Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

SpaceX lands rocket at sea second time after satellite launch

phys.org

Post reply on HN
Print view View original

241–250 of 497 posts

Re: SpaceX lands rocket at sea second time after satellite launch

#241

Post by ck2 »

taneq wrote: post #123
throwaway2016a wrote: post #118

Earlier quoted context omitted.

Slightly off topic but I was watching a television show the other day and someone said they worked at NASA. The host then said "So you're literally a rocket scientist?" And the guy said emphatically "Rocket engineer, there is a big difference" I'm sure this particular task probably was a little bit of both. After all, they had to run several real world experiments to prove their calculations.

It's important to know the difference: https://i.imgur.com/r6oEhvS.jpg?1 The most interesting work is right in the intersection of the two disciplines, though. :)

xkcd needs to make one for that too https://xkcd.com/435/

I guess "purity" is just another word for "lack of immediately applied practicality"

Re: SpaceX lands rocket at sea second time after satellite launch

#242

Post by fit2rule »

shiven wrote: post #108
brianwawok wrote: post #95

Here is the video http://www.space.com/32811-spacex-rocket-landing-jcsat-14-la... Hopefully we won't have the typical hacker news discussion about why the employees chant USA.

Yoo.Ess.Ae! Yoo.Ess.Ae! Yoo.Ess.Aeh! There. See. No harm, no foul. Anyways, as a non-American living in the US since 2001, I fail to see an issue with chanting USA, one way or another. It is an American company, with majority US employees, running this project (mainly) for an American entity (NASA), on US sovereign territory (or ocean?), using a significant chunk of US resources. So, it is their company and their cou…

I think its offensive to have nationalistic robot-like-chanting being defended as an okay thing. Its the sort of thing you expect people to do at rallies or cult gatherings, and from an outsider perspective it always tarnishes what is otherwise a very rational event, because its an implied irrational, collective mindset. As a non-American, I wish it'd stop - its a major turnoff for these events, and I switch away when it starts up.

I know, I know - Americans have a right to be proud, and they do. But expressing it with a cult-like mechanism that is, essentially "our group is great, nobody else can/has done this" is just .. revolting.

I say this, knowing full well I'm going to get down voted for it, but I really do wish you Americans would think about it from the other side of your dark mirror. Can't we come up with a chant that includes all of humanity? After all, America wouldn't be the nation it is today without all other nations on Earth, including the ones that America has invaded, and destroyed completely, wantonly, for decades.

EDIT: Feel how this post detracts from the main article, and is a distraction from the feel-goodness of SpaceX's accomplishments? For us non-Americans, thats how the USA-cult chant feels - a total distraction. I wish I could down vote the chanting when I see it on TV, too.

Re: SpaceX lands rocket at sea second time after satellite launch

#243

Post by x5n1 »

rdancer wrote: post #218
mikeash wrote: post #179

Earlier quoted context omitted.

I can't imagine how anyone with the slightest clue could conclude that the first stage would sink the barge. The scales are just too different; the barge outweighs the rocket by orders of magnitude. I hope this is one of those "lost in translation" things, because otherwise I fear for that group of supposed experts.

> the barge outweighs the rocket by orders of magnitude The energy amount the rocket impacts with is dominated by its speed, not its mass. A small, fast-travelling projectile can make a hole in just about any kind of armour. The terminal velocity is quite low, but that's in part because of the way it is engineered — an ICBM would probably be able to put a hole through a ship deck with ease. There is a lot of reasonin…

f = ma.

Re: SpaceX lands rocket at sea second time after satellite launch

#244

Post by Kinnard »

I wonder if there's coordinate potential with seasteading? Astronauts are gonna want all sorts of goods and services upon landing I imagine. Having someone stationed nearby will mean swifter pickup of equipment and astronauts. And if there's someone stationed nearby they'll want goods and services as well.

Re: SpaceX lands rocket at sea second time after satellite launch

#245

Post by jklinger410 »

sjtrny wrote: post #217
mikeash wrote: post #195

Earlier quoted context omitted.

Good ol' HN. These folks are pushing the boundaries like nobody else, advancing humanity more than a thousand Facebooks or Snapchats ever could, but if they express pride in their work it's a "circle jerk."

Well the advances remain to be seen in the decades to come. I could understand that level of excitement for putting a person on Mars but not for a satellite deployment or ISS restocking mission. Maybe it's just a cultural difference but there is something unsettling and cringey about seeing those employees act so enthusiastic. Is it genuine? Maybe for some employees. But the camera setup makes me think there is some…

>I could understand that level of excitement for putting a person on Mars but not for a satellite deployment or ISS restocking mission.

I have seen that level of excitement over a soccer match.

I think your priorities are personal, and you should maybe not project them to other human beings. Not everything is objective.

Re: SpaceX lands rocket at sea second time after satellite launch

#248

Post by lfuller »

lmm wrote: post #205
jacquesm wrote: post #117

Earlier quoted context omitted.

NASA landed a first stage on a barge to be re-used?

NASA reused every engine (not just the first stage) of an orbital payload delivery system, many times, 30 years ago. Runway rather than barge but that's not really an important difference. (The exciting part will be much cheaper refurbishment than the STS. But SpaceX haven't actually delivered on that component yet)

Technically, the full SRBs were never (to my knowledge) re-used. Because of the salt water damage, they were parted out and some of those parts were used in new engines.

Re: SpaceX lands rocket at sea second time after satellite launch

#249

Post by jklinger410 »

I find the level of criticism for SpaceX on this site to be incredible.

I understand this is a place for intelligent discussion, but sometimes I feel like I can't find a single thread on this site without someone in the comments presuming they are smarter than someone else.

Re: SpaceX lands rocket at sea second time after satellite launch

#250

Post by iandanforth »

gist wrote: post #238

The big difference between landing at sea and on land seems to be the PR value. Otherwise a target is a target, taking any differences in weather into consideration. In fact it seems that landing at sea is actually less pressure since you don't have the same safety concerns and crash pictures (which are bad for publicity) the rocket simply disappears.

This is incorrect, it's about fuel. By the time the rocket has completed first stage separation it's traveled a long way "horizontally" and is no longer near the launch site. They are trying to create a landing spot as close to the rocket as possible so it can't make it back. The only orbits that can reasonable get all the way back to land are fairly low and from specific launch sites.
Post reply on HN