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Airbus to build 'first interplanetary cargo ship'

bbc.com

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Re: Airbus to build 'first interplanetary cargo ship'

#151

Post by hoorayimhelping »

sandworm101 wrote: post #54
lt_kernelpanic wrote: post #10

Question for the experts: what are the tests and analysis that we cannot do via a rover-based lab and hence need to send the samples to Earth? Asking out of curiosity (pun not intended!).

Better question: What will we learn that we cannot learn from all the Martian rocks we already have on earth . There have been plenty or Martian meteors found in Antarctica, and no doubt many more if we redoubled our efforts to find them. Many once claimed to have found evidence of life in these rocks already. Some of us are even old enough to remember President Clinton's speech on the subject. (That isn't a deepfake…

There is a big, big difference between, "we found a rock on earth that is probably from Mars that was blasted here some time in the past," and, "we went to a specific area of Mars and got a rock and brought it back." Not least of which is the intrinsic value and aspirational nature of us actually fetching things from other planets ourselves, with intent and purpose, rather than luckily stumbling upon some.

Re: Airbus to build 'first interplanetary cargo ship'

#152

Post by TomMarius »

growlist wrote: post #85
ever1 wrote: post #69

Earlier quoted context omitted.

What are you talking about ? So far Ariane program seems to be a commercial success. ESA on a scientific point of view too. It is true that Ariane 6 will not be reusable, although cheaper than Ariane 5, just like ALL reliable commercial launchers today (even tomorrow for ULA) outside of space X. It is clear that this is the future. However, these are only the first steps. I am not sure that today space X will be able…

ESA's leaders have mocked and disparaged SpaceX's approach in recent years; why would they bother unless they considered SpaceX a serious threat? They must be worried. I'll also point out that SpaceX naysayers have a dismally poor record of predicting the future. This isn't an EU/US thing and I totally agree with you on ULA, SLS and I might add Roscosmos etc. I wish ALL launch providers would move towards reusability…

I don't agree nor disagree with you, but I hate the idea that criticism means the critic is afraid.

Re: Airbus to build 'first interplanetary cargo ship'

#153

Post by hoorayimhelping »

lt_kernelpanic wrote: post #10

Question for the experts: what are the tests and analysis that we cannot do via a rover-based lab and hence need to send the samples to Earth? Asking out of curiosity (pun not intended!).

Looking at a rock with our own eyes, and feeling it with our own senses can provide context and meaning that a robot might have trouble conveying.

Re: Airbus to build 'first interplanetary cargo ship'

#155

Post by antonvs »

bufferoverflow wrote: post #41

> The joint American-European project is expected to cost billions and take just over a decade to implement. I'm 99% sure that if SpaceX's starship takes off, it will fly to Mars and back within a few years. But still, competition is good.

> I'm 99% sure that if SpaceX's starship takes off, it will fly to Mars and back within a few years.

I'm 99% sure that's wrong.

Re: Airbus to build 'first interplanetary cargo ship'

#156

Post by capableweb »

Someone wrote: post #139
ape4 wrote: post #52

The article mentions a "football sized package". Hope there is no confusion between American and European football.

Reading https://www.esa.int/Science_Exploration/Human_and_Robotic_Ex... , they mean “basketball size”. It seems the BBC thinks their readers do not know how large those are.

Or maybe BBC thinks it's readers are more familiar with the size of a football (as in soccer, of course) than the size of a basketball (although they are the same, but someone who doesn't know the size of a basketball wouldn't, of course)

Re: Airbus to build 'first interplanetary cargo ship'

#157

Post by mLuby »

raldi wrote: post #89
rsynnott wrote: post #75

Earlier quoted context omitted.

Is that something returning from Mars _orbit_, or returning samples from the surface?

Exactly. Returning from orbit is "easy", you just go into a free-return trajectory and don't even do much of a burn at Mars, if any at all. Getting a sample from the surface basically means you need to do a deceleration burn to get into orbit, and then the reverse after grabbing the sample (which itself must be accelerated to orbital speed). No small thing.

A free-return trajectory doesn't enter orbit around a body, indeed its appeal is that if your propulsion fails while on such a course, you'll coast home "for free" rather than enter orbit around your target or drift into deep space.

Entering orbit almost always requires an orbital insertion burn, and in the case of an Earth-Mars Hohmann transfer definitely does.

Your point stands though: returning from a fly-by (including a free-return) requires much less fuel than returning from orbit, and even that's much easier than returning from the surface.

For fun, take a look at rotovators (AKA "momentum exchange tethers") that could make orbital capture/departure—and even landing/launch—"free" on bodies with minimal atmosphere.

Re: Airbus to build 'first interplanetary cargo ship'

#158

Post by freeopinion »

mabbo wrote: post #26
lt_kernelpanic wrote: post #10

Question for the experts: what are the tests and analysis that we cannot do via a rover-based lab and hence need to send the samples to Earth? Asking out of curiosity (pun not intended!).

Simple answer from a space nerd: Rovers are small, light, and have very little energy. So what we can't do is anything that requires a large or heavy device or anything that requires significant energy. They break/fail. They take forever to make happen. Want to burn 20kg of soil to see if there's any trace of specific elements? You'll need a furnace. Those are both heavy and high-energy. You could do a smaller scale…

> Anything that requires significant energy

So instead of sending a rover with 4x or 10x energy, the answer is a mission that requires enough energy to launch the samples all the way back to Earth? This makes me smile.

I do agree though. We can expend 1000x the energy of the return trip once the samples are back on earth. And we also have the luxury of unlimited time to invent new tests and new tech to apply to whatever is left of the samples.

Re: Airbus to build 'first interplanetary cargo ship'

#159

Post by _Microft »

hinkley wrote: post #133
_Microft wrote: post #39

Earlier quoted context omitted.

New Glenn is not that different from Falcon 9 regarding reusability as they will have to expend the upper stage and fairings every single launch.

Didn’t they just recover both fairings on the last launch? I don’t know how you want to work the math, but it is probably best to think of it in a fractional way. Between accidents and wear do they manage better than 4 launches in average? They just managed 6 for one lower stage, with tighter turnaround time. We don’t know how much of that rocket was reused. So we might be talking about expending 20% of a lower stage…

Yes, they did. Great achievement, I was afraid they might abandon the approach sooner or later.

This only meant to say that New Glenn isn't that different from Falcon 9. Both are limited (with respect to cost and frequency of launches) in that they need to throw away hardware on every launch. Starship on the other hand will be a true game changer if it works as intended.

Re: Airbus to build 'first interplanetary cargo ship'

#160

Post by klyrs »

pansa2 wrote: post #3

> "This is not just twice as difficult as any typical Mars mission; it's twice squared" So, four times as difficult?

Squared twice?

  x -> x^2^2 = x^4
Doubled and squared?

  x -> (2x)^2 = 4x^2
Difficulty factor of 2 is squared?

  x -> (2^2)x = 4x
Or was that squared twice?

  x -> (2^2^2)x = 16x
All of these functions agree at x = 0, so can we conclude that it's gonna be way easy??

Lesson: don't handwave your math when you're talking to lay journalists, because nerds are gonna read it and be horrified.

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