A Stanford researcher is growing crystals on the International Space Station and electronics to withstand the extreme environments of Venus.
Debbie Senesky: Venus is often called Earth's sister planet, but I would like to say that it's Earth's evil twin because it actually has a very hellish environment. Surface temperatures are around 480 degrees Celsius. The surface pressures are roughly 90 times the pressure that we experience here on Earth. And I imagine that it smells like rotten eggs and that's because of some of the sulfur compounds that are present.
It's hypothesized that billions of years ago Venus looked like Earth. Why did that evolution take place? Are there things that we can learn about Venus's history that we can apply in understanding of Earth's environment so we can prevent our own planet from evolving to have those kinds of conditions via climate change?
My name is Debbie Senesky, and I'm an Associate Professor at Stanford University in the Aeronautics and Astronautics Department.
You are sitting in the extreme Environment Microsystems Laboratory or the X Lab at Stanford University. And in this lab, we research tiny but tough electronics and materials for space exploration. To enable electronics to work on Venus, my group uses wide bandgap semiconductor materials.
These are essentially ceramic materials, just like your pots and pans, and they can sustain high temperatures, but they can also conduct electrons in a very reliable fashion. So you can use these ceramic semiconductor materials to make electronics that you might use for sensors or communication in a Venus environment.
It is still a challenge to make electronics out of these types of semiconductor materials. We have a hard time growing these materials without defects. We have a hard time understanding how they function within these high temperature and chemically corrosive environments.
A new thing that my group is working on is harnessing the space environment to make new types of materials. Chemistry happens differently in microgravity. You can potentially get materials with new properties that you cannot achieve here on Earth. Microgravity is different from Earth based processing because we eliminate a lot of the effects that we see here on Earth.
Number one is sedimentation. So, for example, if you had a Turkish coffee, on Earth, particles would sink down to the bottom of your cup and then you would drink your nice tasty coffee on top. However, if you brought your Turkish coffee up to low Earth orbit you would have your coffee grinds free floating and you would have a mouth full of coffee grinds when you took a sip. So it's not great for making coffee, but it is great for making new materials in space.
Over 20 years ago, when we were conducting microgravity growth of materials on the space shuttle, we found that the materials had better quality, so less defects, and they also grow at faster rates. So we can make things better and faster if we manufacture them in space.
So one of our first experiments to be conducted in low Earth orbit on the International Space Station is to synthesize graphene aerogels materials. They're very lightweight, highly porous, they're electrically conductive and also thermally insulating. These materials are great because they can be used as heat shields, they can be used as battery electrodes and also sensor materials. They would have more uniform properties by manufacturing them in a microgravity environment.
In space manufacturing is not science fiction. Access to space is becoming more and more frequent. We call them the CLDs: Commercial Low-Earth orbit Destinations. These will be platforms that are very similar to the International Space Station, but created by commercial industry. Maybe we'll be manufacturing new types of crystals that we never dreamed of. Also, we'll be using these factories to create things that we might use for space missions.
It is a new space economy, the new frontier. We're really rethinking the way we might live 50 years from now.