1) This is “lunar tourism,” where an individual is using his own money to pay for a service from a private company. Asking what it will contribute to our knowledge of science is kind of like asking what your vacation to the French Riviera will contribute to science.sophiecentaur said:
Something like 90% because it goes into Starship development. That's not yet including the indirect effect of getting more people interested in science.sophiecentaur said:
Good old "fix problems on Earth first". Fix problems with stone tools first before working on metals!sophiecentaur said:
Yes and it would be just as silly and off topic.sophiecentaur said:
Wonder how far along we'd be if all the scientific advances of the last millenium or so were paid for solely from the scientists' pockets.sophiecentaur said:
Including or not new spaceship and spacesuit designs ?
How about an image from SOFIA ? 8 years worth of a ginormous telescope, operating from 40,000 ft. So, was the contraption that lofted the telescope to that altitude cobbled together by MIT students over a weekend ? (hint: 747's take longer than that to assemble)
"They" in this case being the billionaire who's funding the jaunt ; other philanthropic interests include a foundation that supports artists ; no specific mentions of supporting other countries in his Wikipedia bio.
Are you saying that there are no other 'costs' for a project like this? If I choose to burn a thousand tons of low grade coal, just because I can afford to buy it, would that make it OK? All actions have consequences and the 'right' thing is to consider the true cost / benefit.hmmm27 said:
Artemis did deliver some science projects/probes. so that saves individual rocket launches. https://www.nasa.gov/press-release/nasa-selects-new-instruments-for-priority-artemis-science-on-moonsophiecentaur said:
I don't think anyone would call Artemis a rich man's vanity project. A properly designed Moon Landing would / will have plenty of scientific justification. I'm not sure that the proposed crew is the best for that purpose but we shall see from any results they come up with and there is a meaningful forward plan for the programme.pinball1970 said:
I couldn't (easily) find which rocket booster will be used : SpaceX seems to have kerosene, methane and hydrazine engines available.sophiecentaur said:
I think we can stick with "every" : I find "many" people confusing. If I could've been arsed at the time (and not suspicious at all), I would've signed up for that (currently defunct) mission where they were going to lob people at Mars 4 at a time under the assumption that some of them would make it.
Starship uses methane and oxygen. The carbon footprint of that mission is negligible compared to its impact.hmmm27 said:
The dearMoon crew won't be inside the Raptor engines and fuel tanks either, what's your point?sophiecentaur said:
That probably indicates your age and circumstances. There are tens of thousands of people who skydive, dive, use recreational drugs but the median age is pretty low. To be honest, that was me when I was youngerhmmm27 said:
but I grew out of that stuff once other responsibilities kicked in. It's definitely not "every".I know there's a lot of re-usable stuff in modern space flight but the proportion of the footprint due to actual fuel, as opposed to the manufacturing footprint is probably similar to that for a domestic car. Not too dissimilar total mileage. People tend to forget that, as they do when they buy a new 'economical' family car.mfb said:
You piqued my curiosity so I did some very rough number crunching: Starship + super heavy has a propellant capacity of 4800 t (I’m assuming that’s metric tonnes). If we assume this is all methane (the conservative estimate omitting the oxygen), and that liquid methane has a density of roughly 400 kg/m^3 at its boiling point, then cranking through all the math, we end up with about 3 million gallons of methane. A straight shot to the moon and back is roughly half a million miles, giving a fuel efficiency of 1/6 mpg. (Of course this is meaningless. The ISS has completed over 100000 orbits of roughly 25000 miles since its launch, meaning it has travelled well over 3 billion miles. So even given several million gallons of fuel to combat orbital decay, it would likely be more efficient than any car on the road today.)hmmm27 said:
And it gets rid of a bunch of that potent GHG (GreenHouse Gas), Methane!mfb said:
My point is that there is often very little reason for humans actually being there, except for the 'because we can' philosophy. Time was when only a very few people actually went anywhere much unless it was strictly necessary. Nowadays the fashion is that people with enough money feel entitled to go anywhere. Look at the state of the paths to Everest summit - full of rubbish, left by careless 'adventurers'. Diving locations have been totally spoiled because of 'trippers'. The fashion of building Cairns on mountain paths has caused erosion (as well as boots which have strayed from the path). It happens all over the place.mfb said:
'Twas meant a little tongue-in-cheek, but yes, yes it does.sophiecentaur said:
Your points are valid IMHO. (Personally) I think a human Mars landing is premature : bulk up that Lunar-orbital station first ; then, that divot in Phobos looks like a neat place to set up a tent. Either way, tossing garbage into orbit is almost dumber than tossing garbage onto the ground.sophiecentaur said:
Starship is designed to be fully reusable, and dearMoon will only fly after SpaceX has routinely reused both stages many times. The main carbon footprint will be the fuel used for that mission.sophiecentaur said:
It doesn't get the methane from the atmosphere. It's sourced from natural gas, although SpaceX wants to produce some from atmospheric CO2 and water.Tom.G said:
That's a politician's response. The real carbon footprint includes manufacturing divided by the number of trips it's used for. However you look at it, that's significant (as with your family car). For a valid choice of this sort of action, all the factors are relevant. Enthusiasts for anything tend to shy away from this sort of analysis. Heart can easily rule head.mfb said:
There is nothing political in my response. "The main carbon footprint will be the fuel" is a purely technical response, and it answers your concern about manufacturing. It's negligible compared to the fuel used, and I also explained why: Because the vehicle gets used often.sophiecentaur said:
Are the carbon-emissions saved by recycling applied to the ship ? or to the new-build bridge, building structure, bicycles, whatever. Same for cars, I suppose.sophiecentaur said:
The environmental impact of all the spaceships in the world is orders of magnitude less than that of pretty much anything else.
Your figure is from a source which may well be biassed in favour of the motor car industry (?).mfb said:
What do you mean by "often"? Once every six months for a few years would be hopeful and the actual carbon cost of refurb each time will be significant. Certainly more than the proportional cost of a yearly service for a motor car. The label 're-usable' will almost certainly be there for political reasons to some degree.mfb said:
True but is that relevant? The coal burned in an individual old fashioned power station is a tiny fraction of all our pollution. Does that justify it if the user in a developing country has no other way of getting electricity? Whataboutery is seldom a good argument. In the end it's about priorities, personal decisions and responsible behaviour.hmmm27 said:
I agree, maybe a mentor can split that discussion off and stick it in General Discussion where it belongs.mfb said:
Which claims are actually "wrong" please? Your and my sources for footprint disagree by a factor of more than ten. Are you sure you are right overall? I realise that you are far more keen on space travel than I but that doesn't facts about impact.mfb said:
I think we need some really good rallying power now to restore 'faith' and trust in science and engineering in general, so we could continue to support fusion research (among many others) for a few more decades till they bear fruit.sophiecentaur said:
That lull (iirc) was because the public lost interest (really not much to see and not good reliability, early on) and also because Apollo established the US superiority over the USSR in technology. These days, the missions can be presented to the public well enough to maintain their interest and reliability (safety) seems to be much improved. Possible use of space for military purposes is almost global now.Rive said:
SWOT is about to launch (NASA coverage) and the commercial satellite is still on track for a launch in about 10 hours, but Starlink was moved to be a day after that.mfb said:
I'll ignore all the car stuff and other things unrelated to spaceflight to stay on topic:sophiecentaur said:
Given that this is a significant share of Starship development, which is critical for Artemis... no, definitely not.sophiecentaur said:
You can learn all that from a name? What is Boeing's Starliner doing then?sophiecentaur said:
Even Falcon 9 boosters make multiple flights per year already, and they are the first reusable system SpaceX designed. Starship is designed for full and rapid reuse, without refurbishment. Your "hopeful" case is far worse than the old system?sophiecentaur said:
Wrong decade.sophiecentaur said:
It's not whataboutism. The atmosphere doesn't care about individual emissions it only cares about total global emissions. Comparing an individual house, car, power plant or rocket to each other is just a red herring. What's needed is to assess the relative impact of all of each. Power plants are the worst offenders, so changing the way we do power plants in general will have the biggest impact. Next is cars/trucks/ships (land transportation), next is heating. Space travel is way, way down on that list. Maybe someday it will be significant, so we'll need to make sure all rockets are fueled by electrolysis of water, but not yet.sophiecentaur said:
As long as "puts out" includes all manufacturing, servicing and transport contributions. Choosing what and what not to include is advertisers' technique and not good Engineering.russ_watters said:
That could be a good idea; go for it. However, along the same lines as Health and Safety matters, environment should at least have a presence in any discussion involving large amounts of energy.russ_watters said:
I agree, lifecycle emissions include manufacturing/servicing, but with a really, really big caveat: most of those indirect (not from the fuel) lifecycle emissions are pass-through from other sectors; energy and transportation. So if you fix those sectors, the indirect emissions go way, way down.sophiecentaur said:
Indeed. Public transport is often a far more economical solution to people getting to work than driving themselves in a year old family car.russ_watters said:
Depends on whether you include the value of time.sophiecentaur said:
I don't mean [emissions] cost per passenger or ton-mile (yes, cars are the worst at that too), I mean hours of use per year or lifetime. Truck, ships, planes, and yes trains all are operated much more than a car. Google tells me a truck gets 2-3x the distance lifespan of a car. So, for example if manufacturing emissions is 20% of a car's lifecycle emissions it might be 7% of a truck's. I'd have to do some research (a quick google doesn't find this info), but I suspect that the manufacturing emissions are only very significant for a car, and aren't for any other major form of transportation - including a hypothetical re-usable rocket.sophiecentaur said:
The impact of space exploration on global warming is complex and multifaceted. On one hand, space exploration has contributed to our understanding of Earth's climate and how it is changing. Satellites and other space-based technologies provide valuable data on factors such as temperature, sea level rise, and carbon dioxide levels. On the other hand, the process of launching rockets and other spacecraft into orbit releases greenhouse gases and contributes to air pollution. Additionally, the resources and energy required for space exploration could potentially be used to address global warming instead.
Space exploration has both positive and negative impacts on the environment. On the positive side, space technologies have helped us better understand and monitor our planet's environment, and have even led to advancements in clean energy and sustainable living. However, the process of launching spacecraft and maintaining space infrastructure can also have negative effects. Rocket launches release pollutants into the atmosphere, and space debris can pose a threat to Earth's environment and ecosystems.
Space exploration has a significant economic impact, both globally and locally. It creates jobs in various fields such as engineering, manufacturing, and research. It also drives technological advancements that can be applied to other industries, leading to economic growth and innovation. Additionally, space exploration can also lead to the discovery of valuable resources on other planets and asteroids, which could have economic benefits in the future.
Space exploration has had a profound impact on society. It has inspired generations of people to pursue careers in science and technology, and has sparked curiosity and wonder about the universe. It has also led to advancements in communication and navigation technologies, making our lives easier and more connected. Furthermore, space exploration has brought countries together in international collaborations, promoting peace and cooperation.
As with any pioneering endeavor, space exploration comes with risks. The most significant risk is the potential for accidents or malfunctions during space missions, which could result in loss of life or damage to equipment. There is also the risk of creating more space debris, which could pose a threat to future space missions. Additionally, there are ethical concerns surrounding the potential exploitation of resources on other planets and the impact on indigenous life forms, if they exist.