I’m excited to announce that NASA has selected not one, but two possible missions to Venus as part of its studies for the next generation of robotic space probes.
I am beyond excited about this.
For as long as I can remember, Venus has been my favorite of the “Earth-like” planets in our solar system. This is due, in part, to its breathtaking spectacle in the night sky. If you are looking for something to wish upon, Venus will be the first “star” visible in the night sky for a few weeks. Right now, you can see it shining just after sunset in the southwestern sky. Just go outside right after dark and look to the south. You simply cannot miss it.
In fact, many folks mistake it for a supernova or alien spacecraft because its brightness is so shocking in the dim early night. But look through even a simple pair of binoculars, and you’ll see a cloudy surface half lit by the just-setting sun, which tells you that it is, in fact, a planet in our own solar system.
Venus is also very similar to Earth in both size and mass and only about 20% closer to the Sun. On the face of it, it seems as if Earth’s twin might be just a touch warmer than our home world. Up until the middle of the last century, some of the best minds on the planet imagined this cloud-enshrouded world as a jungle planet. I recall as a kid reading stories by Ray Bradbury about our own nearby Dagobah, and I while I haven’t asked him, I suspect George Lucas was inspired by the same stories.
Of course, the Soviet probes of the ’70s put that myth to bed. They discovered a hellish world with a surface temperature hot enough to melt lead and an atmospheric pressure similar to the bottom of the ocean.
It turns out Venus tells a cautionary tale of greenhouse warming. Early in its history, it may have been just a touch warmer than Earth and possibly even inhabited by early life forms. But this slightly warmer climate led the oceans to evaporate more quickly. All of that extra water vapor supercharged the atmospheric warming, leading to more evaporation and eventual loss of those early oceans. The lack of liquid water turned off the plate tectonics responsible for burying the carbon dioxide belched out by the very active volcanoes. As such, the planet just got hotter and hotter and hotter through a positive feedback that could not be stopped.
Today, Venus dissipates its interior heat by periodically burping molten rock across the entire surface, something that last happened over 700 million years ago. As such, we know next to nothing about early Venus beyond what our climate models can tell us, to the point that we are not even sure when Venus finally succumbed to its runaway greenhouse. It probably happened billions of years ago, but it could have happened anytime between then and the last volcanic resurfacing.
It’s the kind of stuff to make a scientist swoon.
Due to this hostile environment, Venus is chronically understudied. The reasons for this are many, but I’m of the opinion that Mars gets more interest because we can imagine eventually sending people to walk on its surface, allowing us to make a more compelling argument to the taxpayers.
If that’s the case, do I have a deal for you.
Due to Venus’ thick atmosphere, it would be possible to float a blimp in its upper reaches, where the temperature cools to nearly shirtsleeve weather. I imagine future respirator-clad “stratonauts” performing experiments like modern oceanographers, dropping experiments off the side of their semi-rigid dirigibles, and hauling up samples and other scientific data.
In the evening, they would retire to the blimp’s lounge, sipping cocktails while someone played the piano. Just like I imagine they do in those airships I read about in my steampunk novels.
In other words, science in the lap of luxury.
Of course, the current Phase A missions to study Venus won’t be looking into sending humans, instead focusing on short robotic excursions of the surface and orbital studies of the atmosphere. But I am very pleased to see Venus getting some much overdue love from NASA.
Still, for my money, you can keep your dust storms and frozen wastes of the red planet. Sign me up for a tour on one of Venus’ ships in the clouds!