RCgothic

PR's outgoing governor has committed to rebuilding Arecibo better than before with a larger aperture and more powerful radar. They've released $8m for cleanup. It's the beginning of something I guess, and I hope it continues.

SN10 is getting stacked! Nearly ready to go even before SN9's flight!

Neither SpaceX nor Blue Origin were first to land a rocket propulsively. Blue Origin was founded in 2000. SpaceX was founded in 2002. Blue Origin started hop tests in 2006. SpaceX started launching Falcon 1 in 2006. SpaceX first put a payload in orbit in 2008. SpaceX started launching Falcon 9 in 2010. SpaceX berthed a spacecraft to the ISS in 2012. SpaceX started hop tests with Grasshopper in 2012. SpaceX upgraded Falcon 9 to v1.1 in 2013. SpaceX started hop tests with F9R Dev-1 in 2014. Blue Origin started high altitude testing with New Shepherd in 2015. Blue Origin first landed New Shepherd from high altitude in 2015. SpaceX upgraded Falcon 9 to FT in 2015. SpaceX first landed an orbital class booster propulsively in 2015. Blue first reflew New Shepherd in 2016. SpaceX first reflew Falcon 9 in 2016. SpaceX upgraded Falcon 9 to Falcon Heavy in 2018. SpaceX upgraded Falcon 9 to Block 5 in 2018. SpaceX started hop tests with Starhopper in 2019. SpaceX were the first to fly a full flow staged combustion engine in 2019. SpaceX flew crew to the ISS in 2020. SpaceX started hop tests with SN5 and SN6 in 2020. SpaceX started belly flop tests with SN8 in 2020. Blue Origin has launched 3 New Shepherd vehicles a total of 13 times and landed 12 times, including 12 consecutive landing successes. NS-3 has 7 launches and landings over 2 years 10 months. SpaceX has launched rockets from the Falcon family 106 times with 104.5 successes, 1 in-flight failure and 1 pre-launch failure. Cores have landed successfully 70 out of 80 attempts, including 20 consecutive successes. Both B1049 and B1051 have 7 launches and landings with B1051 taking 1 year 9 months to do so. I hope that settles things.

NSF has a new article on SN9's test and flight program: https://www.nasaspaceflight.com/2020/12/starship-sn9s-test-series-targets-new-years/

Interesting shot of the damage. Construction near the high bay. Pad C? At the old oil well.

I don't think modular Saturn really works as a concept. The only common stage was S-IVB, an upper stage on both. S-II as a 1st stage would never get off the launch pad. You need a different 1st stage for each configuration. Core+SRBs is a very cheap way to get variable performance. Having a common upper and lower core diameter also reduces tooling costs. This is why the "Heavy" configuration of multiple cores also works quite well.

Whilst I'm not sure if individual Merlins have flown/fired more times than SSMEs, I believe the SSMEs were completely overhauled between flights whereas Merlins apparently needs little more than cleaning fluid.

You'd have thought. But apparently it really doesn't like being exposed to solar radiation.

I saw this discussed today on Twitter. The foam shedding situation was described as like "popcorn". Probably not the best idea after all.

Random musing I think probably doesn't deserve its own thread: Space Shuttle would have been better with Kerolox Main Engines. My reasoning: 1. No insulation foam. 2. RP1 up top would prevent falling ice. 3. Extreme reusability of Kerolox engines have been demonstrated. 4. It doesn't need to go BLEO so low ISP isn't a handicap. 5. Smaller External Tank. Yes it would be about 700t heavier on the pad, but it'd still be lighter than Saturn.

SN9 is on the move:

Although actually, by stunting HLS funding Artemis is going to get pushed back so maybe an SLS might be available for clipper after all. It's all a bit Machiavellian.

I've asked on Twitter but I'm not fully clear - are the bid amounts total for the next phase of development? I.e. divided over years it at least *somewhat* matches the proposed funding. Or is it an annual dev cost and the proposed funding is therefore a joke?

Ok, wow. Maybe NT aren't the front runners after all! On that budget I think SpaceX is the only realistic prospect.

In other SLS news: SLS won't be available. It can't be spared from Artemis.

4th time lucky?

News round up.

Pretty cool

20 consecutive landings despite failures earlier in the year is pretty impressive:

If you vaporise the ice chunk then its water vapour atoms will impact the rear of the cylinder with the same momentum transfer as the solid lump of ice. If you can draw an imaginary border around your system such that nothing crosses that boundary, then that system has not exchanged momentum with its environment and shall not be moving today.

They aren't going to replace the failed PDU on Orion because it's too hard to access and the risk of collateral damage exceeds the risk of flying without one of the capsule's redundancies. https://blogs.nasa.gov/artemis/2020/12/17/artemis-i-orion-progress-update/