Shpaget

The same way you know that some of the countless military satellites already in space aren't armed. You don't know. You can only place trust, hope and silently do it yourself, just in case. Anyway, without a very accurate trajectory prediction over long periods, there is little hope we can do anything. To achieve such accurate predictions, we need space based telescopes, and not just in LEO, but in solar orbit, and preferably inclined.

If an asteroid the size of the Tunguska one hit the central Europe, Eastern US, India, Japan or any densely populated area there would be a lot more going on than a few broken windows. Searching and tracking requires large budgets too and if you don't constantly look out for potential impactors don't be surprised when one does hit.

A light year is quite an arbitrary unit, cosmologically speaking. Once you round up/down by up to 0.4 ly, it gets even less meaningful. Also, inside those 17 ly, how many planets are there that are not habitable? Furthermore, numerology is poo.

And when they do mature, they'll be used on multistage rockets as well and further improve them, setting the bar for SSTO even higher.

So, we're already overdue? Tunguska 1908. As for the original question, it can take quite a bit, depending on how you define "ready enough". The capability to redirect 100 m rock with 20 years of advance warning is quite different from redirecting a 10 km rock with 2 years warning. Then again Chelyabinsk roid was unknown until it smacked us.

Wasn't it proven that, using same propellant and structural materials, SSTO will always be less efficient than a multistage rocket?

They use supersaturated sodium acetate solution that when triggered with the metal disk starts to crystallize. The crystallization releases the heat introduced by "cooking" it.

The quote is: Leia: Luke, what's wrong? Luke: Leia, do you remember your mother? Your real mother? Leia: Just a little bit. She died when I was very young. Luke: What do you remember? Leia: Just images, really. Feelings. Luke: Tell me. Leia: [sigh] She was very beautiful, kind but sad. Why are you asking me this? Luke: I have no memory of my mother. I never knew her. ... bla bla bla... back and forth Luke: The Force is strong with my family. My father has it. I have it. And my sister has it. Yes, it's you Leia. Leia: I know. Somehow I've always known.

No. They get pushed a lot later than seeing you pushing them. The "push" travels at the speed of a longitudinal wave through whatever material the stick is made of.

Guys, your explanations are not relevant. Laser dot on the moon is not a physical object and such a dot can move faster than c. There is no matter or information that is traveling faster than c. Speed of sound through the rod explanation is also not applicable since OP is not talking about acceleration, but the final speed. So what if it takes a while for the end of the stick to accelerate? The question is, can the end of the stick break the speed limit of c? While the answer is still a "no", it is because of a different reason. Even if your stick is very strong (but still flexible) and angular acceleration is low enough to not cause the break in the stick, the end of the stick will still never surpass c because as any mass approaches c, its mass increases and approaches infinity, so it would take an infinite torque to swing a stick and break the c barrier.

It wouldn't be the first retcon Lucas did. My vision is to have Neeson cut up little Anakin and leave the annoying Jar Jar in the dessert to keep the even more obnoxious C-3PO some company. They would be much better characters if they just stopped appaering altogeter after Tatooine.

There would not be the same mass. There would be 26 t less hydrogen, so if those engines ran at stoichiometric and managed to burn 100% the exhaust temperature would be higher than with rich mixture. Would the mass reduction and increased temp be enough to offset lack of H2 in exhaust, I don't know, but as I said earlier, are we sure the main reason to run rich is the ISP boost and not avoidance of oxidizing flame? I don't honestly know, I haven't done the math.

in just 5 years of preparation? I don't think so.

I know this is an old post, but since the thread has already been resurrected... The latests design of the external tank of the Space Shuttle carried roughly 630 t of LOX and 105 t of LH2, so it's the other way around. LH2/LOX ratio being burned is 0.167. There is 6 times more oxygen (mass) than hydrogen, instead of 8 time it would be required for stoichiometric mixture, so only 26 t out of 105 t of hydrogen is not burned. The main reason for the rich mixture, I would assume, is to avoid having an oxidizing flame, which would be a problem for engines that are supposed to be reusable. Higher ISP is a side bonus. Edit: Oh, I forgot to say that, in this case, higher ISP doesn't necessarily mean higher dV. I haven't done the math, but if throwing out unreacted fuel was a good idea, they'd just open a valve at the bottom of a LH2 tank.

What bothers me more is if Yoda and all his pals, including Liam Neeson, anticipated Anakin to "bring balance to the Force" why didn't they light sabered him in tiny little bits as soon as they saw him? At that point Jedi (light side) had a monopoly on the force and ruled the galaxy. "Balance" can only mean the rise of the dark side/extinction of the Jedi.

I really need to speed up my project to motorize the focus ring on the 800mm mirror lens.

Trajectory of something in the air greatly depends on its aerodynamics so it's pointless to even consider air resistance in a general case. That being said, ballistic trajectory is eliptical. Parabolic trajectory implies escape velocity. Shell theorem states that shell and sphere shaped masses can be replaced by point masses. https://en.m.wikipedia.org/wiki/Shell_theorem

No, this is somewhat different. Tank has it easy. As you can see, given the situation, my request to record only three screens is rather simplistic. The three screens I'm interested are in the bottom row, third and fourth from the right and the one above them. The one above them is actually only a bonus. If all else fails, I can do without the image from it and will be happy-ish with just the bottom two.

I'd like to record the screens on a PC since a program I'm running acts up a bit every once in a while (sometimes entire day goes by without a hitch, sometimes I get two problem in an hour and then nothing for a week). The thing is, the program takes up 3 1920 x 1080 monitors and there are a bunch of tiny numbers all around, which I'd like to be able to see in the recording. Good news is that I only need about 5-10 minutes worth of footage to satisfy my needs. The bad news is I don't know when the problem is about to occur, so I'd like to record continuously. Since I would not like to burden the PC with any unnecessary tasks such as compression on the fly, my thinking was to have the screen recorder overwrite old footage as to not consume insane amount of storage. Is there a screen recorder that can record 3840 x 2160 desktop (there are two monitors in the bottom row and one on top of them) and loop through the recording?

What if they had all the tech we consider modern and advanced and decided to "go back to roots" long before "western" civilization?

That's either an amazing amount of wear or a really crappy paint job.

Thank you.

Mostly I miss the stuff covered by KER. I find numerical readouts of various values very important. I'd also like to see easier fuel lines between ships. Docking is nice, but transferring stuff between two landed craft is virtually impossible and highly impractical, even when using two ships designed for such operations. I'd like to have proper 6 axis of freedom on EVA. Sometimes it's impossible to get back into a ship because the hatch is "up" and the Kerbal can't be pitched up or down practically.

I started playing in June, joined the forum in September 2012 and survived the Great Wipe. What has kept me playing? Well, these days, I play only ocasionally, but I always look forward to a new version and I like to check out new features. I like the way the game developed, but I still miss some very basic features

That's a beautiful design, but the part clipping bothers me a bit. Care to share the craft file? I'd love to take it apart and examine in detail.