SpaceX Iridium-3 Mission Launching Streaming | Hacker News Reader

SpaceX Iridium-3 Mission Launching Streaming

youtube.com

103 pointsopenmaze23 comments

The first time SpaceX landed a booster we had 1284 upvotes 432 comments (https://news.ycombinator.com/item?id=10774865), in less than two years it has become so routine that this submission has just 22 point and 4 comments.

Makes me wonder if one-day lunches to Mars and intra-planetary travel via BFR will also become so routine :)

Trips to Mars have a launch window every two years, so the inter-planatary BFR launches will remain a BFD indefinitely. :)

Edit: citation http://athena.cornell.edu/mars_facts/sb_launch_window.html

This depends largely on advances in propulsion. It's convenient to launch to mars every 2 years from a fuel efficiency standpoint, but there is no reason why we can't go there at any other time, other than current propulsion limits. At a constant 1G acceleration (including a flip over at the halfway mark for equal 1G deceleration), even at its farthest distance from earth, we could reach it in under 5 days. You even get artificial gravity as a bonus.

https://en.wikipedia.org/wiki/Space_travel_using_constant_ac...

Only problem is, 1G acceleration for 5 days straight is pure fiction at this point.

Overall, this is a good thing. What's bad is that the next time a rocket doesn't make the landing (or worse, cannot submit the payload), this will be all over the news as a failure. At least in Germany, a failure would get a mention on the frontpage of tagesschau.de (portal of the state-sponsored media channel), while a success doesn't.

If Lufthansa crashes a plane tomorrow in Berlin that'll also make the German news, while them flying hundreds of flights a day doesn't make it because it's not noteworthy.

It's the news because it's notable or out of the ordinary.

> It's the news because it's notable or out of the ordinary.

While that may once have been true, what consists of "news" today is simply whatever will grab people's attention. It's all about ratings.

It certainly does not have to be notable or out of the ordinary.

Well, the thread also started at 5:30 am California time!

Stage 1 Landing: https://youtu.be/SB4N4xF2B2w?t=1749

Already landed. I was worried the engine would not cut off ( took > 10 seconds ).

Is it possibly intentional? Eg maybe they started burning at idle thrust after landing, to empty out the tanks instead of just venting them?

I am not a rocket scientist ( IANARS ? )

There's no "idle thrust" on Falcon 9 since even the lowest thrust is enough to lift the almost empty booster. You also don't want to completely run out of fuel because your engine will probably explode. This was just a residual fire.

> You also don't want to completely run out of fuel because your engine will probably explode.

Can anyone suggest keywords/links about this? Sounds interesting.

One problem here would probably be turbopumps [1] running dry. These things run very close to their limits when fully stressed and would presumably run higher still if they no longer needed to pressurize anything.

The fuel is also used as a coolant [2] so you would not want to run out of fuel in the plumbing before you run out of propellants in the combustion chamber.

[1] https://en.wikipedia.org/wiki/Turbopump

[2] https://en.wikipedia.org/wiki/Merlin_(rocket_engine_family) (search "regeneratively cooled")

Video recorded at night. Probably normal residual burn, normally not noticeable in bright sunlight.

Fill soundtrack is pretty listenable... anyone know who's it is?

The artist they normally use for their webcasts is "TEST SHOT STARFISH".

http://www.spacexfm.com/ is a good site.

And "view-source" for an extensive list of tracks.

I read somewhere the new Iridium sats have less reflective antennas so we will probably miss the majestic flares that we see in sky.

http://www.skyandtelescope.com/observing/get-your-iridium-fi...

""" "I have been photographing Iridium flares since 1997 from various parts of the world. In fact, I was the one who first discovered the source of the flares after working with engineers at Motorola that year. I have gone so far as making a bar bet with people, advertising Iridium flares at international aerospace conferences, and emailing predictions to other overseas before there were web pages that allowed easy access to flare times." — Paul Maley, NASA Johnson Space Center Astronomical Society

Sadly, that era will soon draw to a close. On January 14th, SpaceX’s Falcon 9 delivered the first 10 of a new generation of Iridium NEXT satellites to low-Earth orbit, starting the process to replace the older units in a maneuver called slot-swapping. While the new birds will provide faster data rates and enhanced global communications, their antenna design is completely different and not expected to produce significant flares. """

My heart beat like crazy right before the landing of the first stage, always a thrill to watch.

Reply on news.ycombinator.com