The tweet archive.

“@SpaceXUpdates Crew Dragon high altitude abort test”

“@DJSnM @DanAloni @Kell31213876 @Vadim15258417 @Erdayastronaut @sasor098 @AdamHugo @WayCharMar @fan_of_racing @bkent136 @macodiseas @katlinegrey Advanced, reusable rockets are all we need to become a multiplanet civilization. Once we have a city on Mars, interplanetary travel will create a forcing function for vast improvements in spaceflight.”

“@benoitdenayer @navincho @katlinegrey Essentially, yes. Great engineering talent, but should focus on reusable rockets for purpose of a permanent human base on the moon and self-sustaining city on Mars.”

“@katlinegrey SpaceX commercial 🚀 launch market share went from 0% in 2010 to 65% in 2018. Despite massive subsidies to Boeing/Lockeed, they have never won a fair competition against SpaceX for several years. https://t.co/sqAYCCcJtd”

“@martinengwicht @macodiseas @katlinegrey Exactly. That’s the critical point for Starship/BFR: more payload than the biggest rocket ever made, but for less money per launch than the smallest (orbital) rocket. Without something that lowers orbital flight cost by 100X, humanity will never be a multiplanet species.”

“@fan_of_racing @bkent136 @macodiseas @katlinegrey SpaceX Merlin architecture is simpler than staged combustion (eg SSME or RD), but it has world record for thrust/weight & thrust/cost engine. Raptor has better Isp, but I’m worried it may fall short on those two critical metrics.”

“@katlinegrey I have been chief engineer/designer at SpaceX from day 1. Had I been better, our first 3 launches might have succeeded, but I learned from those mistakes. https://t.co/3r6ZqEc30A https://arstechnica.com/science/2018/07/as-the-spacex-steamroller-surges-european-rocket-industry-vows-to-resist/3/”

“@FredericLambert @georgezachary I had to focus on solving a painfully large number of engineering & manufacturing problems at Tesla (especially) & SpaceX”

“SpaceX foundry casting Raptor engine manifold out of Inconel https://t.co/zWlqNwGj0R”

“@Erdayastronaut @John_Gardi @w0lfyxD @Robotbeat @SpaceX Yeah, but simpler. Needed for landing burn or engines will suck in a bubble.”

“@John_Gardi @w0lfyxD @Robotbeat @SpaceX Starship & Super Heavy will press tanks autogenously even in version 1. Very important, as helium costs more than oxygen on Falcon, even though liquid oxygen is 2/3 vehicle mass & helium weighs basically nothing.”

“@John_Gardi @w0lfyxD @Robotbeat @SpaceX True”

“@AstrumMining @SPEXcast @McMurchie @Robotbeat @John_Gardi @SpaceX Moon first, Mars as soon as the planets align”

“@SPEXcast @ikrbkv @MARINAVALOVA2 @alexmd2 @SpaceX On my bedside table”

“@ikrbkv @MARINAVALOVA2 @alexmd2 @SpaceX A biography on Korolev has center place in my study”

“@SPEXcast @McMurchie @Robotbeat @John_Gardi @SpaceX Just planning on keeping the public informed about progress & setbacks. Will be some RUDs along the way, but excitement is guaranteed!”

“@McMurchie @SPEXcast @Robotbeat @John_Gardi @SpaceX The goodwill of the public is critical to Starship’s success”

“@epoxy101 @Robotbeat @John_Gardi @SpaceX At least 10X cheaper”

“@SPEXcast @Robotbeat @John_Gardi @SpaceX Very dependent on volume, but I’m confident moving to Mars (return ticket is free) will one day cost less than $500k & maybe even below $100k. Low enough that most people in advanced economies could sell their home on Earth & move to Mars if they want.”

“@SpaceXFan97 @Robotbeat @John_Gardi @SpaceX Yes”

“@Robotbeat @John_Gardi @SpaceX This will sound implausible, but I think there’s a path to build Starship / Super Heavy for less than Falcon 9”

“@13ericralph31 @John_Gardi @SpaceX Close”

“@John_Gardi @SpaceX But not an extendable nozzle though, as that just saves length. Nozzle diameter is limited by body diameter.”

“@SpaceXFan97 @alexmd2 @SpaceX Much above 300 bar main chamber pressure means extreme oxygen preburner pressure of 700 to 800+ bar. Definitely pushing the limit of known physics.”

“@_cgp @SpaceX Propellant was not deep cryo. CH4 & O2 were just barely below liquid temp at 1 bar. In theory, Raptor should do ~300 bar at deep cryo, provided everything holds together, which is far from certain. However, only 250 bar is needed for nominal operation of Starship/Super Heavy.”

“@John_Gardi @SpaceX Yes, aiming for 380 sec Isp with vac nozzle. Maybe 382 if we get lucky.”

“@13ericralph31 @SpaceX I think 6 where we lit main chamber & several with only preburners”

“@johnkrausphotos @SpaceX About 11 secs”

“@alexmd2 @SpaceX Definitely! It’s amazing that the RD-170 & RD-180 engines held the record for so many decades. Excellent engineering.”

“Raptor reached 268.9 bar today, exceeding prior record held by the awesome Russian RD-180. Great work by @SpaceX engine/test team! https://t.co/yPrvO0JhyY”

“@rocketisfine @leo190102 I was simply too sexy for it https://t.co/vugJLyZVjI https://m.youtube.com/watch?v=P5mtclwloEQ”

“@Erdayastronaut @LytovchenkoSerg @John_Gardi Booster center of mass is much lower & more consistent (no payload mass to consider), so still biases towards engine first entry”

“@LytovchenkoSerg @John_Gardi @Erdayastronaut Rocket booster temperatures won’t go much above 600 Kelvin on hottest parts of main body & maybe around 1200K on base, which uncooled steel can handle. Starship is around 1700K for a Mach 25 entry, so needs shielding of some kind.”

“@Malcolmmarsman @Erdayastronaut Prob wise for version 1 to have legs or we will frag a lot of launch pads”

“@Erdayastronaut The Super Heavy booster is only needed on Earth, so think of this as just “Starship” & sometimes it needs a boost, hence Super Heavy”

“🔥🖤 SpaceX Engineering 🖤🔥”

“Raptor just achieved power level needed for Starship & Super Heavy https://t.co/NcqnAVWc35”

“@SpaceX https://t.co/sO2s0OcM4L https://www.whereisroadster.com/charts/”

“@jclishman @dguisinger @Erdayastronaut @DanielDavisA Will do, although SpaceX reddit is very well-informed. Really impressive analysis by some commenters.”

“First firing of Starship Raptor flight engine! So proud of great work by @SpaceX team!! https://t.co/S6aT7Jih4S”

“@TriTexan @SpaceX Yes”

“At @SpaceX Texas with engineering team getting ready to fire new Raptor rocket engine https://t.co/ACFM8AtY8w”

“@Trump_45th @SpaceX 7”

“@Archin50001 @AlexTheChemist @SpaceX Dammit! 😀”

“@AlexTheChemist @SpaceX Well, my past mistakes do seem extremely dumb, especially the ones where I mistakenly thought I was smart”

“@nickynaptime Rocket mass ratio is about the same for aluminum-lithium vs 301 stainless full hard at cryo, but latter costs way less, is tougher & doesn’t even need paint!”

“@SpaceXFan97 @wonderofscience @Treebeard1671 @Erdayastronaut @keego73 Still up to 31. Will probably fly with fewer initially in case it blows up.”

“@TriTexan @SpaceX Yes”

“Initially making one 200 metric ton thrust engine common across ship & booster to reach the moon as fast as possible. Next versions will split to vacuum-optimized (380+ sec Isp) & sea-level thrust optimized (~250 ton).”

“Preparing to fire the Starship Raptor engine at @SpaceX Texas https://t.co/8JCOi1BG6z”