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I just don’t get it
Well, if you take it that this planet is ****ed. Then it's just a matter of the rich looking to bail out of a sinking ship, or at the very least monetise the eventual bail-out. Or, stay here and sort it, but not whilst there's loads of poor people everywhere nausing up the aesthetics. Send them all to Mars! And still charge them rent cos, well, you colonised it. Win/win.
Why not concentrate on fixing up earth.
...because constant economic growth isn't possible in a closed system with finite resources.
Well, if you take it that this planet is ****. Then it’s just a matter of the rich looking to bail out of a sinking ship, or at the very least monetise the eventual bail-out. Or, stay here and sort it, but not whilst there’s loads of poor people everywhere nausing up the aesthetics. Send them all to Mars! And still charge them rent cos, well, you colonised it. Win/win.
But my point is no matter how shit it gets on earth everywhere else will be worse because they are completely uninhabitable. Using your metaphor, there is nowhere to bail out too. You would live the rest of your life in the lifeboat anchored to a barren rock Island
It will always (in any reasonably foreseeable future) be better on earth. If you are rich enough you will be insulated from the impact of climate change. Whereas what would be the point of being a billionaire in some sort of subsistence existence trapped in a small biosphere
because constant economic growth isn’t possible in a closed system with finite resources.
Different thread but, just change the model then. Constant economic growth is not a necessity
On this specific venture, I don’t know. But the scientific advances born from Mercury / Gemini / Apollo are very well documented.
I’m aware of the historic stuff but asking about the here and now. I don’t think there is anything going on that outweighs the damage being done. We have no viable way of dealing with carbon emissions. Adding to them in unnecessary ways is just a dick move.
Whereas what would be the point of being a billionaire in some sort of subsistence existence trapped in a small biosphere
Good point. Depends on how much coke and hookers you had with you. Probably a lot if you were a billionaire. Would also need an awesome stereo. Again, not a problem if you're a billionaire. No neighbours too to complain. Sounds alright to be honest...
.... just change the model then. Constant economic growth is not a necessity
Yeah, I know, that was my point. Shame we're not in charge, eh?
Sorry andeh, missed that and wholeheartedly agree. We’re a bit ****ed in the not too distant future aren’t we.
We need to increase our presence on other planets in the solar system to ensure humanity’s survival. Having all your eggs in one basket is a bad survival strategy.
WTAF...
Sorry andeh, missed that and wholeheartedly agree. We’re a bit **** in the not too distant future aren’t we.
As you say a whole 'nother thread but yes - we need to go to zero growth. In fact negative growth to reach a sustainable lifestyle for humans on this planet. without that the environmental collapse will happen in our ( or your childrens lifetimes). the harbingers of the collapse are already here
We have plenty of "stuff" for everyone on the planet if its shared out a bit better. We don't need more "stuff"
...We’re a bit **** in the not too distant future aren’t we.
Yeah, without a doubt. Thinking about having a kid, and this is genuinely a major factor in my decision making.
I've been doing some energy modelling on buildings lately for uni, using predicted weather files for 2050 and 2080. It's not looking good, lads.
...anyway, Mars!
andeh - as above - the environmental collapse is happening in your childrens lifetimes
we’re just not technically advanced enough to do much outside of our planet, i doubt we ever will be
200 years ago we were travelling round in horses and carts and marrying people from the next village. We're now seriously discussing the potential to colonise the moon and planets.
Absolutely I recognise the balls up we've made of it, and the implications that need fixing asap. But given the demonstrated capability to progress, it's not a matter of if, just when.
I'm not convinced its "when" Too many huge issues to be solved. The amount of stuff that would need to be boosted into orbit is a huge amount more than humans have ever done and the logistics of the many months of travel are huge.
robot exploration yes but humans? I doubt it
we’re just not technically advanced enough to do much outside of our planet, i doubt we ever will be
That's the whole point of programmes like these.
But some of the issues are virtually unsolvable - like getting the amount of stuff needed for a human expedition to Mars into orbit - the amount of energy needed is huge. Hundreds of times the moon landings plus the issues of the actual travel to Mars, the fuel needed for that, the sheilding needed to protect the people, the physiological damage to the people from being under microgravity that long.
I'd love to see it but the scale of the problems I think is simply too big without a whole new source of energy so we could get mass into orbit easier and also use a powered flight to Mars not a cometary orbit
You're not necessarily wrong. Personally I'm on the fence about all this. It's a great way of getting governments to stimulate the high tech economy, or to get billionaires to do it themselves, but on the other hand you could still do that and end up with something more worthy.
I think the aim is to try and work out how to make stuff on the moon or get it from asteroids. All you need is solar panels and water, which is around here and there in the solar system.
It would be interesting to work out how much fuel is required to get a spaceship back off Mars and back to earth. It would be a lot smaller than the rocket needed to get the same craft up into orbit from Earth. I'm not sure how many dead drops of fuel onto a Mars site it would need, but perhaps not that many. If no-one else works it out I'll have a stab later 🙂
Having a viable re-usable rocket to take stuff into Earth orbit cheaply would be a massive help.
We’re now seriously discussing the potential to colonise the moon and planets.
No, we're really not. Do you have any idea what the narrow margins are for human life on earth ( and any other planet)?
Alas I only tuned into what the lecturer was saying very late on, but just the percentage Oxygen range alone was a complete eye opener.
Any idea that we will colonise other planets is just bollocks.
It would be interesting to work out how much fuel is required to get a spaceship back off Mars and back to earth. It would be a lot smaller than the rocket needed to get the same craft up into orbit from Earth.
Depends if its a cometary orbit or a powered orbit - cometary is a lot slower but a lot less fuel but yes the biggest fuel use is getting out of earth orbit
don't forget the parasitic weight thing either - to get a tonne of fuel into orbit you need hundreds of tonnes of fuel burnt to get it there
The slower cometary route means many tonnes of food are needed for the people plus oxygen and water. Powered orbit needs many tonnes of fuel
You hit the law of diminishing returns very quickly so rather than a few big launches you will need hundreds of launches into orbit using the rockets we have now.
then there is still the physiological effects on the people.
It’s far harder to fix Earth’s problems than send a few people to Mars.
As an engineer and scientist who’s involved with these efforts, I can’t begin to tell you how wrong you are. Almost no problems are as constrained as those involving flight with humans aboard. It’s almost absurdly difficult and yet it’s made to look routine.
no they aren’t. CO2 is a huge issue and pissing about with space rockets causes a lot of it. It’s adding to an already existing issue. That’s all it is doing. Pissing money and resource up against the proverbial wall whilst causing further harm. That’s not compatible with reducing harm at all.
A cruise liner emits more CO2 in 100 miles than a rocket launch does in its entirety.
Starlink may end up saving resources rather than using them.
Spaceship and it’s equivalents may be the key to space based solar power transmission, asteroid mining and Lagrange energy harvesting.
I’d rather have Musk and Bezos funding their own private space race and taking the world with it, than playing politics and buying social media.
The total payload of apollo was around a tonne. A manned mission with 3 people on a cometary orbit to mars will need several times that just in food. so thats the equivalent of several moon missions just to get the food needed into orbit let alone the oxygen, water etc plus the many tonnes of fuel needed plus of course the craft - and with the craft you have the problem that all that mass either has to be landed on mars and then take off again or be left in orbit and have a lander - more parasitic weight
Basically I think yo are talking the equivalent of a few hundred apollo missions in energy usage
As an engineer and scientist who’s involved with these efforts, I can’t begin to tell you how wrong you are
The problems aren't science and engineering related, that's the point I'm making. They are economic and social.
It would be interesting to work out how much fuel is required to get a spaceship back off Mars and back to earth.
Have you seen that big-ol' vacuum centrifuge they're testing for lobbing unmanned stuff into space? Would be relatively easy to build up on Mars....compared to shipping millions of tons of fuel, that is.
The problems aren’t science and engineering related, that’s the point I’m making.
Errmmm - yes they are. The engineering involved is hugely ahead of what we have now due to the length of the mission.
tjagain
Full Member
The total payload of apollo was around a tonne.
LOL! The payload of Apollo was over 43 tonnes. The CSM was over 28t and the LM was over 15t.
For context - that’s the weight of 4x 56 seat busses into lunar orbit on every launch.
A SVB can put the equivalent of a 787 into LEO.
Is that not the total weight? I am talking about payload.
Unless i read this wrong its a tonne
https://en.wikipedia.org/wiki/Apollo_command_and_service_module
Spacecraft type Capsule
Launch mass 32,390 lb (14,690 kg) Earth orbit
63,500 lb (28,800 kg) Lunar
Dry mass 26,300 lb (11,900 kg)
Payload capacity 2,320 lb (1,050 kg)
Total weight of Apollo on a Saturn V was ~3000t. The payload was the CSM, the LM and the crew. That weight was ~44t.
If the moon weren’t the target the SVB had a payload to LEO of ~120t.
Block 3 SLS will be 150t to LEO.
Starship is unclear. 120 to LEO for sure.
Edit, re-reads source
This is one area in which NASA's SLS rocket will up the ante on the Saturn V. In its initial configuration the SLS will launch with 8.8 million pounds of thrust, 15 percent more than the Saturn V.This will allow the SLS to send 27 tons of payload to the moon's surface. And the following configurations will be even more powerful, capable of carrying even greater payloads to the moon which will be needed for longer more sustainable space missions.
https://www.space.com/saturn-v-rocket-guide-apollo
Yes
We are just a bit at cross purposes. How much cargo along side the CSM and lander could be carried? a tonne? ie the weight of the people their equipment and stuff they used on the moon
3000 tonnes of saturn to put 44 tonnes of CSM and lander into moon orbit to carry a tonne of people and stuff
Errmmm – yes they are. The engineering involved is hugely ahead of what we have now due to the length of the mission.
I meant the problems with the environment on Earth.
Is LEO enough tho? Build the mars ship in LEO then it still needs a lot of fuel to get it into a cometary orbit
As I understand it, the problem isn't with it being 3,000 tonnes, its with it being 3,000 tonnes of manufactured equipment that got destroyed each time. If they can build reusable rockets and boosters, they'll just need to fill it up and send it back again which will be pretty cheap by comparison.
This will allow the SLS to send 27 tons of payload to the moon’s surface.
Which has to include the capsule it is in and all the motors and fuel for landing? so how much of that 27 tonnes is parasitic weight and how much is actually "stuff? half and half? less? More ?
then if you are using the moon as a staging post its all got to be boosted back into moon orbit - more fuel needed ( I know its a lot less than from earth)
No TJ - you said we’d need hundreds of launches, but that’s based on your misunderstanding of payload. The spacecraft weight is the critical aspect, not the crew weight . Ground to lEO capacity is the metric you need. A ROM figure for a reusable (several times) spacecraft to Mars would be 1500-2200t that could be accomplished with 10-15 launches, less if fuel is sourced on both the moon and Martian surface and even less if in-orbit manufacturing is used.
Daffy - you obviously know more than this SF reader 🙂
How many tonnes need to be put into orbit for a 3 person 2 year mars lander mission? How much fuel to boost the mars ship from LEO to a cometary orbit to mars, land and return?
edit - crossed posts 🙂 clearly not the hundreds of launches I guess ed then - dozens?
Any idea that we will colonise other planets is just bollocks.
I can't believe how closed minded some are being. I reiterate; 200 years ago we travelled by horse and cart. The thought of flight, let alone supersonic flight, or self driving cars, or a pocket computer you can use to talk to other people ..... mindblowing
Just because you don't have a solution to the very real problems identified, I find it inconceivable that solutions will not be found. Not in my lifetime, maybe not in another 200 years. And maybe we'll poison the planet and die out beforehand, I can't overlook that.
spacecraft weight is the critical aspect, not the crew weight
Of course - but there still must be some parasitic weight - the containers for the fuel etc? No?
What the heck are you talking about?
The payload of the lander isn’t important. It’s the payload of the rocket that is.
Once you know what the rocket can lift and to what altitudes, you can decide what to do with that capacity. Fly a long way, carry a lot of equipment, break orbit and enter another, etc.
Not in my lifetime, maybe not in another 200 years. And maybe we’ll poison the planet and die out beforehand, I can’t overlook that.
Earth will become basically uninhabitable by humans in 50ish years - rising temps, food and water unavailability leading to population crash and the end of our society. Humans won't be wiped out but will have no spare capacity for anything but survival. Its already starting to happen.
Sure, missions which require landing, orbit insertion, etc require more equipment, but it’s not parasitic, it’s just mission equipment.
What the heck are you talking about?
The payload of the lander isn’t important. It’s the payload of the rocket that is.
Yes - you put 120 tonnes into orbit. How much of that hundred tonnes is the stuff you need and how much is the tanks etc to hold it.
Your rocket puts 120 tonnes into LEO. thats its cargo capacity or payload. But you cannot just send fuel without something to contain it - same with O2 - needs a tank. Water - needs containment.
small % in that parasitic weight?
I don't think Earth will become uninhabitable. We are gradually fixing things, the worst they get the faster they'll get fixed. It'll end up significantly degraded, but it'll stabilise. Quality of life will drop, in traditional material terms and some others.
Earth will become basically uninhabitable by humans in 50ish years
that’s as big a pile of bollocks as I’ve ever heard from you.
Most studies show that temperatures will be 1.5-2deg higher and that many already hot areas will be inhospitable, placing 1-3bn people in difficulty. The difficulty with projections is that few people know how weather patterns will truly alter.
Earth will become basically uninhabitable by humans in 50ish years – rising temps, food and water unavailability leading to population crash and the end of our society. Humans won’t be wiped out but will have no spare capacity for anything but survival. Its already starting to happen.
It's getting frighteningly close, I agree. And I don't know why I have the faith given where we are now, but I still do, that science will find solutions.
Don't ask me to justify, that's why I call it faith.
Sure, missions which require landing, orbit insertion, etc require more equipment, but it’s not parasitic, it’s just mission equipment.
Gonna need a lot of equipment to mine dilithium crystals.