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NASA Successfully Tests Revolutionary Rocket That Could Get Us to Mars Faster (www.sciencealert.com)

submitted 10 months ago by [email protected] to c/[email protected]

40 comments fedilink hide all child comments

After setting foot on the Moon, the next destination for humankind is Mars, which presents a whole new set of challenges in speedy, long-distance space travel.

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[–] [email protected] 170 points 10 months ago (5 children)

It's a Rotating Detonation Rocket Engine"

What makes the RDRE so revolutionary is that it makes use of a sustained detonation circling around a ring-shaped channel, fed by a mix of fuel and oxygen which is ignited by each passing explosion.
Crucially, the RDRE uses less propellant fuel than conventional rocket engines, and is simpler in terms of its machinery and mechanisms. That means going into space becomes cheaper, and traveling further distances becomes possible.

Saved you a click.

[–] [email protected] 38 points 10 months ago* (last edited 10 months ago) (1 children)

NASA invented a space ship powered by a rotary engine? Noice, at least until the apex seals give out, but they should be good for 80k at least.

[–] [email protected] 24 points 10 months ago (1 children)

Wankel and Mazda shine blessings upon you and your RX family

[–] [email protected] 2 points 10 months ago

The wankel and rdre aren't really related, but they're similar in that they're both oddball engines with surprising performance.

Of all of my near future rocket engine predictions, a working aerospike rdre was not on my list... I'm honestly very impressed!

[–] [email protected] 23 points 10 months ago

Thank you I was running low on clicks.

[–] [email protected] 16 points 10 months ago (2 children)

That sounds sick. I wonder which sci-fi author came up with this idea ~60 years ago.

[–] [email protected] 4 points 10 months ago (1 children)

My bet's on Heinlein.

[–] [email protected] 1 points 10 months ago

I'd put money on Robert Forward.

[–] [email protected] 1 points 10 months ago

Maybe the Jetsons, or the turbine engines in Star Wars? If you squint hard enough, it comes close enough.

[–] [email protected] 12 points 10 months ago

So it’s truthfully Revolutionary, hark! A spinning engine

[–] [email protected] 11 points 10 months ago (1 children)

So they invented the rocket powered wheel?

[+] [email protected] -13 points 10 months ago (1 children)

No, it’s just gas powered car that still needs tanks and has everyone knows a around trip back to anywhere requires gas. The “ECO” of space travel.

[–] [email protected] 14 points 10 months ago (1 children)

And how else are you going to move things in space? Are you hiding a reactionless drive over there? Less fuel use is a good thing.

[–] [email protected] -5 points 10 months ago (1 children)

We don’t have unlimited fuel, rockets cost too much fuel. It’s not even normal fuel either, it’s rare chemistry rocket technology that takes a while to develop.

[–] [email protected] 5 points 10 months ago

Alright so nobody's going to stop launching rockets realistically, there's too much potential in space to just ignore, rdre are a way to do the same with less.

[–] [email protected] 28 points 10 months ago

Revolutionary

I see what they did there.

[–] [email protected] 24 points 10 months ago* (last edited 10 months ago) (2 children)

This is a fancy aerospike engine right? The rotating detinations gives it higher chamber pressure and therefore better ISP or something?

I will look for the Scott Manley video on this later (I think it was him?) Edit: also a Real Engineering one that explains the aero-spike nozzle

Anyone have the ISP of this experiment to compare to other engines?

[–] [email protected] 6 points 10 months ago (2 children)

Should be the rotating detonation engine.

[–] [email protected] 3 points 10 months ago

Video is here (3 years old)

[–] [email protected] 3 points 10 months ago

Real engineering also did one (actually better than Scott's I think)

[–] [email protected] 6 points 10 months ago

You know what gets even better ISP? NERVA

[–] [email protected] 4 points 10 months ago

I remember first hearing about the development of this back in the early 90s on Beyond 2000.

[–] [email protected] 3 points 10 months ago (2 children)

I heard that the destination is actually Venus because it's closer and has oxygen in the upper atmosphere.

[–] [email protected] 9 points 10 months ago* (last edited 10 months ago) (2 children)

Venus is significantly more hostile than Mars, so while we definitely want to do more with Venus, Luna and Mars are clear next-ups for manned landings.

While all of Mars is hostile to human life, Venus is also incredibly hostile to equipment, and thus requires a different approach to even unmanned launches.

Current maximum lifetime for any unmanned craft in the Venusian atmosphere (to say nothing of the ground) is only about 2 hours.

[–] [email protected] 5 points 10 months ago

Venus is interesting. While the surface is extremely hostile, the upper atmosphere is maybe the most similar to Earth-like environment out there in the solar system. At about 50km up in the air, the air pressure is about 1 Earth atmosphere, and the ambient temperature is about 20C. A 80/20% nitrogen-oxygen gas mixture is buoyant too at that depth, so a balloon filled with breathable air will just float. A rupture won't cause explosive decompression like it would on Mars either. In addition, the gravity one would experience is only very slightly less than that of Earth, and the large atmosphere also provides some shielding against radiation.

Mars doesn't have these perks. Mars is cold, really cold, with only 1/3rd of the gravity of Earth, has practically no radiation shielding, and any breach would cause explosive decompression and almost instant unconsciousness. On top of that, regular solar panels really don't work that well on Mars because of the extra distance from the Sun, while solar panels would actually work better in the upper atmosphere of Venus.

[–] [email protected] 4 points 10 months ago (1 children)

Isn't that on the surface? I believe Venus's upper atmosphere is a lot more welcoming.

[–] [email protected] 2 points 10 months ago (1 children)

That's true about their upper atmosphere, but we're nowhere close to being able to capitalize on it (as in, no missions even planned). Closest we've got on paper is an orbiter by the early 30s.

Hopefully in my lifetime we see an upper atmosphere balloon or something. That alone would be unbelievably cool.

[–] [email protected] 2 points 10 months ago (1 children)

give me a hot air balloon and a hang glider and send me out Ill be the pioneer

[–] [email protected] 2 points 10 months ago* (last edited 10 months ago)

Dude what's neat about this is Oxygen on Venus is like Helium on Earth (less dense than most of the atmosphere, so rises naturally) so your balloon doesn't even need to be hot, just really sturdy.

[–] [email protected] 3 points 10 months ago

Theres oxygen on Venus like there's argon on earth, it's so miniscule it's useless.

[–] [email protected] 0 points 10 months ago (2 children)

Correction: Get the rich fast to mars.

[–] iammike 4 points 10 months ago

If they're leaving them there, I'd be all for it

[–] [email protected] 0 points 10 months ago

NASA plans to have a manned mission to Mars in the next 6 years.

[+] [email protected] -6 points 10 months ago (1 children)

[deleted]

[–] [email protected] 7 points 10 months ago (1 children)

2km is a measure of distance not speed...

[+] [email protected] 0 points 10 months ago (1 children)

[deleted]

[–] [email protected] 6 points 10 months ago (1 children)

The international standard is km/h.

[–] [email protected] 2 points 10 months ago (1 children)

Why not using SI units and m/s?

[–] [email protected] 3 points 10 months ago (1 children)

km/h is an SI unit.

[–] [email protected] 2 points 10 months ago* (last edited 10 months ago) (1 children)

I'm sorry to be a stickler, but it's not an SI unit.
Have a look at p. 145 and "Non-SI units that are accepted for use with the SI", if you want to know more: https://www.bipm.org/documents/20126/41483022/SI-Brochure-9.pdf/fcf090b2-04e6-88cc-1149-c3e029ad8232?version=1.22

[–] [email protected] 2 points 10 months ago (1 children)

Hey, no need to be sorry. I appreciate the search for correctness and especially the reference document.

Here's what I've found.

There is no mention of km/h in section 4, "Non-SI units that are accepted for use with the SI". It does mention h, making it a "non-SI unit that's accepted for use with the SI."

km/h is its own unit separate from h. It's a unit of speed, derived from km and h.

My gut feel at this point is that km/h could be an SI unit since it's a unit of speed derived from an SI unit for distance and a non-SI unit accepted for use with the SI for time.

Furthermore, searching the document for mentions of km/h, there's this bit on page 127, section 2.1, "Defining the unit of a quantity":

For a particular quantity different units may be used. For example, the value of the speed v of a particle may be expressed as v = 25 m/s or v = 90 km/h, where metre per second and kilometre per hour are alternative units for the same value of the quantity speed.

This paragraph suggests (even though it doesn't outright say it) that km/h is indeed an SI unit.

I haven't found anything clearly saying whether km/h is an SI unit or not. Not on that document, not by searching the web. The research above makes me lean towards the idea that it is one.

If you found otherwise, I'd love to compare notes and learn further.

[–] [email protected] 1 points 10 months ago

I see it quite simplistic: if it isn't listed as SI unit by the BIPM it isn't one.
Lending a helping hand on how to deal with derived units (e.g. km/h) doesn't mean those derived units are endorsed as SI units.
But that's just my point of view.