Name: NASA's New Space Reactor Is Powered by Nuclear Fission
Uploaded: 2020-04-07T02:36:31.000Z
Duration: 7 min 7 s
Description: Thousands of YouTube videos with English-Chinese subtitles! Now you can learn to understand native speakers, expand your vocabulary, and improve your pronunciation...

Adverbs of degree

From a technology standpoint, there's not too many greater challenges than nuclear power

The physics involved in it is quite intense — it has that luster of something totally

We start with that highly enriched core, the splitting of the atoms generates that heat

that we need at the right power levels, at the right temperature levels, and then we

transfer that heat up to the power conversion system.

You convert that to electricity at that engine, reject some of the waste heat, and then use

the electricity for whatever you're trying to power, whether it's a coffee maker or a

It sounds pretty simple because it kind of is simple.

It's just the engineering pieces aren't always simple.

Nuclear energy and space flight have a deep history that stretches all the way back to

At the time, scientists were looking for new ways to harness the power of the atom, and

nuclear offered something special for deep-space missions.

When we go out in deep space or whether we're in a shadowed crater on the moon or whatever,

The secondary piece of that is the amount of power that energy can provide.

Fission power is very, very high on the power density scale.

As a quick refresher, nuclear fission releases heat energy by splitting atoms, and fusion

combines two lighter atoms into a larger one.

They both release an enormous amount of energy, but scientists found fission easier to control

To tap into nuclear's potential, NASA launched a research program called SNAP.

This kickstarted the development of radioisotope thermoelectric generators, which use plutonium-238

and thermocouples to convert heat into electricity.

These units have been on a number of famous missions like Curiosity, Cassini, Pioneer,

and even Voyager 1, which is currently cruising on RTG power 21 billion kilometers away from

The program also developed SNAP 10A, a fission reactor that's considered the U.S.'s first

It took off in 1965, failed after 43 days into the mission, and will be orbiting Earth

All subsequent nuclear space programs, like NERVA, which looked into nuclear powered rockets,

were shuttered or just didn't get off the ground.

Now, given, they were working on bigger power systems, which was part of the problem, I

But, they were also chasing materials and processes and things that weren't available

Today, nuclear power systems are seeing a comeback, and that's thanks to new mission

When we start talking about putting men on the moon in 2024 or on Mars in the 2030's,

Kilopower, is one to ten kilowatts of electrical power.

We have sodium heat pipes that are attached to that core.

That sodium heat pipe carries that heated vapor up to the Stirling power conversion

system, and then we have to cool the cold side of the engines to get that temperature

difference that we need for that power conversion and keep the engines from overheating.

The other pieces of the reactor that are, obviously, very important are the neutron

That helps direct those neutrons back into the core and keep that chain reaction going

Before operating this, we have a poison rod inside the center of that core and then, when

we get to our destination we have a mechanism that would pull that rod out, make sure that

those neutrons will not be absorbed anymore and they can start the actual chain reaction

One of the biggest attributes, I think, to the success of this program was that we kept

And, we're looking to make it as lightweight as possible.

Once the design was approved by NASA, the system and the people behind it were shipped

KRUSTY was the experiment, which stood for Kilopower reactor using Stirling technology.

That experiment was really a follow-on to the Duff experiment, a demonstration using

Los Alamos, typically, or always likes to name their nuclear experiments after Simpsons'

We run through all those mission scenarios, where we would turn off the cooling to the

whole top end of the power conversion system and see how the reactor reacted.

And then, how we could really mess with them and see is it going to be a stable controlled

The experiment culminated in a 28-hour test, from reactor startup to shutdown.

It operated at 800 degrees Celsius and produced over 4 kilowatts of power.

The highest power nuclear mission we've ever completed was Cassini, that had 870 watts.

So, already our lowest is already higher than any mission that's ever been done.

We did things to that reactor that you shouldn't do to a reactor, but it was really neat the

From concept to test was about three and a half years.

Me and one of my buddies down at Marshall, as we were cleaning things up afterwards.

You know, the thousands of CAD models that we had and the information that was generated,

We worked a lot of hours and just had a lot of passion.

The fact that it worked really well was just a bonus.

This was a major step in demonstrating nuclear power's feasibility in the new space age,

The real challenges are really political and how we develop all the safety and security

There's a whole lot of work related to making sure that there's no way you accidentally

And then there's what we call the launch safety piece, which also has a criticality accident

Subtitles ListPlay Video

NASA's New Space Reactor Is Powered by Nuclear Fission

demonstrate

destination

experiment

develop