Venus on acid

Bad Astronomy
The entire universe in blog form
Feb. 22 2008 9:35 AM

Venus on acid

Some people call Venus our sister planet, but if it is, it's the sister that went very, very bad.

The atmospheric pressure at the surface is a crushing 90 atmospheres. The surface temperature is 470 Celsius (about 900 F). The atmosphere is almost entirely carbon dioxide, and it rains sulphuric acid. To paraphrase Chekov, it's not exactly a garden spot.*

Phil Plait Phil Plait

Phil Plait writes Slate’s Bad Astronomy blog and is an astronomer, public speaker, science evangelizer, and author of Death From the Skies!  

Advertisement

Through a telescope (and by eye for that matter) Venus is beautiful and bright, but featureless. In visible light, the best you can see are very subtle patches on the disk of the planet. The atmosphere is far too thick to see the surface.

But there's still a lot to learn from the planet. The European Space Agency's Venus Express orbiter arrived at the hellish planet in April 2006 and set up shop. It's equipped with an ultraviolet camera, and when viewed in UV Venus is a whole 'nuther place. The chemicals in the atmosphere reflect or absorb UV from the Sun ,creating beautiful global weather patterns reminiscent of Earth's. Here's a recent UV shot:

As you can see, the story is different in UV than in visible. Things is, scientists aren't exactly sure what they're seeing. The bright stripes are due to sulphuric acid droplets in the air (yikes... I mean seriously, yikes). But they're not sure what's causing the darker regions; something is absorbing UV, but it's unknown exactly what it is.

And the weather on Venus is weird, too. The science team was recently amazed to see a bright haze form over the south pole of Venus, then, over the course of several days, grow to cover the southern half of the planet. Then, just as quickly, it receded. What could cause such a thing? No one knows. There are very small amounts of water vapor and sulphur dioxide in Venus's atmosphere, located deeper down (below 70 km in height). If this wells up, the ultraviolet from the Sun can break the molecules apart, which would reform into sulphuric acid, creating the haze. But why would those two molecules suddenly well up to the top of the atmosphere in the first place? Again, no one knows.

The only thing to do is keep looking. Venus Express has been orbiting the planet for nearly two years now, and that allows the long view, so to speak. By examining the data taken over long periods of time, scientists can investigate global properties of the planet and look for trends, connections, cause and effect. Venus has the same mass, size, and density of Earth, but at some point in its past it took a very different path than we did. Studying it carefully will reveal more about the Earth and why things turned out so well for us.

Sure, when you look into the abyss, sometimes it looks back into you. But that can be pretty helpful when you want to learn more about the abyss as well as yourself.


*What, you thought I meant Anton Chekov?

TODAY IN SLATE

Politics

Smash and Grab

Will competitive Senate contests in Kansas and South Dakota lead to more late-breaking races in future elections?

Stop Panicking. America Is Now in Very Good Shape to Respond to the Ebola Crisis.

The 2014 Kansas City Royals Show the Value of Building a Mediocre Baseball Team

The GOP Won’t Win Any Black Votes With Its New “Willie Horton” Ad

Sleater-Kinney Was Once America’s Best Rock Band

Can it be again?

Technocracy

Forget Oculus Rift

This $25 cardboard box turns your phone into an incredibly fun virtual reality experience.

One of Putin’s Favorite Oligarchs Wants to Start an Orthodox Christian Fox News

These Companies in Japan Are More Than 1,000 Years Old

Trending News Channel
Oct. 20 2014 6:17 PM Watch Flashes of Lightning Created in a Lab  
  News & Politics
Politics
Oct. 20 2014 8:14 PM You Should Be Optimistic About Ebola Don’t panic. Here are all the signs that the U.S. is containing the disease.
  Business
Moneybox
Oct. 20 2014 7:23 PM Chipotle’s Magical Burrito Empire Keeps Growing, Might Be Slowing
  Life
Outward
Oct. 20 2014 3:16 PM The Catholic Church Is Changing, and Celibate Gays Are Leading the Way
  Double X
The XX Factor
Oct. 20 2014 6:17 PM I Am 25. I Don't Work at Facebook. My Doctors Want Me to Freeze My Eggs.
  Slate Plus
Tv Club
Oct. 20 2014 7:15 AM The Slate Doctor Who Podcast: Episode 9 A spoiler-filled discussion of "Flatline."
  Arts
Brow Beat
Oct. 20 2014 9:13 PM The Smart, Talented, and Utterly Hilarious Leslie Jones Is SNL’s Newest Cast Member
  Technology
Technocracy
Oct. 20 2014 11:36 PM Forget Oculus Rift This $25 cardboard box turns your phone into an incredibly fun virtual reality experience.
  Health & Science
Medical Examiner
Oct. 20 2014 11:46 AM Is Anybody Watching My Do-Gooding? The difference between being a hero and being an altruist.
  Sports
Sports Nut
Oct. 20 2014 5:09 PM Keepaway, on Three. Ready—Break! On his record-breaking touchdown pass, Peyton Manning couldn’t even leave the celebration to chance.