this post was submitted on 04 Jan 2024

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309

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

submitted 1 year ago by Hypx@kbin.social to c/technology@lemmy.world

42 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.

all 44 comments

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[–] anonionfinelyminced@kbin.social 169 points 1 year 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.

[–] ramjambamalam@lemmy.ca 38 points 1 year ago* (last edited 1 year 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.

[–] RangerAndTheCat@lemmy.world 24 points 1 year ago (1 children)

Wankel and Mazda shine blessings upon you and your RX family

[–] Cocodapuf@lemmy.world 2 points 1 year 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!

[–] Agent641@lemmy.world 23 points 1 year ago

Thank you I was running low on clicks.

[–] prole@sh.itjust.works 16 points 1 year ago (2 children)

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

[–] c0mbatbag3l@lemmy.world 4 points 1 year ago (1 children)

My bet's on Heinlein.

[–] ikidd@lemmy.world 1 points 1 year ago

I'd put money on Robert Forward.

[–] T156@lemmy.world 1 points 1 year ago

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

[–] Donebrach@lemmy.world 12 points 1 year ago

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

[–] LazaroFilm@lemmy.world 11 points 1 year ago (1 children)

So they invented the rocket powered wheel?

[–] Morphit@feddit.uk 27 points 1 year ago

Revolutionary

I see what they did there.

[–] Nighed@sffa.community 23 points 1 year ago* (last edited 1 year 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?

[–] SkybreakerEngineer@lemmy.world 6 points 1 year ago

You know what gets even better ISP? NERVA

[–] Ghyste@sh.itjust.works 6 points 1 year ago (2 children)

Should be the rotating detonation engine.

[–] Nighed@sffa.community 3 points 1 year ago (1 children)

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

[–] PipedLinkBot@feddit.rocks 1 points 1 year ago

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[–] Nighed@sffa.community 3 points 1 year ago (1 children)

Video is here (3 years old)

[–] PipedLinkBot@feddit.rocks 1 points 1 year ago

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[–] Ejh3k@lemmy.world 4 points 1 year ago

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

[–] Desistance@lemmy.world 3 points 1 year ago (2 children)

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

[–] SCB@lemmy.world 9 points 1 year ago* (last edited 1 year 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.

[–] sndrtj@feddit.nl 5 points 1 year 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.

[–] danielbln@lemmy.world 4 points 1 year ago (1 children)

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

[–] SCB@lemmy.world 2 points 1 year 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.

[–] TIMMAY@lemmy.world 2 points 1 year ago (1 children)

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

[–] SCB@lemmy.world 2 points 1 year ago* (last edited 1 year 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.

[–] c0mbatbag3l@lemmy.world 3 points 1 year ago

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

[–] BlackSkinnedJew@lemmynsfw.com 0 points 1 year ago (2 children)

Correction: Get the rich fast to mars.

[–] iammike@programming.dev 4 points 1 year ago

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

[–] SCB@lemmy.world 0 points 1 year ago

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

[+] Shady_Shiroe@lemmy.world -6 points 1 year ago (1 children)

[deleted]

[–] SonarTaxLaw@lemmy.world 7 points 1 year ago (1 children)

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

[+] Shady_Shiroe@lemmy.world 0 points 1 year ago (1 children)

[deleted]

[–] c10l@lemmy.world 6 points 1 year ago (1 children)

The international standard is km/h.

[–] zergtoshi@lemmy.world 2 points 1 year ago (1 children)

Why not using SI units and m/s?

[–] c10l@lemmy.world 3 points 1 year ago (1 children)

km/h is an SI unit.

[–] zergtoshi@lemmy.world 2 points 1 year ago* (last edited 1 year 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

[–] c10l@lemmy.world 2 points 1 year 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.

[–] zergtoshi@lemmy.world 1 points 11 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.