New nuclear engine concept could help realize 3-month trips to Mars

Seattle-based Ultra Safe Nuclear Technologies (USNC-Tech) has developed a concept for a new Nuclear Thermal Propulsion (NTP) engine and delivered it to NASA. Claimed to be safer and more reliable than previous NTP designs and with far greater efficiency than a chemical rocket, the concept could help realize the goal of using nuclear propulsion to revolutionize deep space travel, reducing Earth-Mars travel time to just three months.

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Tau.Neutrino said:

New nuclear engine concept could help realize 3-month trips to Mars

Seattle-based Ultra Safe Nuclear Technologies (USNC-Tech) has developed a concept for a new Nuclear Thermal Propulsion (NTP) engine and delivered it to NASA. Claimed to be safer and more reliable than previous NTP designs and with far greater efficiency than a chemical rocket, the concept could help realize the goal of using nuclear propulsion to revolutionize deep space travel, reducing Earth-Mars travel time to just three months.

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Meh, probably better just to use it to deliver bigger payloads in the same time period.

Tau.Neutrino said:

New nuclear engine concept could help realize 3-month trips to Mars

Seattle-based Ultra Safe Nuclear Technologies (USNC-Tech) has developed a concept for a new Nuclear Thermal Propulsion (NTP) engine and delivered it to NASA. Claimed to be safer and more reliable than previous NTP designs and with far greater efficiency than a chemical rocket, the concept could help realize the goal of using nuclear propulsion to revolutionize deep space travel, reducing Earth-Mars travel time to just three months.

more…

> the new concept engine is more reliable than previous NTP designs and can produce twice the specific impulse of a chemical rocket.

Going for safe here, not powerful.

> Ceramic Micro-encapsulated fuel to power the engine’s reactor. This fuel is enriched to between 5 and 20 percent. The fuel is then encapsulated into particles coated with zirconium carbide (ZrC).

5 to 20 percent. Let me compare that. They’re not lying, that’s exactly what wikipedia says. In more detail:

“Low enriched uranium (LEU) has a lower than 20% concentration of 235U. In commercial power reactors, uranium is enriched to 3 to 5% 235U. High-assay LEU is enriched from 5–20%. eg. LEU used in research reactors is usually enriched 12 to 19.75% 235U. Highly enriched uranium (HEU) has a 20% or higher concentration of 235U.”

Zirconium carbide makes perfect sense. Low neutron absorption cross section, minimal damage to crystal structure, slight moderating effect from the carbon.

> more rugged than conventional nuclear fuels and can operate at high temperatures.

Agree. More expensive, too, but for space travel the cost of the fuel cladding is not the dominant cost.

The dominant other use for high temperature nuclear reactors is in nuclear submarines. It may end up there first.

I’d like to see more on how they plan to get from a nuclear reactor to a rocket nozzle.

Ba!
Just use the old Project Orion, take a hundred times as much gear and make the trip in less than a month.

Spiny Norman said:

Ba!
Just use the old Project Orion, take a hundred times as much gear and make the trip in less than a month.

Yes. I have different levels of “impossible”. From most impossible to least we have:
Physically impossible – eg. people travelling faster than light
Technologically impossible – eg. people travelling 90% of the speed of light
Financially impossible – eg. people travelling 0.1% of the speed of light (300 km/s)
Politically impossible – eg. Project Orion
Inefficient – eg. Earth to Mars in less than 8.5 months (Hohmann transfer orbit)

I don’t see what’s wrong with 8.5 months – that’s no different to how long it used to take a sailing ship to circumnavigate the world.

There’s no financial, technological or physical hindrance to the old Project Orion. Only a political hindrance.

mollwollfumble said:

Spiny Norman said:

Ba!
Just use the old Project Orion, take a hundred times as much gear and make the trip in less than a month.

Yes. I have different levels of “impossible”. From most impossible to least we have:
Physically impossible – eg. people travelling faster than light
Technologically impossible – eg. people travelling 90% of the speed of light
Financially impossible – eg. people travelling 0.1% of the speed of light (300 km/s)
Politically impossible – eg. Project Orion
Inefficient – eg. Earth to Mars in less than 8.5 months (Hohmann transfer orbit)

I don’t see what’s wrong with 8.5 months – that’s no different to how long it used to take a sailing ship to circumnavigate the world.

There’s no financial, technological or physical hindrance to the old Project Orion. Only a political hindrance.

So We’ll Realise Orion At Around The Same Time We Arrest Global Warming

SCIENCE said:

mollwollfumble said:

Spiny Norman said:

Ba!
Just use the old Project Orion, take a hundred times as much gear and make the trip in less than a month.

Yes. I have different levels of “impossible”. From most impossible to least we have:
Physically impossible – eg. people travelling faster than light
Technologically impossible – eg. people travelling 90% of the speed of light
Financially impossible – eg. people travelling 0.1% of the speed of light (300 km/s)
Politically impossible – eg. Project Orion
Inefficient – eg. Earth to Mars in less than 8.5 months (Hohmann transfer orbit)

I don’t see what’s wrong with 8.5 months – that’s no different to how long it used to take a sailing ship to circumnavigate the world.

There’s no financial, technological or physical hindrance to the old Project Orion. Only a political hindrance.

So We’ll Realise Orion At Around The Same Time We Arrest Global Warming

> So We’ll Realise Orion At Around The Same Time We (Stop Worrying About) Global Warming

More seriously, we’ll realise Orion sometime after we run out of oil.
Nuclear explosions at depth are a great way to stimulate the production of oil.

Only after civilian nuclear explosions underground have become common practice will governments open up enough to allow nuclear explosions in space.

mollwollfumble said:

I don’t see what’s wrong with 8.5 months – that’s no different to how long it used to take a sailing ship to circumnavigate the world.

Sure, but there’s the much longer transit time in both directions, which requires better shielding against cosmic radiation, a lot more consumables, far less equipment, and the inability to leave any time you like and not have to wait for the return window.

Spiny Norman said:

mollwollfumble said:

I don’t see what’s wrong with 8.5 months – that’s no different to how long it used to take a sailing ship to circumnavigate the world.

Sure, but there’s the much longer transit time in both directions, which requires better shielding against cosmic radiation, a lot more consumables, far less equipment, and the inability to leave any time you like and not have to wait for the return window.

I imagine they had no choice for the time frame back then but would have loved to do it a week or two instead
Shorter time frame means colonisation is a lot more feasible

Spiny Norman said:

mollwollfumble said:

I don’t see what’s wrong with 8.5 months – that’s no different to how long it used to take a sailing ship to circumnavigate the world.

Sure, but there’s the much longer transit time in both directions, which requires better shielding against cosmic radiation, a lot more consumables, far less equipment, and the inability to leave any time you like and not have to wait for the return window.

The shielding isn’t a great issue, because it’s linear with time.

Consumables, though, you have a real point there. Power requirements at take-off increase almost exponentially with the number of consumables required.

Cymek said:

Spiny Norman said:

mollwollfumble said:

I don’t see what’s wrong with 8.5 months – that’s no different to how long it used to take a sailing ship to circumnavigate the world.

Sure, but there’s the much longer transit time in both directions, which requires better shielding against cosmic radiation, a lot more consumables, far less equipment, and the inability to leave any time you like and not have to wait for the return window.

I imagine they had no choice for the time frame back then but would have loved to do it a week or two instead
Shorter time frame means colonisation is a lot more feasible

No more so than colonisation of Australia.

mollwollfumble said:

Spiny Norman said:

mollwollfumble said:

I don’t see what’s wrong with 8.5 months – that’s no different to how long it used to take a sailing ship to circumnavigate the world.

Sure, but there’s the much longer transit time in both directions, which requires better shielding against cosmic radiation, a lot more consumables, far less equipment, and the inability to leave any time you like and not have to wait for the return window.

The shielding isn’t a great issue, because it’s linear with time.

Consumables, though, you have a real point there. Power requirements at take-off increase almost exponentially with the number of consumables required.

Let’s look at consumables. Say for food 1.5 kg per person per day. Then 8.5 months is 435 kg of food per person, one way.

That’s still not _too_bad. But you’re right, cutting that in half would help a lot.

I wonder how effective cannibalism would be on the return journey?

mollwollfumble said:

I wonder how effective cannibalism would be on the return journey?

You’re an ideas man.

mollwollfumble said:

mollwollfumble said:

Spiny Norman said:

Sure, but there’s the much longer transit time in both directions, which requires better shielding against cosmic radiation, a lot more consumables, far less equipment, and the inability to leave any time you like and not have to wait for the return window.

The shielding isn’t a great issue, because it’s linear with time.

Consumables, though, you have a real point there. Power requirements at take-off increase almost exponentially with the number of consumables required.

Let’s look at consumables. Say for food 1.5 kg per person per day. Then 8.5 months is 435 kg of food per person, one way.

That’s still not _too_bad. But you’re right, cutting that in half would help a lot.

I wonder how effective cannibalism would be on the return journey?

Could you send unmanned supply ships that could be docked with mid journey for resupply, our would fuel logistics be a problem

Cymek said:

mollwollfumble said:

mollwollfumble said:

The shielding isn’t a great issue, because it’s linear with time.

Consumables, though, you have a real point there. Power requirements at take-off increase almost exponentially with the number of consumables required.

Let’s look at consumables. Say for food 1.5 kg per person per day. Then 8.5 months is 435 kg of food per person, one way.

That’s still not _too_bad. But you’re right, cutting that in half would help a lot.

I wonder how effective cannibalism would be on the return journey?

Could you send unmanned supply ships that could be docked with mid journey for resupply, our would fuel logistics be a problem

Unmanned resupply makes a lot of sense.

mollwollfumble said:

Cymek said:

mollwollfumble said:

Let’s look at consumables. Say for food 1.5 kg per person per day. Then 8.5 months is 435 kg of food per person, one way.

That’s still not _too_bad. But you’re right, cutting that in half would help a lot.

I wonder how effective cannibalism would be on the return journey?

Could you send unmanned supply ships that could be docked with mid journey for resupply, our would fuel logistics be a problem

Unmanned resupply makes a lot of sense.

So you send them ahead at a slower pace and them catch up with them on the journey and slow down and dock

Cymek said:

mollwollfumble said:

Cymek said:

Could you send unmanned supply ships that could be docked with mid journey for resupply, our would fuel logistics be a problem

Unmanned resupply makes a lot of sense.

So you send them ahead at a slower pace and them catch up with them on the journey and slow down and dock

Wouldn’t it be better to time their departure so that each one would be traveling at your speed when you got there.

Tamb said:

Cymek said:

mollwollfumble said:

Unmanned resupply makes a lot of sense.

So you send them ahead at a slower pace and them catch up with them on the journey and slow down and dock

Wouldn’t it be better to time their departure so that each one would be traveling at your speed when you got there.

That would work as well

mollwollfumble said:

Let’s look at consumables. Say for food 1.5 kg per person per day. Then 8.5 months is 435 kg of food per person, one way.

That’s still not _too_bad. But you’re right, cutting that in half would help a lot.

Not in half, better than one eighth and the ability to carry quite a lot more food with no effective penalty if you wanted. Don’t forget that the Orion that had most of the design work done on it allowed for a 700 kg barbers chair.
Because they could.