# Continuing discussion of SpaceX launches \[edited title\] **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [December 22, 2015, 12:37am UTC](https://boards.straightdope.com/t/continuing-discussion-of-spacex-launches-edited-title/741048 "2015-12-22T00:37:01Z")\ **Posts on this page:** 20\ **Page:** 58
**Author:** ![shh1313](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/shh1313/32/8020_2.png) [@shh1313](https://boards.straightdope.com/u/shh1313)\ **Post date:** [March 10, 2021, 2:38am UTC](https://boards.straightdope.com/t/continuing-discussion-of-spacex-launches-edited-title/741048/1141 "2021-03-10T02:38:03Z")
I originally did link to an article. I don’t know why it isn’t in my post. Anyway that was mentioned in the article. ---
**Author:** ![shh1313](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/shh1313/32/8020_2.png) [@shh1313](https://boards.straightdope.com/u/shh1313)\ **Post date:** [March 10, 2021, 2:40am UTC](https://boards.straightdope.com/t/continuing-discussion-of-spacex-launches-edited-title/741048/1142 "2021-03-10T02:40:15Z")
Thank you… ---
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [March 10, 2021, 2:40am UTC](https://boards.straightdope.com/t/continuing-discussion-of-spacex-launches-edited-title/741048/1143 "2021-03-10T02:40:32Z")
> [@Sam\_Stone](#): > > The header tank in the nose already fills the space, and because it’s there for weight and balance it can’t be moved. It’s also just LOX, isn’t it? The LOX header is in the nose. The methane header is at the common bulkhead between main LOX and methane tanks. Neither can be moved, as you say. An early rotation might not help if the sloshing collapses the ullage. In fact I wonder if there’s a chance of the tank itself collapsing due to outside pressure, something like this: [![](https://img.youtube.com/vi/j0TQxYemrgg/maxresdefault.jpg "Atmospheric pressure crushes 220 litre drum (Experiment)") ](https://www.youtube.com/watch?v=j0TQxYemrgg&t=112) ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [March 10, 2021, 2:56am UTC](https://boards.straightdope.com/t/continuing-discussion-of-spacex-launches-edited-title/741048/1144 "2021-03-10T02:56:18Z")
As long as we’re imploding things: [![](https://img.youtube.com/vi/VS6IckF1CM0/hqdefault.jpg "Vacuum Implosion") ](https://www.youtube.com/watch?v=VS6IckF1CM0) ---
**Author:** ![Frodo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/frodo/32/302_2.png) [@Frodo](https://boards.straightdope.com/u/Frodo)\ **Post date:** [March 17, 2021, 1:45pm UTC](https://boards.straightdope.com/t/continuing-discussion-of-spacex-launches-edited-title/741048/1145 "2021-03-17T13:45:57Z")
According to this: [Starship SN11 | Medium Altitude Test Flight | Everyday Astronaut](https://everydayastronaut.com/starship-sn11-medium-altitude-test-flight/) SN11 may launch on Saturday. ---
**Author:** ![mikecurtis](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mikecurtis/32/3284_2.png) [@mikecurtis](https://boards.straightdope.com/u/mikecurtis)\ **Post date:** [March 26, 2021, 11:46pm UTC](https://boards.straightdope.com/t/continuing-discussion-of-spacex-launches-edited-title/741048/1146 "2021-03-26T23:46:05Z")
> **[Falling SpaceX debris puts on a light show in the sky](https://www.space.com/spacex-falling-rocket-debris-light-show)** > > If you live in the U.S. Pacific Northwest, you may have seen what looked like a strange "meteor shower" streaking across the sky last night (March 25). But that was no meteor, it was likely SpaceX debris falling and burning up in Earth's atmosphere,... > If you live in the U.S. Pacific Northwest, you may have seen a strange meteor streaking across the sky Thursday night (March 25). But that was no chunk of asteroid or comet — it was likely SpaceX debris falling and burning up in Earth’s atmosphere, experts say. ---
**Author:** ![N9IWP](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/n9iwp/32/3154_2.png) [@N9IWP](https://boards.straightdope.com/u/N9IWP)\ **Post date:** [March 30, 2021, 1:19pm UTC](https://boards.straightdope.com/t/continuing-discussion-of-spacex-launches-edited-title/741048/1147 "2021-03-30T13:19:57Z")
SN11 launched OK in the fog, and climbed to ~10km. Successful belly flop. Sometime during relight – kaboom at +5:49 NASASpaceflight recorded some debris landing. Brian ETA Eric Berger tweeted that belly flop may not have gone OK ---
**Author:** ![Sam\_Stone](https://avatars.discourse-cdn.com/v4/letter/s/ecccb3/32.png) [@Sam\_Stone](https://boards.straightdope.com/u/Sam_Stone)\ **Post date:** [March 30, 2021, 1:26pm UTC](https://boards.straightdope.com/t/continuing-discussion-of-spacex-launches-edited-title/741048/1148 "2021-03-30T13:26:34Z")
I am baffled why SpaceX would carry out a test flight in zero visibility. Looks like the rocket exploded, taking out all the vehicle data, while ground cameras were totally obscured. I wonder how much usable data they will get out this? ---
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [March 30, 2021, 7:12pm UTC](https://boards.straightdope.com/t/continuing-discussion-of-spacex-launches-edited-title/741048/1149 "2021-03-30T19:12:53Z")
Starship is streaming back thousands of channels of telemetry constantly. None of that requires recovering the vehicle, and a long-distance camera feed tells them nothing that the telemetry doesn’t. As an aside, amateurs have had some success in capturing and decoding Starship telemetry: [https://www.r00t.cz/Sats/Starship](https://www.r00t.cz/Sats/Starship) The good stuff is probably encrypted, though. ---
**Author:** ![Sam\_Stone](https://avatars.discourse-cdn.com/v4/letter/s/ecccb3/32.png) [@Sam\_Stone](https://boards.straightdope.com/u/Sam_Stone)\ **Post date:** [March 30, 2021, 8:49pm UTC](https://boards.straightdope.com/t/continuing-discussion-of-spacex-launches-edited-title/741048/1150 "2021-03-30T20:49:02Z")
Well, the telemetry only works until the anomaly. There is a LOT you can learn from cameras and video - which is why every rocket launch has cameras everywhere. For example, the failure of _Challenger’s_ side booster O-Ring was discovered because of the visible jet of flame coming from the area before the explosion. Even visually recording the explosion itself can sometimes tell you things that you’d never get from telemetry, such as where the weakest points might be on the rocket. I’m not saying you can’t get good information with telemetry, I’m saying that there is also information to be had visually, and it seems odd to forego that rather than just wait a couple of hours for the fog to dissipate. I did hear the SpaceX announcer say that the critical part of the test today was the transition to the ‘skydiver’ orientation. That’s been successful every time, but maybe SpaceX knows aomething we can’t see, and it concerns them. So one answer could be that they knew they weren’t going to land successfully anyway, but needed the flight to work out the aerodynamics at 10k. Maybe they didn’t want to redesign the gear for Sn11, so a successful landing wouldn’t happen, so they didn’t care about ground fog. But it still seems a bit reckless to me. The goal of test flight is to gather as much information you can, from every source you can muster. And if there had been an emergency (say a fire caused by falling debris), you don’t want to deal with it in zero visibility. ---
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [March 31, 2021, 3:21am UTC](https://boards.straightdope.com/t/continuing-discussion-of-spacex-launches-edited-title/741048/1151 "2021-03-31T03:21:46Z")
It wasn’t zero visibility. And the on-vehicle cameras were mostly working. Rumors are that the flight termination system engaged. That would explain why it didn’t even make it to the ground. If the skydive wasn’t working _quite_ as planned, maybe the vehicle left its descent corridor and had to be destroyed. Although a landing would have been nice, SN11 was the last of the first series of Starship vehicles. SN12-14 no longer exist, and SN15 will be the first in the next series, with lots of improvements. Allegedly, the Raptors have also undergone a series improvement that requires a new thrust dome, and the engines on SN11 were basically the last examples of the previous model. So really I’m not sure that SpaceX cared about SN11 too much overall. Not that I think the crash was intentional or anything, just that their focus now is on SN15. ---
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [April 5, 2021, 10:17pm UTC](https://boards.straightdope.com/t/continuing-discussion-of-spacex-launches-edited-title/741048/1152 "2021-04-05T22:17:21Z")
Small update from Musk: > “Hard start”, in understated aerospace-speak, means “the combustion chamber had too much propellant in it before ignition, and so upon ignition it exploded”. Hard starts can be caused by leaks, problems with the start sequencing, a malfunctioning igniter, etc. They really need this part to be reliable if they’re ever going to launch humans. So they need to fix the leak, and the design process that led to the leak, and the QA process that didn’t catch it, and the software that didn’t detect the fried avionics, and avionics that were in a location that could be fried, and so on… ---
**Author:** ![Fiendish\_Astronaut](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/fiendish_astronaut/32/3295_2.png) [@Fiendish\_Astronaut](https://boards.straightdope.com/u/Fiendish_Astronaut)\ **Post date:** [April 8, 2021, 9:55am UTC](https://boards.straightdope.com/t/continuing-discussion-of-spacex-launches-edited-title/741048/1153 "2021-04-08T09:55:32Z")
SN15 is next off the rank and apparently boasts over 100 improvements, including to the engines. Hopefully we will see more reliability. ---
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [April 12, 2021, 7:39am UTC](https://boards.straightdope.com/t/continuing-discussion-of-spacex-launches-edited-title/741048/1154 "2021-04-12T07:39:34Z")
In case anyone’s interested in some reading material, Eric Berger’s book _Liftoff: Elon Musk and the Desperate Early Days That Launched SpaceX_ came out recently: > **[Amazon.com: Liftoff: Elon Musk and the Desperate Early Days That Launched SpaceX...](https://www.amazon.com/Liftoff-Desperate-Early-Launched-SpaceX-ebook/dp/B088FQK2K2)** > > Liftoff: Elon Musk and the Desperate Early Days That Launched SpaceX - Kindle edition by Berger, Eric. Download it once and read it on your Kindle device, PC, phones or tablets. Use features like bookmarks, note taking and highlighting while reading... I’m a few chapters in and it’s a good read. So far it’s the most in-depth look at the personalities _aside from Musk_ that I’ve seen (Ashlee Vance’s biography covers Musk). So if you’re interested in Hans Koenigsmann, Gwynne Shotwell, Tom Mueller, and a bunch of others, Liftoff covers them all. Some crazy times back then. Berger seems to have done his homework and researched the heck out of it, too. Some of the stories I’d have a hard time believing if they came only from Musk but even the wilder ones are corroborated by several people. ---
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [April 23, 2021, 10:10am UTC](https://boards.straightdope.com/t/continuing-discussion-of-spacex-launches-edited-title/741048/1155 "2021-04-23T10:10:40Z")
Looks like a flawless launch of the Crew-2 mission. Reused booster, too (not to mention a good landing). The crewmembers wrote their initials in the soon. Despite having watched several dozen launches, I still find the speeds and accelerations remarkable. Just watching the velocity go up–the hundreds digit (in km/s) is another 60 mph each time it ticks up. At a certain point it’s going up more than once a second. Imagine a car which doesn’t just have a \<1 second 0-60 time, but can do that every second for _several minutes_, ending up at 27,000 km/h. It’s just nuts. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [April 24, 2021, 4:46pm UTC](https://boards.straightdope.com/t/continuing-discussion-of-spacex-launches-edited-title/741048/1156 "2021-04-24T16:46:36Z")
Interesting (and pretty) **[NASA APOD vid](https://apod.nasa.gov/apod/ap210424.html)** on the recent Crew-2 launch. Shame NASA doesn’t set up their web pages so Discourse can show a preview box. ---
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [April 24, 2021, 6:13pm UTC](https://boards.straightdope.com/t/continuing-discussion-of-spacex-launches-edited-title/741048/1157 "2021-04-24T18:13:28Z")
That is a pretty video. You can just link to the YouTube video directly: [![](https://img.youtube.com/vi/badXkJ6BnOs/maxresdefault.jpg "Streak and Plume from SpaceX's Crew-2 Launch") ](https://www.youtube.com/watch?v=badXkJ6BnOs) In general, launches just after dusk or just before dawn are the loveliest, because the sky is dark but the rocket is illuminated as soon as it gets a few tens of kilometers up. On that one, you can also see the first stage landing far off in the distance. I apologize for the shoddy camera work, but this is some video I took of a Vandenberg SpaceX launch a few years ago: [![](https://img.youtube.com/vi/sebQiMgGuVM/maxresdefault.jpg "SpaceX SAOCOM 1A Just after stage separation") ](https://www.youtube.com/watch?v=sebQiMgGuVM) The top bright dot is the first stage maneuvering to land, while the lower dot is the second stage. The colorful “nebula” was absolutely gorgeous in real life. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [April 24, 2021, 6:16pm UTC](https://boards.straightdope.com/t/continuing-discussion-of-spacex-launches-edited-title/741048/1158 "2021-04-24T18:16:18Z")
Yeah, I could’ve, maybe should’ve. linked to the YouTube directly. But I wanted to share NASA’s commentary and also introduce folks to APOD. Most of the space nerds in this thread probably know about it and visit daily, but there’s always somebody for whom it’s a welcome find. ---
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [May 2, 2021, 8:27am UTC](https://boards.straightdope.com/t/continuing-discussion-of-spacex-launches-edited-title/741048/1159 "2021-05-02T08:27:21Z")
And another [completely flawless landing](https://youtu.be/6O-N5E6x0uc?t=3301) of astronauts on a Crew Dragon. Although there was never any reason for concern, I always find myself anxious during the comms blackout. In a way it’s funny that the most dangerous segment of the whole thing, with the highest forces and temperatures, also happens to be the part where we have the least information about what’s going on. It’s incredibly nerve-wracking! There were come cool IR tracking shots of the capsule. Though at one point they show a shot with multiple bright streaks, which again was concerning. Not quite sure what that was; maybe the Dragon’s trunk burning nearby. ---
**Author:** ![Bijou\_Drains](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bijou_drains/32/2814_2.png) [@Bijou\_Drains](https://boards.straightdope.com/u/Bijou_Drains)\ **Post date:** [May 3, 2021, 2:27pm UTC](https://boards.straightdope.com/t/continuing-discussion-of-spacex-launches-edited-title/741048/1160 "2021-05-03T14:27:37Z")
I wonder if they splashed at night just to prove it can be done [Previous page](https://boards.straightdope.com/t/continuing-discussion-of-spacex-launches-edited-title/741048.md?page=57) [Next page](https://boards.straightdope.com/t/continuing-discussion-of-spacex-launches-edited-title/741048.md?page=59)