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Joined 2 years ago
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Cake day: June 14th, 2023

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  • There are a few things that are different from what NASA has done in the past:

    1. SpaceX Rocket is the most powerful rocket ever, surpassing everything that NASA or anyone else has ever done.

    2. they are landing the rockets, with the aim of being able to recover them. If you skip the technicality that SpaceX first stage is suborbital but is part of an orbital launcher, that makes SpaceX the only entity who has achieved that, with some comparison to the Space Shuttle and Buran, though both were losing significant sections of the initial launcher, with very difficult repairs once on the ground.

    3. the cost of the launcher. In terms of capabilities, NASA’s SLS is probably close to Starship. However, it costs around $2B/launch, and nothing is recoverable. Starship is meant for low cost. It is estimated that the current hardware + propellant for a single launch is under $100M. With reusability, a cost per launch under $10M is achievable in the mid term (10 years I would say) once the R&D has been paid ($1.4B/year at the moment, I would guess the whole development for Starship will be $10-20B, so same if not less than SLS).

    4. the aim for high speed reusability - SpaceX aim is to launch as much as possible, as fast as possible, with the same hardware. While it is a bit early to understand how successful they will be (Elon was saying a launch every 1hr, which seem to be very optimistic, I would bet 6-12hrs to be more achievable). That was NASA’s original goal for the Space Shuttle, and they failed that.

    5. finally, orbital refueling means you have a single vehicle that can basically go anywhere in the inner solar system without much issues, and minimal cost.

    Also, what gets people excited are the prospects of what this enables. A 10-100x decrease in the access to orbit changes completely the space economics and opens a lot of possibilities. This means going to the Moon is a lot simpler because now you don’t need to reduce the mass of everything. This makes engineering way easier as you do not need to optimise everything to death, which tends to increase costs exponentially. And as for Mars, Starship is what makes having a meaningful colony there possible. Doing an Apollo like mission on Mars would have been possible for decades, but at a significant price for not much to show for. With cheap launch, you can just keep sending hardware there.


  • If you have fiber, it’s unlikely you will benefit from something like Starling. Transfer data wirelessly through a constellation of satellites will have running costs much higher than just having a fibre. That is unless you have to dog a trench or run a fibre on mast for km for just one customer, which is where Starling starts making more sense.

    Starling is for rural customers, mobile customers, and possibly an option to counter monopoly abuse by some Telco companies. But if you are in a city with fibre, then do use the fibre, that’s your better option.


  • The Oxford study is really good. But I can’t say the same about this article.

    A COP of ~2 is not great for a heat pump, calling this a triumph is really weird. But from a journalist saying that a COP above 1 means the heat pump “creates energy”, I am not sure I should have expected more.

    But what’s great is that this COP of 2, while bad, is not catastrophic. That’s still in territory where gas boilers are more cost efficient that a heat pump, but unless you are living in a place that is consistently under -10C for several months, then a heat pump has overall lower running costs than a gas boiler. And you are starting to hit pretty northern territories with this.

    What’s important is also to be able to store heat during the day so that the heat pump runs at its most efficient time. But that can unfortunately coincide with the higher consumption time, so the timing needs to be adjusted properly to avoid using it during consumption peaks.





  • We lose the communities from that instance, yes. And that’s why people want to make sure you don’t have one dominant instance on the threadiverse. But frankly that issue will be there unless you have a fully decentralised system.

    That being said, other instances will have a cache of the activities happening on this other instance. You can then fairly easily recreate it from this cache, and if you have a lot of storage, can also have a limitless cache.