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Redjoker

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Everything posted by Redjoker

  1. It seems like it, but Sarbian did say up to 3 hours till live so hopefully it will be back up in the 40 minutes or so.
  2. @sgt_flyer @Steel That's weird, it's looks perfectly fine on my end with Win 10 and chrome.
  3. Space exploration plays a major role in the history of humankind. The cultural, political and sociological repercussions are extraordinary, and the amount of resources dedicated to space exploration is enormous. This aerospace course is a first step for those interested in learning more about the history of the space and the impact of space exploration on our daily lives. Each week we will focus on a major chapter in the history of space exploration accompanied by an introduction to the relevant technical topics to fully understand these historical developments. During the seven weeks of the course, we will follow the technical, political and cultural contexts that lead to the birth of the space age, uncover the evolution of space exploration from competition to cooperation in the Apollo and post-Apollo era and finally, analyze current trends in space exploration. By successfully completing this course, you will acquire the critical tools to understand the key events and developments of the Space Age. You will learn to solve basic technical and engineering problems of space travel, rocket propulsion, space systems, and human space flight. Course image: Rosetta at Comet (landscape) / Copyright: ESA/ATG medialab; Comet image: ESA/Rosetta/Navcam. See moreabout The Conquest of Space: Space Exploration and Rocket Science What you'll learn The history of space exploration and its cultural, political, and scientific impact Fundamentals of aerospace engineering, including how to move in space and how rockets work The key aspects of space systems and the space environment Current trends and future projects in space exploration I have no idea how op did that, but here it is with readable formatting.
  4. I think that all of you might find this map interesting/useful, it's a map of light pollution worldwide. http://darksitefinder.com/maps/world.html
  5. Actually you could use the rocket equation and solve for the final mass and subtract that from the initial mass to find out how much fuel you used. You could then divide the difference by your fuel usage. and or Delta-V = Isp g ln( Minitial / Mend ) or Mend = Minitial / e Delta-V / (Isp · g)
  6. If you need the exact burn, it gets more difficult because calculus is the only way I see of finding it. You would need a function or set of functions that models the acceleration of your rocket as it loses mass. You would then need to solve for the end time with an integral that equals the delta-v of the maneuver and starts at 0.
  7. I not completely sure what you are asking for, but are you asking for how long your burn will need to be to complete a maneuver that you know the delta-v for? If so first you need to know your acceleration, you can take you TWR and multiply it by 9.8m/s2. You can then take the delta-v for your maneuver and divide it by your acceleration to get your burn time in seconds. This won't be entirely correct since you will lose mass and increase your TWR while you burn, but it should be close enough if you aren't doing massive maneuvers or losing a large portion of your mass during your burn. TL/DR: Delta-v/(TWR*9.8m/s2)
  8. "Launch & landing can be seen on the spacex.com webcast or in person from Cape Canaveral public causeway at 8:33pm local tmr" -Elon Musk https://twitter.com/elonmusk/status/678732298532085761 That sounds like they will livestream the landing.
  9. Reaction wheels work because angular momentum has to be conserved. You start out with a space craft with nothing rotating so your momentum is zero. Since no external forces, at least in our model, are acting on it, the final momentum also has to be zero. We begin spinning up a disk inside the space craft clockwise, so that it has momentum in the clockwise direction. Since we have clockwise momentum, but our final momentum has to be zero, the rest of the craft will begin to rotate counter-clockwise. There are a couple of ways you can demonstrate this. First you will need a disk or wheel, for example from a bicycle, with an axle that you can hold on to and a chair or stool that can freely rotate. 1. Sit on the stool and keep your feet on the ground. Hold the bicycle wheel, so that the wheel is parallel with the ground have someone spin it for you as fast as possible. Lift your feet off he ground and then flip the bicycle wheel over. What happens is really cool. Here is a video, but I suggest you try it yourself: [url]https://youtu.be/UZlW1a63KZs?t=50[/url] 2. For this one you will something with a rotating wheel that you can hold while hold the bicycle wheel. Sit in the stool with your feet off the ground. Hold the bicycle wheel in one hand the the object in the other. Press the rotating object against the wheel, so that the wheel will begin to rotate. When I did this in class, we used a drill attached to what appeared to be a hole saw with it's blades ground down. This demonstrates how a reaction wheel works.
  10. [quote name='Mighty1']Oh, you have no idea how I would like do go all electric but this stupid country of mine imposes extra tax if you want anything else than gas. Even if you want lpg in your car you have to pay extra.[/QUOTE] In the US, the tax on gas is a usage tax for the roads and provides the main source of money for road repairs and construction. There is an extra tax for electric and alternative fuel vehicles because you don't buy gas and pay the tax that supports the roads you drive on.
  11. My opinions: Dragon/Spacex: Sure to win. It has completed 6 launches of the V1, so no R&D needed. Also the V2 could be used for larger payloads with no extra R&D costs, since it is funded through CCDev. CRS-7 did fail and the Falcon 9 is expected to fly again by the end of 2015 and CRS-8 in early 2016. Cygnus/OribitalATK: Has a decent chance of being selected. It has completed 3 of it's contracted missions and should resume flights on an Atlas V by the end of the year after the CRS-4 failure. CST-100/Boeing: Has a decent chance and probably a better shot than the Cygnus. It doesn't need additional R&D funding, since it is funded through CCDev. Boeing has the advantage of being a long time government contractor and the Atlas V is highly reliable. The main disadvantage is probably cost. Since it is primarily a manned capsule it will likely have a higher cost than the dragon V1 or Cygnus and only has pressurized cargo space, although that is balanced by it's highly payload capacity. Dream Chaser/Sierra Nevada: Least likely proposal. It will require funds for R&D that the others don't. It is the only applicant that doesn't have it's own LV and would be subject to the launch scheduling of another company. It does however have the advantage of the lifting body design that could be useful for transporting injured crew with lower Gs on reentry. I think that the Dragon and CST-100 will be selected, although Cygnus has a decent shot at beating the CST-100.
  12. Hope for good weather, I spent two days at a beach to watch the second to last shuttle launch, but both attempts were scrubbed.
  13. You all might find this article interesting: http://www.themoscowtimes.com/article/536827.html The article says that an official told TASS, a Russian state owned news agency, that the assembly building is too small and will not be able to stack the stages for the Soyuz 2.1a. It was apparently designed for a previous version and the building designs were never updated. If it is true, then it looks like they may not be able to launch the Soyuz from there before the end of the year.
  14. Is that a fuel tank under that heavy command module? I don't believe that you can pass crew through those tanks.I believe you should be able to pass crew through that 6-way connector, but I'm not sure about passing through what looks to be a proc structural part between the hub and fuel tank.
  15. According to Wikipedia it is done with small solid rocket motors. I usually use two separation motors to create the spin. Source: https://en.wikipedia.org/wiki/Spin-stabilisation
  16. According to this post by NathanKell it seems like 1945 is the starting date. You might be able to get a more accurate date by getting launch windows between to other planets and comparing them with real life launch windows.
  17. For those of you waiting for the update to appear on CKAN, I may have found a way to do it now. It appears that if you copy the text from this link: https://github.com/KSP-CKAN/CKAN-meta/blob/master/RP-0/RP-0-0.0.34.ckan into a text editor like notepad and change the KSP version to 1.0.4. Save the file and end the file name with .ckan. Then in CKAN hit file and install from .ckan, select your file and it should begin installing the mods and give you the recommended mod list. The only downside is that it seems to install RO version 10.2. I haven't tested the install yet, so do this at your own risk and not on your current install. Also don't forgot to install RSS since it isn't set as a required mod for RO in CKan
  18. What do you mean? I believe it shows up as a recommended mod on CKAN but, it isn't a requirement because not everyone uses RO on RSS.
  19. I' not sure if this is intentional or a bug. Certain engines like the J-2, used in the Saturn V upper stage, will present the "vapor in feed lines" message even if the fuel was stable prior to ignition if the throttle was set to 100%. Starting the engine with the throttle at 0% and then throttling up will allow the engine to work. @Tekener: Until someone with more knowledge responds on this, throttle down to 0% before igniting the J-2s in the second stage, stage to ignite the engines, and then throttle up to 100%. This seems to work for me. Edit: Had a similar issue a few days ago with the Atlas first stage, with throttle at 100% the sustainer, 2 booster engines, and 2 verniers reported "vapor in feed lines" on the launchpad, but can't get replicate the results.
  20. Your problem is Ullage. The fuel for most rockets is a liquid and under gravity it flows nicely into the engine. However without gravity it begins to float around and your engines have trouble getting fuel, result in air or "vapor in fuel lines" and shut down to prevent damage. To solve this problem there are a couple of solutions. The first is hot staging where your second stage fires while your first one is burning. The next is ullage motors which are small engines that don't require ullage and provide acceleration to force your fuel down. The final is a pressurized bladder that you fill with helium or nitrogen and expand to keep your fuel in the bottom. I'm not sure which methods the Saturn V uses, but I will post after I boot to my Linux partition and launch the Saturn V. Edit: The first stage engines shut down because you set your throttle to zero and when you raised your throttle the tried to start but couldn't due to only having one ignition. This involves two things, the first being that very few engines can throttle (SSME 69-109% and even less can deep throttle ( ex:RL10 8-104%) and secondly that engines have a limited number of ignitions. To solve the first problem, be sure to not set your throttle to zero after starting an engine and pay attention to what engines are throttable. The second problem is that he F-1 engines were never designed to be able to ignite after launch and other engines may have a limited number of restarts due to what ever allows ignition to occur being used up. However, some fuels are hypergolic the ignite on contact with each other and have unlimited restarts.
  21. Close, the red dots are ground stations for remotetech. According to this post: https://www.reddit.com/r/RealSolarSystem/comments/3d125s/how_do_i_switch_launch_sites , you need KSC switcher from here: https://kerbalstuff.com/mod/749/KSC%20Switcher to change launch sites.
  22. It the same process as a direct ascent to rendezvous except you don't match velocities and want to hit the target. To your second question, nothing is done, destroying a satellite with a missile generates a large amount of debris. The last chinesse test in 2007 resulted in roughly 2,317 pieces of debris golf ball sized or larger.
  23. I think Imaspacestation meant that if an object collision resulted in the ISS depressurizing, could the astronauts get in the Soyuz while the station had lost pressure. If they can, is the Soyuz capable of re-pressurizing after it has depressurized by the astronauts entering it.
  24. I think I may have found the problem. It seems that the BAC model 8250 engines that are on the secondary propulsion system(SPS), the Agena-D flight pack part, were used as ullage engines. According to the engineering report listed below the fuel of these engine was stored in "positive pressure expulsion tanks" in other words they used a bladder pressurized with gas (Nitrogen I believe) to eliminate the need for ullage on the SPS. The problem is that the Agena-D flight pack has ullage set to true when it should be false. Source:https://archive.org/stream/nasa_techdoc_19790077027/19790077027#page/n129/mode/1up Section 4 deals with the SPS
  25. I probably could have phrased that better. If one SRB adds enough thrust, why add another booster that will increase the cost of the rocket if you can tilt the SRB's nozzle and gimbal the RD-180 so you are still thrusting through your center of mass. Doing it this way is probably less fuel efficient than adding a second booster, but the lower cost makes it a better option.
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