RealKerbal3x

Welcome! I think you'll like it here.

230t thrust is for the new Raptor 2 iteration, the wiki thrust is for the previous version. The current version of Starship has 6 Raptors (3 sea-level, 3 vacuum), increasing to 9 engines later on (3 sea-level, 6 vacuum). All engines will be running during the second-stage ascent to reduce gravity losses. Most upper stages have a TWR < 1 and get to orbit just fine. Starship is no different.

That was for fully expendable ITS, a very different and much larger vehicle.

When Starship's max reusable payload mass is quoted as 150t, that doesn't include the mass of the vehicle itself. It can put itself + 150t of payload into orbit.

This belongs here

So, looks like Aerojet Rocketdyne has put together a proposed Mars crew mission architecture. Not sure if this is an internal leak, but it's an interesting read nonetheless. The link doesn't work unless you open it in a new tab, and then copy and paste the link again (for some reason). TL;DR in case you can't access it: There are two proposals for this architecture, one using nuclear thermal propulsion and the other nuclear electric propulsion. They both involve constructing a transfer vehicle in Earth orbit, though they differ in the number of launches. The launch vehicles used are SLS Block II (for crew and high-value cargo, eg NTR engines), New Glenn (for transfer vehicle truss segments) and Starship (for refuelling). Initial missions are short-stay (30 days on the surface), eventually evolving to long-stay missions (450 days) The overall mission goal is "the eventual human settlement of Mars", with each surface mission contributing to the construction of an outpost. The PDF states reusability as an important element of the architecture, though the crew and cargo surface landers are still single-use. The first human steps on Mars would take place in 2037 under this plan. Overall this architecture seems a little short-sighted to me. Starship is used heavily, but only for orbital refuelling - Mars descent and ascent still rely on small expendable vehicles, limiting surface elements like habitats or rovers to 20t. Starship is designed to land 100+t payloads on Mars, and this system assumes that it works as intended, so why not use it for that? It also assumes that SLS Block II becomes a thing, continues to operate into at least the late 2040s, and is capable of multiple launches per year. I'd bet on a commercial vehicle being available by then. Thoughts?

Looks more like a camera exposure change to me, you can see the gantry behind the test stand get darker at the same time as the plume becomes pinker. In general, I'm skeptical of insider sources. From what I've seen, their claims sound plausible, but are either completely unverifiable, or are simply extrapolations of information we already know. Occasionally, information we get from them is directly contradicted by what we see, or things Elon says (eg, the whole 'B4 isn't for flight' thing, or 'S21 will have the new design forward flaps'). Of course, we could chalk this up to SpaceX's flexible decision-making process, but in many cases that seems to imply that they decide to do something before backtracking on that decision within a matter of days. Until we see things officially confirmed, I prefer to err on the side of caution.

I'm sorry, I can't hear any of you over the sound of my GPU sobbing. (jokes aside, awesome work team!)

In typical sci-fi, spacecraft basically fly like aircraft. They can pretty much fly in any direction they choose, and they slow down/stop if their engines are disabled. IRL spacecraft are a lot more limited. Changing trajectory is possible, but unless you have some sort of far-future torch drive, a maneuver like a 90° turn - something that a TIE fighter pilot wouldn't think twice about - is out of the question. Of course, real spacecraft can orient themselves any way they want, but that doesn't necessarily mean they're heading in that direction. If we had spacecraft that could just point and go, space exploration would be a lot simpler. But we have to deal with orbital mechanics.

The chopsticks have been planned since late 2020, long before S20 even begun construction. It was definitely built with them in mind. Also: new NSF article, with pics of Raptor 2! https://www.nasaspaceflight.com/2022/01/raptor-2-starbase-update/

lol look at past me being all optimistic and stuff I'll try and do last year's resolution this year I guess.

More booster progress:

While we were all distracted, some booster action (B4 aerocovers, at long last!)

There seems to be enough air on Laythe's surface for kerbals to breathe, since if you remove their helmets they're just fine. Though I'm not sure how realistic this is - perhaps the environment would require an oxygen mask for longer periods spent outside, or particularly strenuous work.

Plants on Laythe's seafloor might be interesting. With the lack of light at the bottom of the oceans they wouldn't be living off photosynthesis, but - if Laythe is warmed by tidal heating and volcanism as I speculated - they could make a living around deep-sea geothermal vents. But because we see no obvious evidence of life on land, the most complex life I would expect to see on Laythe would be single-celled algae. Maybe we could even catch glimpses of algal blooms from space.

With how close Laythe is to Jool, I would imagine that its relatively clement temperature is a result of tidal heating, and possibly active plate tectonics/volcanism. We see this happening on Jupiter's innermost moon Io, which is literally covered in hundreds of active volcanoes due to the gravitational tug of its parent body. Given that Jool and its moons are so close together, Laythe probably experiences significant tidal forces from not only Jool but also Vall and Tylo (and perhaps from Pol and Bop too). I think this can definitely account for how warm Laythe appears to be in-game. As for liquid water, Laythe's oceans are most likely salty - probably much saltier than Earth's (or presumably Kerbin's). Salt lowers the freezing point of water by preventing water molecules from packing together as easily. As for how it got all of that water, perhaps Jool's gravity well captured a bunch of comets early in its history, when Laythe and the other moons were still forming. Or, more likely, maybe Laythe was formed elsewhere in the Kerbol system (probably closer to where Kerbin is now), accumulated its water there, and was later captured by Jool. The abundance of oxygen in Laythe's atmosphere could imply that it has some kind of simple photosynthetic life in its oceans. While I don't believe this is ever explicitly shown via science results, it seems like the explanation that requires the least assumptions - Occam's razor. Life doesn't necessarily need to have evolved on Laythe - given the relatively low escape velocities of the compact Kerbol system, panspermia from Kerbin is a real possibility. Laythe is one of the most interesting bodies in the Kerbol system - I really hope some of this gets explored in more depth in KSP2.

Nice diagrams showing the chopsticks' range of motion. The area where a catch is possible is bigger than it appears!

Passed Max Q

There's only one Thread of the Year per year. Unless you mean previous years' TOTYs, in which case they can be found earlier in the announcements section of the forum.

Congrats to @The Aziz, your thread is such a useful resource

Go Webb!

Deep breaths

No. But they did award it a major contract. It deserves some recognition given its major role in Artemis. NASA isn't contracting Starship as a launch vehicle, they're contracting it as a lunar lander. Of course, the contract requires it to act as a launch vehicle, but only because SpaceX bid the entire system - Starship isn't launching the lander, it is the lander. NASA's process for qualifying the vehicle would be the same had they chosen one of the other bidders, despite Starship's architecture being so unconventional. Even if you ignore the large number of Starship test flights SpaceX intends to conduct on its own dime, the vehicle will be 'rated' in a conventional sense long before it flies for HLS or even other NASA payloads thanks to the qualification milestones for the contract. They'll be flying more than two test flights before any payload gets onboard, never mind NASA. This isn't a concern for the HLS contract, because Starship crewed operations will only happen in cislunar space. Crew will not launch or land at Earth with the current arrangement. If/when Starship ends up flying end-to-end crew missions for NASA, they may require a launch escape system. In that case, SpaceX will have to develop one. NASA may instead choose to trust Starship's launch record and reliability, which it will presumably need to have accrued by the time it's flying crew. The latter is the option SpaceX seems to be going for, but any crewed launch/landing of Starship is several years away at best, so all we can do is wait and see.