NASA
NASA is Going Back to Venus. Here’s Why You Should Care.
Recently NASA announced two brand-spanking new missions to our sister planet, Venus. This is the first time in over 40 years that Americans have led a mission to that enigmatic planet. What do they hope to find? Clues to our past…and answers to our future.
Here’s the deal. Every star has what’s called a “habitable zone”, a region around that star where it’s not too hot to boil away water and where it’s not too cold to freeze it. It’s just the right balance to potentially find liquid water on the surface of a planet, and where you find liquid water you find the chance for life.
Earth is in the habitable zone of the sun. Earth is full of liquid water. Earth is full of life.
NASA
This picture of Earth is sometimes called the Blue Marble.
Venus is also in the habitable zone of the sun. Venus is full of rocks. Venus is very, very dead.
NASA
The northern hemisphere is displayed in this global view of the surface of Venus.
What happened? We think that billions of years ago Venus was just as cozy as the Earth, but it experienced a runaway greenhouse event. As the atmosphere piled up, the oceans boiled and the planet choked itself to death. Today, Venus boasts the hottest surface temperatures in the solar system – it’s literally hot enough there to melt lead.
If Venus once hosted life, it’s not having such a great time anymore.
Exactly how this process played out and when it all went down is a major mystery. We’re also not sure how much water splashed around on Venus back in the good old days, and how much might remain in its atmosphere today.
NASA
On Feb. 5, 1974, NASA's Mariner 10 mission took this first close-up photo of Venus. Made using an ultraviolet filter in its imaging system, the photo has been color-enhanced to bring out Venus's cloudy atmosphere as the human eye would see it. Venus is perpetually blanketed by a thick veil of clouds high in carbon dioxide and its surface temperature approaches 900 degrees Fahrenheit.
And as human activity continues to warm up our own planet, we can look to our (twisted) sister for implications of what uncontrolled greenhouse cycles can do to a planet.
So we’ve got two new missions. One mission, DAVINCI+ (Deep Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging), will descend through the cloudtops, sampling the Venusian atmosphere and taking pictures of the surface. Among its targets is to get a better handle on “tesserae”, which are strange features in the crust in the planet that might be comparable to our own planet’s plate tectonics.
NASA GSFC visualization by CI Labs Michael Lentz and others
DAVINCI+ will send a meter-diameter probe to brave the high temperatures and pressures near Venus’ surface to explore the atmosphere from above the clouds to near the surface of a terrain that may have been a past a continent. During its final kilometers of free-fall descent (shown here), the probe will capture spectacular images and chemistry measurements of the deepest atmosphere on Venus for the first time.
The second mission, VERITAS (Venus Emissivity, Radio Science, InSAR, Topography, and Spectroscopy), will orbit that hell-world from a safe distance, using radar to provide detailed maps of the surface. The VERITAS team hopes to find out if Venus still has active volcanos (which is a…wait for it…hot topic in astronomy right now). They also to figure out what kinds of rocks make up the surface of the planet.
NASA/JPL-Caltech/Peter Rubin
An artist's concept of active volcanos on Venus, depicting a subduction zone where the foreground crust plunges into the planet's interior at the topographic trench.
These two missions won’t answer all our questions about Venus, but it’s a start. Venus has intrigued scientists for decades, ever since we realized just how much it went down the wrong path in life.
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