The thread for space cadets!

They actually are tested for the frequencies they would expect in a launch. Part of vibrational testing is to find what frequencies they respond at; this is why you hit it with things like a sine sweep, which is just show you where it resonates. If you only test for the frequencies you think it will respond at then that is a bad test. So first you find where it responds (which will cover launch frequencies along with a bunch of others) and then you hammer away at the specific frequencies you care about (which may or may not overlap with launch vehicle frequencies).

If they needed to retest for a specific subset of frequencies for launch compatibility then they would. Also, it's worth pointing out that launch service providers can tell you exactly which frequencies the rocket puts out and where it resonates itself. If your object does not also resonate at those frequencies then the problems you could face go way down - and this is often the case.

Given how much mass the FH can throw up, that leaves a lot of margin to go in and add/remove material and support in the car to dampen troublesome responses.

Just to reiterate - none of this is trivial but none of it is particularly challenging for major car and rocket manufacturers.
 
New Zealand is about to launch their first rocket in space. Rocket Lab was set to launch today at 2:30 PM NZDT (12/8) but the attempt was scrubbed for weather.

They try again tomorrow at 2:30 PM NZDT, 8:30 PM ET and they will begin streaming 15 minutes before the launch here. Following them on Twitter will be the best way to get live updates on the launch. The window is four hours long as well so it's hard to pin down a lift off time.
 
Airplane discussions are also welcome.
How much influence can wind have on the progress a Zeppelin or similar aircraft can make?
 
wouldn't that be the same as on a small plane , that a 10 knot adverse wind take 10 knots from the speed , no matter what the size ?
 
How much influence can wind have on the progress a Zeppelin or similar aircraft can make?
A lot. And yes, this applies to planes of all sizes too. Note that major wind and geography effects (long distance planes fly a path called a great circle route rather than a straight line because the Earth is round) are already factored into the flight time printed on your tickets. So it's unlikely that a plane would get airborne and then find out that it is going to take longer because of wind direction; they already know what the wind-delay will be and factor it into the flight time.

Have you ever noticed that a round trip on a plane can have very different flight times for the outbound and return journeys even if the trips are the same distance? That is usually due to differences in wind direction.

For very long trips I believe the differences can add up to over an hour; usually for shorter distances the difference can be a larger portion of the overall trip because on short trips the plane spends more time (as a proportion of the total journey) climbing and diving at less than full speed so adverse winds have a proportionally bigger flight time difference.
 
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On trans-continental flights the jetstream plays an important role. It's a bit like cycling with and aganist the Wind - just faster. 100km/h windspeed will result in a difference of up to 200 km/h for the different directions.
The sensitivity of airships for sidewinds is one of the reasons why the airplanes were superior to them and is still an unresolved issue for them.
 
Mmmkay, thanks!

Basically I've written a bit about a zeppelin arriving late at its destination and I wrote in ‘headwinds’ as the cause (it was a late-night writing session), and my relatively small knowledge of physics more or less told me I was right. But I felt the need to ask.
 
Rocket Lab aborted their launch at T-0 yesterday. Haven't heard anything since then.


Trump signed and executive order directing NASA to send astronauts to the moon. The order did not offer any direction nor did it provide funding. I'm sure this will go over as well as the last moon effort...nothing will happen, NASA will publish some slick powerpoint slides and then the program (if you can call it that) will be shut down to pay for a hike in military spending and tax cuts.

That's literally what happened to the Constellation program (a moon mission) 10 years ago.
 
Trump signed and executive order directing NASA to send astronauts to the moon.

I actually really enjoyed that executive order, because it gave me an excuse to throw on "Whitey on the Moon" by Gil Scott-Heron.

A rat done bit my sister Nell
With whitey on the moon
Her face and arms began to swell
And whitey's on the moon
I can't pay no doctor bills
But whitey's on the moon
Ten years from now I'll be payin' still
While whitey's on the moon
 
Rocket Lab aborted their launch at T-0 yesterday. Haven't heard anything since then.


Trump signed and executive order directing NASA to send astronauts to the moon. The order did not offer any direction nor did it provide funding. I'm sure this will go over as well as the last moon effort...nothing will happen, NASA will publish some slick powerpoint slides and then the program (if you can call it that) will be shut down to pay for a hike in military spending and tax cuts.

That's literally what happened to the Constellation program (a moon mission) 10 years ago.
Who knew Moon landings would be so complicated?:dunno:
 
BBC said:
A project searching for intelligent life in the cosmos is going to check the first known interstellar asteroid for signs of alien technology.

An initiative backed by billionaire Yuri Milner will use a radio telescope to listen for signals from it.

The team's efforts will begin on Wednesday, with astronomers observing the asteroid, which is currently speeding away from our Solar System, across four different radio frequency bands.
http://www.bbc.com/news/science-environment-42329244
 
Trump signed and executive order directing NASA to send astronauts to the moon. The order did not offer any direction nor did it provide funding. I'm sure this will go over as well as the last moon effort...nothing will happen, NASA will publish some slick powerpoint slides and then the program (if you can call it that) will be shut down to pay for a hike in military spending and tax cuts.

What do you think will be the effective impact of that executive order? I imagine that at any time you can find someone within NASA drawing up plans to go to the moon. Will this mean that there will be more people making those plans? Or will the effect of the order just be that more of these plans get submitted for ultimately rejected funding requests?
 
What do you think will be the effective impact of that executive order? I imagine that at any time you can find someone within NASA drawing up plans to go to the moon. Will this mean that there will be more people making those plans? Or will the effect of the order just be that more of these plans get submitted for ultimately rejected funding requests?
This edict authorizes NASA to spend money on going back to the moon but does not provide any funds to do so. This is the exact same situation that ARM (asteroid retrieval mission) operated on.

The net effect will be that NASA will move some money out of the various accounts used to fund ARM white papers and they will now do white papers on lunar landing.

Nothing more than paper writing will be done until Congress actually authorizes funding for hardware. It is unlikely that Congress will cut over a trillion dollars in revenue, continue increasing military budgets and increase NASA funding to a level that manned lunar flights require.

to;Dr:
Papers will be published and that's it.

Is that enough for you, uppi?
:lol:
 
But hey we got a slick NASA-sponsored Kerbal Space Program mod out of ARM so I guess the "do nothing" route has merits after all.
 
you people are so thankless . Don't you just like him filling an entire A4 page with his name ? While my signature is like limited to my surname and you will never find any two that look the same .
 
News Round Up
The Russians launched a rocket from their new cosmodrome for only the second time and it wound up in the ocean. This continues the long string of Russian launch failures going back 15+ years. I've said it before but I'll say it again, Russian quality control and mission assurance in their aerospace industry has taken a nose dive since the fall of the USSR. Nationalization of their space industry was supposed to have fixed this but it seems like the only thing it did was accelerate the plundering of this industry by wealthy autocrats.
Investigation found the reason was a programming error.
The "Frigate" booster incorrectly determined rotation direction and was unable to complete orientation maneuver in time. In Baikonur the problem never occurred because the orientation angle was different.
So it seems the source of problem was lack of integration testing. At least this time the mistake wasn't as stupid as before.
 
I don't mean to kick a dead horse but that is actually a stupid mistake to make. At least it is easily fixable.
 
Am i the only one who thinks that Oumuamua is an advanced scout for a Yuuzhan Vong Fleet coming to conquer earth?:scared:
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