字幕列表 影片播放 列印英文字幕 A submarine that can dive through Titan’s methane seas. A celestial hopper that can harvest frozen nitrogen as propellant. These are the types of futuristic spacecraft that could explore distant worlds for us. But while they look straight from science fiction, there’s actually an in-house conceptual design team at NASA behind them. I'm Steve Oleson. I run the NASA COMPASS team. COMPASS was begun in 2006 during the Constellation program. We put the team together to basically design lunar landers. How do you get people down to the surface? How do you do it efficiently? While the Constellation program was cancelled by the Obama Administration, word got out about COMPASS’s expertise. This team can deliver a new spacecraft design and scope the costs in just two weeks. And it all starts with a wild idea. A new technologist will bring their new power system to us and say, "Here's a reactor. I want to put it on the moon. How would I package it? How would I land it? How would I operate it?" To us, every new environment, every new place to go requires a new vehicle. These vehicles, a lot of times, they are spacecraft, but there's other times, they're rovers and submarines. It's always something new, but we do about 16 designs a year. Our mantra is, "Base it on physics." There could be technologies that needed to be developed. We try to infuse those into our designs, but it's still something that is based on physics. There are so many different spheres of expertise that go into designing a new spacecraft — like propulsion, materials, software — and they’re all woven in simultaneously during the development process. Imagine something flying through space has to have obviously a structure to it. It's going to need power. You may be able to talk to it, right? You have the science instruments that gather data, so you got to send back the data with a communication system. We have to have some kind of radiator, so the thermal systems keep us at the right temperature, so that things don't get too hot, things don't get too cold. Of course, propulsion to get us to stop or start or go wherever we want to go. Finally, trajectories — so how do we get to there and get back again? Ultimately though, we want to lay this whole thing out, so we have a computer configuration. They look really great, and they could be feasible, but will it cost too much? Is this something that's affordable for this approach? We have people on the team to do all those things. To get all of these team members to work together, they really need to think outside the box. We do need them to know what the box is that they're trying to get out of, but communication is really the key. I'm like the game show host. One of my biggest roles is getting new creativity out of people. We often combine electric propulsion with chemical propulsion, which one would think, those are at odds with each other. But it turns out, chemical propulsion is really great when you're near a planetary body. Electric propulsion is fantastic in deep space. The technologies were already there, but how do you combine those together in a new way? That's the creativity. With all of these emerging discoveries, NASA’s problem isn’t trying to find places to go, it’s figuring out which place to go first. Titan is a wonderful place. It has a very thick atmosphere. Except for the temperature, if I put you on Titan in a spacesuit, you could put on some wings, and you could flap around and fly, because the gravity is so low, and the atmosphere is so dense…. you can splash down in the sea and become a submarine. So where do you even start when you have to conceptualize a submarine to float 1.27 billion kilometers away on one of Saturn’s Moon. The biggest challenge with the submarine was communications and basic going up and down. A boat just has to float, so we did ballast systems. The other big question was communications. It turns out that the liquid methane is actually radio transparent. Technically, if you have an orbiter above you, you can sit on the bottom, a kilometer deep, and talk through all that liquid methane. It's those fascinating things to us. It looks like a regular submarine, but we've got a lot of different things, because the environment, the physics are so different on that moon. Compass’s spacecraft designs are based off of the limited data we have so far of these worlds, and hopefully they’ll advance our understanding even further. There's Europa with the 20 kilometers of ice and what could be below in the ocean. We've designed a tunnel bot that would actually dig through there using a reactor to melt its way through. For the Venus land-sailing rover, we basically came up with a design that has a wing that you would just turn, and you would sail in the direction you want. Again, the high temperature electronics are key to making that thing work. Venus is a scorching 465 degrees Celsius, enough to melt most commercial electronics. To get this land sail to cruise, a team of scientists are working on new integrated circuits that can withstand those high temps. It's still in the conceptual design phases….You need to demonstrate the high temperature in electronics first, and that's what we're doing with some demonstrations, working that now. Once you get those, now you can start to explore. Because Compass has to dream up the impossible, it pushes other teams to invent new technologies that would power future missions. And that has major benefits for us here on Earth. A lot of things we've done have not flown yet, because it takes time. One of the greatest things that we did was this thing called Fetch, which basically was going to grab an asteroid, and we're talking something in, roughly, 10 meters diameter, actually grab that with this bag and use electric propulsion to push it back. This is one of the neatest things I think we've done, because this is completely out-of-the-box. Can you actually grab an asteroid and move it back? This project was part of Obama's Asteroid Retrieval Mission, which pledged to send astronauts to an asteroid by 2025. That mission was cancelled by Trump in 2017. We have a joke here at NASA, that every solar cycle or 11 years or so, we switch from going to Mars to the moon, and that's really what's happened. Bush said, "We're going back to the moon." Then, of course, Obama came in and said, "We're going to grab the asteroid, go to that." Now, Trump is here. Instead of grabbing the asteroid now, we're going to basically send a crew to orbit the moon. The same vehicle that we came up with in 2012 is now the power propulsion element for the Gateway. A lot of things evolved, and a one-week study evolved into now the power system and propulsion system for what the astronauts are going to ride on. At the heart of all of these designs, the COMPASS team enjoys the challenge. They’re taking futuristic, sci-fi designs and making them real. Science fiction has led the way in a lot of space exploration just with being able to think out-of-the-box. In fact, we have discussions on whether they're a Star Wars fan or a Star Trek fan, right? We all love those genres. We grew up on them.Seeing science fiction in the movies, reading the books, gives you that mindset that anything is possible, and that there are new worlds out there. The COMPASS team is developing new concepts, so the public can get a better window on all these things, see these new, fascinating things and maybe get a little better understanding of maybe how unique we are or how unique we aren't. For more science documentaries, check out this one right here. Don't forget to subscribe and keep coming back to Seeker for more videos.
B2 中高級 任務設計師如何發明未來主義的航天器? (How Mission Designers Invent Futuristic Spacecraft) 2 0 林宜悉 發佈於 2021 年 01 月 14 日 更多分享 分享 收藏 回報 影片單字