can be deceiving.
Consider this: The Venusian surface is hot enough to melt lead. The planet’s 96% carbon dioxide atmosphere is thick and steamy with a corrosive mist of sulfuric acid floating through it. The terrain is forbidding, strewn with craters and volcanic calderas – and bone dry. Takeshi Imamura can’t wait to get there.
Imamura is the project scientist for Akatsuki, a Japanese mission also called the Venus Climate Orbiter. The spacecraft is approaching Venus and will enter orbit on December 7, 2010. Imamura believes a close-up look at Venus could teach us a lot about our own planet.
“In so many ways, Venus is similar to Earth. It has about the same mass, is approximately the same distance from the sun, and is made of the same basic materials,” says Imamura. “Yet the two worlds ended up so different. We want to know why.”
Although a parade of U.S. and Soviet spacecraft has visited Venus since 1961, no one yet knows how it became Earth’s “evil twin.” Did it suffer from a case of global warming run amok – or something else? When Akatsuki reaches Venus in December, it will begin to solve some of the mysteries hidden in the thick Venusian atmosphere.
“By comparing Venus’s unique meteorology to Earth’s, we’ll learn more about the universal principles of meteorology and improve the climate models we use to predict our planet’s future.”
Particularly puzzling is Venus’s “super-rotation.” Fierce, blistering winds propel an atmosphere filled with storms and sulfuric acid clouds in a churning maelstrom around Venus at over 220 miles per hour, 60 times faster than the planet itself rotates.
“Venus’s atmosphere is in perpetual motion, as if a living thing,” says Imamura.
Within this swirling cauldron are other Venusian riddles to be solved: What is the origin of the 12-mile thick layer of sulfuric acid clouds that shrouds the planet? And how does Venus’ lightning crackle through this strange brew?
Akatsuki, bristling with cameras, will circle the exotic planet’s equator in an elliptical orbit for at least 2 years, monitoring the atmosphere at different altitudes using various wavelengths (IR, UV, and visible). With this data and data from the spacecraft’s radio dish, scientists will reconstruct a 3D model of the atmosphere’s structure and dynamics.
“The spacecraft’s orbit will match the circulation of Venus’s clouds, allowing the instruments to monitor cloud movement from directly above for 20 hours at a time. We’ll assemble the images to produce a cloud motion time-lapse movie, much like a weather forecaster on television might show you of Earth.”
The instruments will also scrutinize the planet’s surface for volcanic activity that could be contributing to the sulfur contents of the atmosphere. “If any active volcanoes are spouting hot lava on Venus, one of our infrared cameras will detect the thermal emission,” says Imamura.
In addition, Akatsuki’s Lightning and Airglow Camera will hunt for lightning in order to settle a longstanding debate. “On Earth, the standard theory of lightning requires water ice particles on which positive or negative charges are induced via collisions,” explains Imamura. “But there are no ice particles in Venus’s hot, dry atmosphere–so how does Venusian lightning get started? It may be that charge separation can occur in sulfuric acid clouds–or perhaps some unknown solid particles exist in the atmosphere and play an important role.”
Imamura can scarcely contain his curiosity. “As a young boy I loved to watch clouds, stars, oceans, rocks, and creatures. I wanted to understand why they look and behave as they do. Now I am curious in the same way about Venus. Nature is so full of mysteries!”
Beginning in December, some of Venus’s mysteries will be revealed. Stay tuned.
Cytherean.
mecago says:
August 17, 2010 at 11:29 am
I think there’s something wrong in that calculation. Mercury is half the distance to the Sun than Venus and therefore gets four times the radiance but it’s only 427C.
Mercury, like Earth, has a magnetosphere, Venus has not magnetic field (magnetosphere). That’s the difference.
The high temperatures at Venus surface, not Venusian atmosphere, makes the carbon dioxide volume expands such that the CO2 molecules become separated one to the other at distances that impedes them to interact efficiently with IR photons.
The average surface temperature on Venus is always, day and night, higher than its average atmospheric temperature. Therefore, the thermal energy always is transferred from the surface to the atmosphere, not the opposite way.
The formula to calculate the incident solar energy upon any planet of the solar system is as follows:
GPL = QSUN / 4π (POR)^2
Where, GPL is the amount of incident solar radiation upon the planet, QSUN is the total amount of energy emitted by the Sun expressed in Watts (3.94832e+26 W), 4π = 12.56637061, and POR is the Planet Orbital Radius, expressed in meters.
Buffoon says:
“I think ““In so many ways, Venus is similar to Earth. It has about the same mass, is approximately the same distance from the sun, and is made of the same basic materials,” is perfectly acceptable, especially considering””
This is ignoring the well-known inverse square law. Venus, at 2/3 approx. the distance from the sun receives 1/(67squared/93squared) = 1.92 times the energy per square metre.
>> Ric Werme says:
August 17, 2010 at 10:20 am
With Venus’s slow rotation rate, it would take a rather distant orbit. It may be that the “20 hours” mentioned above is for the far end of the orbit. The inner part would zoom by real quick before the apparent motion slows down on the next outward climb. <<
According to the article, the spacecraft orbits at cloud speeds, about 220 miles per hour. That's still only about 1/4 of the rotation rate of the Earth, so the spacecraft orbital semimajor axis would have to be significantly farther than Geosynch on Earth.
A satellite in an elliptical orbit must be travelling faster at closest approach (perivenera?) than a satellite in circular orbit at that distance in order for the elliptical satellite to move significantly farther away at 'apvenera'. So tracking the clouds at 'perivenera' couldn't last 20 hours, and must be done at 'apvenera' as you stated.
So this would be all right by you:
“We have sent a probe to see why Anchorage, Alaska is so different in climate from Miami, Florida, when both are so similar in size and have hard dirt surfaces. There are, of course, differences.”
To follow up on the point made by asmilwho: “This is ignoring the well-known inverse square law. Venus, at 2/3 approx. the distance from the sun receives 1/(67squared/93squared) = 1.92 times the energy per square metre.”
The albedo (reflectance) of Earth is 0.367 and that of Venus (all-spectrum) is 0.75. This means that the effective solar irradiance into Venus’s atmosphere (and ultimately to its surface) is about 76% of that of Earth! WUWT?
I think it was JBS Haldane who said “The universe is not only queerer than we suppose, it is queerer than we can suppose.”
John Lohman says ‘Japan? December 7th?’
Well – look at that photo : looks just like a giant Pearl to me!
Tom_R says:
August 17, 2010 at 11:31 am
To me this implies that the Earth is pretty good at eliminating CO2 quickly, and that also jibes with discrepancy between human CO2 output and atmospheric increase.
“Discrepancy” you say? I don’t know how to drive tanks but I could drive one through that analogy.
If you do some basic research you’ll find out that the Oceans account for that discrepancy.
How have you quantified this? Taking your word that Earth is much quicker than Venus at sequestering Carbon Dioxide, which I agree with by the way, how quick is quick?
Back to how quick or fast this “Earth is pretty good at eliminating CO2 quickly”, any Climatologist could tell you that. But please tell me if it’s fast enough to:
1) Fast enough to prevent an extra 1F of Globally averaged heat, on top of the 1.4F that we already have, that is due to us in the next 30 years from Thermal Lag? This assuming that we stop burning ALL fossil fuels today?
2) Fast enough to counterbalance that most ironic postponing event called Global Dimming? Before the aerosols, that came from the same combustion as the CO2 did, filter down from the sky due to a massive decrease in our wretched and meaningless industrial ECONOMY (Blessed be its Name)?
3) Fast enough to reverse the effects of an open Arctic in warming the Northern Hemisphere by yet another degree?
I don’t think so. In any case Climatologists have done the math but then, as this website “metaphorically” described them, they’re just a bunch of Roaches.
I apologize in advance for posting a self-promotion again. I don’t like to do this, but there are many not known things on the “morning star” physics. For example, the effect of volumetric expansion of the Venusian carbon dioxide on its absorptivity and emissivity and other features. In my opinion, if JAXA research goes “untouched” on ground, it will find what the theory predicts.
More on Venus here:
http://climaterealists.com/index.php?id=6153
Nasif Nahle says:
August 17, 2010 at 11:45 am
The average surface temperature on Venus is always, day and night, higher than its average atmospheric temperature. Therefore, the thermal energy always is transferred from the surface to the atmosphere, not the opposite way.
If “thermal energy always is transferred from the surface to the atmosphere,” where does that energy come from?
Wikipedia says, “The permanent cloud cover means that although Venus is closer than Earth to the Sun, the Venusian surface is not as well lit.” () Does enough radiant energy reach the ground to continuously maintain its temperature above the temperature of the atmosphere?
Will Venus become the poster child for the CO2 crowd?
Frank Lee MeiDere says:
August 17, 2010 at 11:43 am
🙂 Learn something new every day! Thanks for the link and the lesson.
Various commenters were puzzling over why there is no water on Venus. Actually, there is. Water (H2O) + sulfur trioxide (SO3) = sulfuric acid (H2SO4), a process that takes place at high pressure and temperature. It worked well enough for the pulp mill in my home town, which burned sulfur to the trioxide and ran it through water-bath reactor columns to form the sulfuric acid needed to dissolve wood pulp. If you can estimate how much sulfuric acid is in the atmosphere of Venus, you can estimate the latent water content.
Two thought occurred to me immediately when I read this, but I got beaten to the punch on both and they are right next to each other 🙂
#
Ed Murphy
August 17, 2010 at 8:06 am
I think Earth was fortunate enough to be struck by a huge comet when the moon was formed
#
John Lohman
August 17, 2010 at 8:07 am
Japan? December 7th?
———————————————————————————
Our moon makes us very special!
I bet the Venusians don’t expect a thing. hehehe
Jini tsuki shichi nichi, nihon wa kinboshi ni ….
Why do I have this fear that they ‘will use climatology to fill in the blanks’ running through my mind?
The two greatest difference between the Earth’s and Venus’s weather / climate are the Earth’s oceans and moon. I can’t for them to figure out how much that means to the Earth.
It’s what I do 🙂
To tell the truth, I read that in a science book when I was about ten years old and although I can’t say I’ve ever seen it used since, for some reason the word stuck with me.
Now the names of my grandchildren — that’s a different matter.
A refrigerator is similar to an oven because both have a rectangular shape, a door and a light (although one cannot be sure the refrigerator light ever goes out). So if we study an oven we will know how a refrigerator works.
“They are about the same size” (not)
“They are about the same distance from the sun” (not)
That’s the kind of generalization that promotes clueless politicians believing James “Dr. Venus” Hansen saying our.o3 percent CO2 will be 96 percent tomorrow if we don’t start living like it’s 1450.
Over at “Sea Ice News #18” the text of the whole post suddenly went boldface midway through a comment by:
mecago on August 16, 2010 at 10:41 am
and stayed that way to the end of the page, until it was later corrected.
Now I am seeing italicized text in this article starting above at:
mecago on August 17, 2010 at 1:04 pm
midway through that comment and running through this entire post to the end of this page.
Let me take a wild flying guess here, and surmise someone is messing up the posts by using bold and italics together without properly ending their use of the HTML attributes in their comments.
Colonial says:
August 17, 2010 at 1:16 pm
If “thermal energy always is transferred from the surface to the atmosphere,” where does that energy come from?
Wikipedia says, “The permanent cloud cover means that although Venus is closer than Earth to the Sun, the Venusian surface is not as well lit.” () Does enough radiant energy reach the ground to continuously maintain its temperature above the temperature of the atmosphere?
One obvious answer is “from the subsurface materials”. Another answer not so quite obvious, but that will be obvious after JAXA advances in their research, is the superheated plasma which strikes directly on the surface of Venus. Remember that Venus has not the protective magnetic field that Mercury and Earth have, i.e. a magnetosphere.
Michael J. Dunn says:
August 17, 2010 at 1:44 pm
Various commenters were puzzling over why there is no water on Venus. Actually, there is. Water (H2O) + sulfur trioxide (SO3) = sulfuric acid (H2SO4), a process that takes place at high pressure and temperature. It worked well enough for the pulp mill in my home town, which burned sulfur to the trioxide and ran it through water-bath reactor columns to form the sulfuric acid needed to dissolve wood pulp. If you can estimate how much sulfuric acid is in the atmosphere of Venus, you can estimate the latent water content.
Indeed, ESA has obtained images of the outer layer of the atmosphere of Venus where they detected water. The Venusian atmosphere has water vapor also. Nevertheless, Venus has not seawater.
The origin of SO3 could be intense volcanic activity, deduced from the electric discharges in the near to the surface layers of the atmosphere and the fluctuations of the Venusian cloud microphysics.
“”” Tom_R says:
August 17, 2010 at 11:31 am
>> “In so many ways, Venus is similar to Earth. It has about the same mass, is approximately the same distance from the sun, and is made of the same basic materials,” says Imamura. “Yet the two worlds ended up so different. We want to know why.” <<
Let me defend this statement. First off, astronomy deals with ballpark figures, so the distances 0.7 AU and 1.0 AU are very close in astronomical terms. The bigger equivalence goes back to the origin of both planets. The material that formed planets at 0.7 AU and 1.0 AU would be expected to be of similar composition. Venus gets twice the solar energy that Earth receives, does that alone explain the different evolution of the two worlds? """
Yes Tycho Brahe had it all wrong. If he had just said Venus is over there towards the sun, and Mercury is too; but usually closer; and Mars goes back wards sometimes; but only for a while so it mostly goes forwards, well I am sure the state of Astronomy would still be in great shape; well that's ball park great shape of course.
Now let me see the error in the rate of precession of the perihelion of Mercury predicted; excuse me that's projected; from classical Newtonian orbital theory, was a huge 43 seconds of arc per century ; well that's just ballpark mind you; so no reason to go off on a tangent and follow that Einstein idiot and his crazy theory about warped space time !
Izzere anything that is more "ballpark" than Climate science; well besides that ancient astrology that the Japanese are fond of mentioning ?
And be it known that I didn’t italicize any of that above either.
Why has everything suddenly gone Italic on me???
Spooky!!!
“Fierce, blistering winds propel an atmosphere filled with storms and sulfuric acid clouds in a churning maelstrom around Venus at over 220 miles per hour, 60 times faster than the planet itself rotates.”
The winds propel the atmosphere? How?