# The Great Ongoing Space Exploration Thread **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Tags:** science-math\ **Created:** [November 16, 2020, 12:18pm UTC](https://boards.straightdope.com/t/the-great-ongoing-space-exploration-thread/925703 "2020-11-16T12:18:17Z")\ **Posts on this page:** 20\ **Page:** 73
**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:** [July 17, 2024, 10:06am UTC](https://boards.straightdope.com/t/the-great-ongoing-space-exploration-thread/925703/1442 "2024-07-17T10:06:56Z")
ISTM the big question there is how big and how many are the chunks that might reasonably reach the surface? Which of course is a function of apogee, vehicle geometry, etc. Plus whether the failure to relight results in no fire at all, or major explodiness, The few Dragon parts that have landed intact suggests that maybe big chunks are a possibility. ---
**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:** [July 17, 2024, 10:21pm UTC](https://boards.straightdope.com/t/the-great-ongoing-space-exploration-thread/925703/1443 "2024-07-17T22:21:30Z")
> [@Dr.Strangelove](#): > > I still lean toward the plain Dragon, though. There’s enough room in the trunk for the propellant. Not quite what I was expecting. Not a Dragon XL, but pretty far off from a stock Dragon: > > > NASA @NASA No SuperDracos. Extended trunk–looks to be about 2x the length. And zillions of engines on the end, which I expect are Dracos with extended nozzles. I guess they wanted better throttling and lower cosine losses. ---
**Author:** ![Lumpy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lumpy/32/446_2.png) [@Lumpy](https://boards.straightdope.com/u/Lumpy)\ **Post date:** [July 17, 2024, 10:45pm UTC](https://boards.straightdope.com/t/the-great-ongoing-space-exploration-thread/925703/1444 "2024-07-17T22:45:38Z")
Cosine losses? Why wouldn’t the nozzles point straight back in the first place? ---
**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:** [July 17, 2024, 10:49pm UTC](https://boards.straightdope.com/t/the-great-ongoing-space-exploration-thread/925703/1445 "2024-07-17T22:49:36Z")
I initially speculated that they’d just use the existing SuperDracos on a Crew Dragon to reduce development effort. But those point outward by a fair amount: [![](https://cdn.geekwire.com/wp-content/uploads/2016/01/160122-dragon2-630x489.jpg) ](https://cdn.geekwire.com/wp-content/uploads/2016/01/160122-dragon2-630x489.jpg) They also have relatively small nozzles for their level of thrust. ---
**Author:** ![squeegee](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/squeegee/32/14537_2.png) [@squeegee](https://boards.straightdope.com/u/squeegee)\ **Post date:** [July 17, 2024, 10:54pm UTC](https://boards.straightdope.com/t/the-great-ongoing-space-exploration-thread/925703/1446 "2024-07-17T22:54:45Z")
When did Command Modules start getting called “trunks”? If there’s a tower escape system, is that a “frunk”? ---
**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:** [July 17, 2024, 11:10pm UTC](https://boards.straightdope.com/t/the-great-ongoing-space-exploration-thread/925703/1447 "2024-07-17T23:10:36Z")
It’s just SpaceX terminology. A LES tower wouldn’t be a frunk unless you could put something in it 🙂 . The trunk on Dragon is usually filled with cargo that doesn’t need to be pressurized. Stuff that gets fitted to the outside of the space station, like their new roll-up solar panels. It has some other purposes as well, like providing surface area for the solar panels, but it isn’t filled with the usual service module equipment. ---
**Author:** ![Johnny\_L.A](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johnny_l.a/32/1084_2.png) [@Johnny\_L.A](https://boards.straightdope.com/u/Johnny_L.A)\ **Post date:** [July 20, 2024, 1:34pm UTC](https://boards.straightdope.com/t/the-great-ongoing-space-exploration-thread/925703/1448 "2024-07-20T13:34:50Z")
**Happy Moon Landing Day** ---
**Author:** ![Elendil\_s\_Heir](https://avatars.discourse-cdn.com/v4/letter/e/7cd45c/32.png) [@Elendil\_s\_Heir](https://boards.straightdope.com/u/Elendil_s_Heir)\ **Post date:** [July 21, 2024, 3:23am UTC](https://boards.straightdope.com/t/the-great-ongoing-space-exploration-thread/925703/1449 "2024-07-21T03:23:07Z")
Huzzah for the brave astronauts of Apollo 11! ---
**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:** [July 21, 2024, 11:25pm UTC](https://boards.straightdope.com/t/the-great-ongoing-space-exploration-thread/925703/1450 "2024-07-21T23:25:11Z")
Not exactly space news, but NASA apparently considers the [a] to be canonical, even though it didn’t seem to be there: [![Imgur](https://i.imgur.com/1sJqmXa.png "imgur.com") ](https://imgur.com/1sJqmXa) It’s probably for the best if we all just pretend that he said it. ---
**Author:** ![squeegee](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/squeegee/32/14537_2.png) [@squeegee](https://boards.straightdope.com/u/squeegee)\ **Post date:** [July 21, 2024, 11:28pm UTC](https://boards.straightdope.com/t/the-great-ongoing-space-exploration-thread/925703/1451 "2024-07-21T23:28:40Z")
[The Master Speaks](https://www.straightdope.com/21341995/did-astronaut-neil-armstrong-muff-his-historic-one-small-step-line), 34 years ago! ---
**Author:** ![Elendil\_s\_Heir](https://avatars.discourse-cdn.com/v4/letter/e/7cd45c/32.png) [@Elendil\_s\_Heir](https://boards.straightdope.com/u/Elendil_s_Heir)\ **Post date:** [July 22, 2024, 2:58am UTC](https://boards.straightdope.com/t/the-great-ongoing-space-exploration-thread/925703/1452 "2024-07-22T02:58:11Z")
Momentary radio dropouts of sound were not unknown during the Apollo missions. I’m prepared to believe that Armstrong said what he meant to say. ---
**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:** [July 22, 2024, 12:25pm UTC](https://boards.straightdope.com/t/the-great-ongoing-space-exploration-thread/925703/1453 "2024-07-22T12:25:22Z")
Between momentary radio dropouts and the vagaries of sound activated microphones in the bad old days of analog electronics, I could easily see the radio unkeying during a breath, then the first syllable of the next phrase is lost because the sound activation feature didn’t “hear” it, or took enough milliseconds to key the mike that it was never transmitted. Back when we had voice-activated intercoms in airplanes it was common to learn to preface every utterance with “Uhhh” solely to key the mike, followed by whatever you really wanted to say. ---
**Author:** ![JRDelirious](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jrdelirious/32/9531_2.png) [@JRDelirious](https://boards.straightdope.com/u/JRDelirious)\ **Post date:** [July 22, 2024, 1:00pm UTC](https://boards.straightdope.com/t/the-great-ongoing-space-exploration-thread/925703/1454 "2024-07-22T13:00:52Z")
Plus hey, give the man a break, this is not what you’d call a low-stress environment. 55 years and Og knows when/if it will be tried again… sure, it was a geopolitical Cold War flex — but you know what? This is the sort of flex one respects. > [@LSLGuy](#): > > Back when we had voice-activated intercoms in airplanes it was common to learn to preface every utterance with “Uhhh” solely to key the mike, followed by whatever you really wanted to say. So I was right all along, _that_’s where that came from. ---
**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:** [July 22, 2024, 11:06pm UTC](https://boards.straightdope.com/t/the-great-ongoing-space-exploration-thread/925703/1455 "2024-07-22T23:06:22Z")
> [@JRDelirious](#): > > So I was right all along, _that_’s where that came from. Dang, I thought that was one of those linguistic accommodation things like vocal fry or high rising terminal (Valley Girl speak). And maybe it is, but it’s interesting that it has practical utility as well. ---
**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:** [July 25, 2024, 10:41pm UTC](https://boards.straightdope.com/t/the-great-ongoing-space-exploration-thread/925703/1456 "2024-07-25T22:41:58Z")
> [@Dr.Strangelove](#): > > SpaceX is asking the FAA for an early return to flight Pretty quick: > **[SpaceX](https://www.spacex.com/updates/#falcon-9-returns-to-flight)** > > SpaceX designs, manufactures and launches advanced rockets and spacecraft. > SpaceX submitted its mishap report to the Federal Aviation Administration (FAA) regarding [**Falcon 9’s launch anomaly on July 11, 2024**](https://www.spacex.com/launches/mission/?missionId=sl-9-3). SpaceX’s investigation team, with oversight from the FAA, was able to identify the most probable cause of the mishap and associated corrective actions to ensure the success of future missions. > > Post-flight data reviews confirmed Falcon 9’s first stage booster performed nominally through ascent, stage separation, and a successful droneship landing. During the first burn of Falcon 9’s second stage engine, a liquid oxygen leak developed within the insulation around the upper stage engine. **The cause of the leak was identified as a crack in a sense line for a pressure sensor attached to the vehicle’s oxygen system. This line cracked due to fatigue caused by high loading from engine vibration and looseness in the clamp that normally constrains the line.** Despite the leak, the second stage engine continued to operate through the duration of its first burn, and completed its engine shutdown, where it entered the coast phase of the mission in the intended elliptical parking orbit. > > A second burn of the upper stage engine was planned to circularize the orbit ahead of satellite deployment. **However, the liquid oxygen leak on the upper stage led to the excessive cooling of engine components, most importantly those associated with delivery of ignition fluid to the engine. As a result, the engine experienced a hard start rather than a controlled burn** , which damaged the engine hardware and caused the upper stage to subsequently lose attitude control. Even so, the second stage continued to operate as designed, deploying the Starlink satellites and successfully completing stage passivation, a process of venting down stored energy on the stage, which occurs at the conclusion of every Falcon mission. > > Following deployment, the Starlink team made contact with 10 of the satellites to send early burn commands in an attempt to raise their altitude. Unfortunately, the satellites were in an enormously high-drag environment with a very low perigee of only 135 km above the Earth. As a result, all 20 Starlink satellites from this launch re-entered the Earth’s atmosphere. By design, Starlink satellites fully demise upon reentry, posing no threat to public safety. To-date, no debris has been reported after the successful deorbit of Starlink satellites. > > SpaceX engineering teams have performed a comprehensive and thorough review of all SpaceX vehicles and ground systems to ensure we are putting our best foot forward as we return to flight. **For near term Falcon launches, the failed sense line and sensor on the second stage engine will be removed.** The sensor is not used by the flight safety system and can be covered by alternate sensors already present on the engine. The design change has been tested at SpaceX’s rocket development facility in McGregor, Texas, with enhanced qualification analysis and oversight by the FAA and involvement from the SpaceX investigation team. An additional qualification review, inspection, and scrub of all sense lines and clamps on the active booster fleet led to a proactive replacement in select locations. > > Safety and reliability are at the core of SpaceX’s operations. It would not have been possible to achieve our current cadence without this focus, and thanks to the pace we’ve been able to launch, we’re able to gather unprecedented levels of flight data and are poised to rapidly return to flight, safely and with increased reliability. Our missions are of critical importance – safely carrying astronauts, customer payloads, and thousands of Starlink satellites to orbit – and they rely on the Falcon family of rockets being one of the most reliable in the world. We thank the FAA and our customers for their ongoing work and support. Damn sensors! This one wasn’t even necessary. They failed to abide by Musk’s “the best part is no part.” ---
**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:** [July 28, 2024, 8:54pm UTC](https://boards.straightdope.com/t/the-great-ongoing-space-exploration-thread/925703/1457 "2024-07-28T20:54:31Z")
Here’s an interesting tidbit @John_DiFool found & posted elsewhere: > [@What are UFOs if they're NOT alien spacecraft?](https://boards.straightdope.com/t/what-are-ufos-if-theyre-not-alien-spacecraft/998108/166): > > Quasi-off-topic, but so far nobody has bothered to start a new thread here, which surprises me. Anyway, Perseverance found a weird rock on Mars which appears to contain similar features to Terran rocks which once were part of a floodplain: ---
**Author:** ![Darren\_Garrison](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darren_garrison/32/92_2.png) [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)\ **Post date:** [August 1, 2024, 5:28am UTC](https://boards.straightdope.com/t/the-great-ongoing-space-exploration-thread/925703/1458 "2024-08-01T05:28:26Z")
A cool view of some space junk: > **[Spacecraft travels to metal object orbiting Earth, snaps stunning views](https://mashable.com/article/space-junk-rocket-debris-footage)** > > "We're watching you from every angle." ---
**Author:** ![Mops](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mops/32/16494_2.png) [@Mops](https://boards.straightdope.com/u/Mops)\ **Post date:** [August 1, 2024, 7:24am UTC](https://boards.straightdope.com/t/the-great-ongoing-space-exploration-thread/925703/1459 "2024-08-01T07:24:32Z")
If I read the article right JAXA funds a commercial company for work in removing orbiting debris in the framework of a JAXA _demonstration_ project. Otherwise nobody would be incentivised to do this. Is there a general legal/financial framework in development, for financing deorbiting of debris by commercial companies? Do the parties that originally sent these objects into orbit have any legal obligation to contribute to deorbiting them? ---
**Author:** ![PastTense](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pasttense/32/14550_2.png) [@PastTense](https://boards.straightdope.com/u/PastTense)\ **Post date:** [August 2, 2024, 2:48am UTC](https://boards.straightdope.com/t/the-great-ongoing-space-exploration-thread/925703/1460 "2024-08-02T02:48:59Z")
Although not decided yet there is an increasing possibility Butch and Suni return on a Crew Dragon: > **[NASA says it is “evaluating all options” for the safe return of Starliner crew](https://arstechnica.com/space/2024/08/yes-nasa-really-could-bring-starliners-astronauts-back-on-crew-dragon/)** > > SpaceX is actively working on a plan to fly Starliner's crew home. ---
**Author:** ![Elendil\_s\_Heir](https://avatars.discourse-cdn.com/v4/letter/e/7cd45c/32.png) [@Elendil\_s\_Heir](https://boards.straightdope.com/u/Elendil_s_Heir)\ **Post date:** [August 2, 2024, 7:11pm UTC](https://boards.straightdope.com/t/the-great-ongoing-space-exploration-thread/925703/1461 "2024-08-02T19:11:10Z")
I get a little more worried, the more time passes and NASA still doesn’t seem to be able to decide. [Previous page](https://boards.straightdope.com/t/the-great-ongoing-space-exploration-thread/925703.md?page=72) [Next page](https://boards.straightdope.com/t/the-great-ongoing-space-exploration-thread/925703.md?page=74)