<optgroup id="euqu6"><div id="euqu6"></div></optgroup>
<center id="euqu6"></center>

Photo by: NASA/JPL


Is There Life on Venus? Something Smells Fishy…

Does the presence of a stinky gas mean there was once life on Venus?

September 14, 2020

Phosphine is one of the grossest chemicals out there. Not because of what it’s made of–one atoms of phosphorus and three atoms of hydrogen–but because it’s really, really stinky. It’s commonly associated with decaying organic matter, if you need a mental picture. It occurs naturally through a variety of processes, most notably as a byproduct of non-oxygen-using life. But since oxygen-using life is quite common on our planet, thankfully this stinky chemical is relatively rare.

Who Stank?



Phosphine or phosphane is the compound with the chemical formula PH3. It is a colorless, flammable, toxic gas and pnictogen hydride.

Photo by: ollaweila


Phosphine or phosphane is the compound with the chemical formula PH3. It is a colorless, flammable, toxic gas and pnictogen hydride.

Recently some astronomers have been raising a big stink (pun very much intended) about Earth’s sister planet, Venus. For those of you new to Venus: don’t go. It’s a nightmarish hellhole of a planet, choking on so much poisonous carbon dioxide that its surface pressure is over 90 times that of sea level. The temperatures at the surface are hot enough to melt lead. It rains sulfuric acid.

It’s nasty. And it just might–might – be a home for life.

A certain subgroup of astronomers known as astrobiologists (and yes, that’s a thing) are hunting for signs of life outside the Earth. One of the most promising ways is to look for (and this is a pretty awesome jargon word) biosignatures. These are signs of life in the form of chemicals that don’t normally come from chemical (i.e., boring unless you’re a chemist) processes.

An example of this is oxygen. The vast majority of the oxygen in our atmosphere comes as a byproduct of photosynthesis (in other words: life). If we were to find a lot of oxygen in another planet’s atmosphere, it just might be teeming with little critters.

Another potential biosignature is stinky molecule phosphine. Sure, it’s possible to create phosphine naturally, but it takes a lot of energy, and is very unstable–the UV radiation from the sun does a really good job at breaking it apart.

I’ll cut to the chase: a group of astronomers recently announced the presence of a load of phosphine in the atmosphere of Venus. A potential sign of life in basically the last place you would expect to find it.

Now we also see a lot of phosphine in the atmospheres of Jupiter and Saturn, and we really don’t think it comes from life on those giant planets–more likely it originates in some super-intense chemical process deep in their interiors.

But Venus?



Venus, computer artwork.

Photo by: SCIEPRO


The astronomers argue that they’ve thought of every possible way to make lots of phosphine in Venus without involving life, and keep coming up short.

Where could life exist in that hellscape? Well, a few dozen miles up in the atmosphere is pretty clement: room temperatures and standard air pressures. The air is still full of noxious carbon dioxide and sulfuric acid, but hey life has found footholds in stranger places.

But still, as with all stories of this nature, I urge caution and skepticism. Venus is a strange, strange environment that we barely even pretend to understand. Lots of crazy chemistry could be going on. There have been hints of life on Mars for decades that have been undermined by further study, and the same is likely true for Venus. By the time the news excitement dies down, there is likely to be a dozen hypothetical processes proposed that could explain the strange presence of phosphine on Venus.

Which is exciting if you’re into cool, weird chemistry, but not so exciting if you’re into life.

Paul M. Sutter

Paul M. Sutter is an astrophysicist at Stony Brook University and the Flatiron Institute, host of Ask a Spaceman and Space Radio, and author of How to Die in Space.

Next Up

Something Funky is Happening to the Earth’s Magnetic Field

Recently a weak spot in the Earth's magnetic field over the southern Atlantic Ocean has been getting weaker, which could signal the beginnings of a global magnetic reversal event. Or not. It’s complicated.

An Asteroid is Going to Kill Us All Before the Election... Or Not

So you may have heard the news by now that an asteroid is hurtling towards the Earth.

The First All-Female Spacewalk in NASA’s 61-Year History is Happening

"A-team" astronauts Christina Koch and Jessica Meir are set to make history in the first all-female spacewalk.

Waste In Space: NASA's Lunar Loo Challenge

Would YOU like to design one of the next toilets used in space?

NASA Astronauts Take on Two Spacewalks?at the International Space Station

Updated July 1, 2020 Six Days. Two spacewalks.?Both Successful.

NASA HQ to be Named in Honor of Mary W. Jackson

NASA announced Wednesday, June 24th that NASA's Washington, D.C. headquarters will now be named for Mary W. Jackson, the first black, female engineer at NASA.

NASA and SpaceX to Launch a Crewed Mission to ISS in May 2020

For the first time since its conception 18 years ago, SpaceX, along with NASA, will launch a crewed mission to space.

The Last Supermoon of the Year and How to See It

The Super Flower Moon of May is this year's last supermoon, when the Moon appears slightly larger and brighter in the sky because it is somewhat closer to Earth. Here's everything you need to know and how to watch it from home.

The Future of Space Exploration

Over the past couple decades, the space-minded folks around the world have debated the relative merits of the two possible destinations for space exploration. Moon or Mars?

NASA Astronaut Jeanette Epps Will Make History with Her Next Mission

It was announced this week that Astronaut Jeanette Epps will be added to NASA's Boeing Starliner-1 mission to the international Space Station. She will be the first Black astronaut to live on the ISS.
Related To: