tater

There is an environmental impact doc that was recently circulated that showed SS being moved horizontally, FWIW. As for Stoke, they really seem to be driven to accomplish the goals they set out in the timeframe they announce—so they throw around dates with more care. I really think they have a shot at flying fairly soon based on recent interviews I have heard with Lapsa.

I said no, and it's not a straw man until there are competing, reusable vehicles. (and SpaceX doesn't have a 100% reusable yet, it's a long pole ). Even partial reuse might be similarly cheap as 100% reuse, BTW. It just requires a really cheap stage 2 and fairings. Certainly compared to a huge vehicle like SS, a small vehicle optimized for low S2 cost might compete. It's my understanding that the prop costs for a SS stack are around a million bucks. The stack is said to be ~S100M. If it was good for 100 flights, then they'd have a cost of north of $2M/flight. If they mark that up to ~$4M, they're at roughly half of what an Electron launch costs to launch 320kg, even assuming a bespoke launch. Obviously they could throw in a bunch of other payloads that have their own tug stages to drag them to other orbits, and further reduce cost. If Stoke can fly ~5t payloads with a couple hundred grand worth of props, then we've got some real competition going—and like I said, I'd bet that Stoke gets to operational reuse first—They might be able to fly that same 320kg at an internal cost of a few hundred grand—charging less than even just the propellant costs of SS and still making money. So I am agreeing that size matters when we're comparing apples to apples, but my initial reply—all that matters is cost—was referring to a statement about the current/near-future launch market, even including partially reusable vehicles like NG. Once there is competition... it's still all about cost all things being equal (reliability, etc matters). Ie: it's still all about cost. As an aside, in the Dodd interview/tour, Bezos talks at some length about the trade of upper stage cost with and without reuse. I think he;s right that it's not at all clear that the additional cost for stage 2 reuse closes. With suitably efficient upper stage engine production (lower cost), throwing away upper stages actually looks attractive. Imagine reused SH, and an expendable "Starship" upper stage. If they get R3 prices down to ~$250k, even with 9 engines that's only $2.25M—the lion's share of S2 cost. Maybe they get away with fewer, all vac optimized and get it down closer to a million? So marginal cost is more like $3M expended? For 320kg (Electron), that's starting to look crappy, but for large payloads? A few of us have said something similar to Bezos here, that expendable is actually still worthwhile in some use cases, particularly upper stages (or in-space only reuse, like refillable tugs). We need BO working hard to cut costs, and idealy Stoke as well to start seeing what actual competition looks like. Unsure what Sierra Space can do with ULA, TBH (assuming they buy it).

It is still cheaper to send a single small package in a large, reusable airliner to the other side of the world—charging the customer the entire cost of the flight in labor/fuel/etc—than it is to have them buy a much smaller jet that is thrown away upon delivering the package. Rocket lab charges ~$7.5M for a launch. If Starship could deliver the same tiny payload to orbit for the customer and their cost is $2M, they can make money and still charge less. Yes, in which case cost is STILL the pnly thing that matters, but smaller, reusable vehicles will be less expensive. Small payload? Stoke will be cheaper (FWIW, I bet Stoke has reuse nailed before SpaceX, I think it's easier with their design). Still, that relies on competitors with reuse unless someone makes expendables so cheap throwing them away for small payloads is cost effective. A huge vehicle generating a new market is an unknown here, I agree. Maybe it does, maybe it doesn't. Reusable vehicles—assuming there are at least 2 competing companies with full reuse—massively reducing cost is another unknown. As launch costs spiral downwards, the market becomes less valuable, and they either need way more cargoes, or what's the point? It could be that 2 competing reusables only mildly reduce cost/kg because it's not in either company's interest to do so since their internal costs are so low, they make a boatload per launch at 2024 prices, or even half of 2024 prices (even if they could charge 1% of 2024 prices). If costs dropped 2 orders of mag, and so did retail price, an $8B launch business becomes an $80M business, lol. They'll need new customers.

Progress:

Wow.

All that matters is price. If it's actually reusable, and operational costs are less than any competing vehicle, "size" is completely irrelevant. If it uses a couple million in propellants and labor to reuse, that's the cost. Assuming full, rapid reuse for argument, sure, some partially reusable or even expendable vehicles might be cheapr to launch a single cubesat or something. So what?

~5.5 hours from now:

He's always been into it since college, actually. I've never doubted his sincerity, he just was not as personally involved, and it got back-burnered, I think.

Be-4 Isp is 340 (I assume vacuum Isp for SL engine). Be-3U is 445

339th landing

It's the most interesting place we can go that is close, and allows testing our abilities in that area to push some TRLs I guess. Most hab concepts for extended lunar stays have similar constraints to the same sort of facility on Mars—as you say, the radiation environment is harsh—but the same solutions for the Moon do apply to Mars (covering habs with regolith). Better to test solutions 3 days from home than over a year from home. The nominal point of Artemis is of course a "sustainable' lunar presence, and the hope is for work on ISRU using lunar water ice making the facility a propellant source.

Meanwhile, a new F9 stage 2 is in space, booster landed. It's tedious to have to edit x to twitter to get them to embed... wonder if the forum software ever catches up?

This. Wanting Apollo 2 at all is insipid. Do something new/useful, or don't bother. The only reason the first landing with 2 crew should even exist is to test equipment for real missions. Testing equipment that merely lands a couple people, or even 4 is similarly uninteresting. Assuming NG flies in September (big if), the notion of a program based on a system that is headed towards costing 6-7 BILLION per launch is nothing short of insanity. By the end of the year we'll have 2 cost effective medium lift vehicles (F9 and Vulcan), 2 cost effective heavy lift vehicles (FH and NG), and one super heavy lift vehicle (SS/SH)—assuming it is ever used with all or part expended. Then we have the one heavy that's too expensive to be useful (SLS Block 1), and future super heavy that's also grossly too expensive to be useful (SLS Block 1B). Nothing will ever make SLS cost effective, the sooner it's obviated, the better.

As I recall there was a number that might return that was set far lower than 100

25 min

Launch in a few seconds