# MetricKerbalist

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1. ## As liftoff proceeds, the desired inclination of your rocket equals the lattitude from which you are lifting off.

Hi @Hannu2, I don't understand the sentence that I quoted. Would you mind explaining further. Hi @K^2 Would it be burdensome for you to show this trig? I thank both of you for your posts and your consideration. Stanley
2. ## Steam

Thank you, @Geonovast. Good. That worked. As you were stating what needed to be done, it refreshed my memory. I am glad I checked this actually, because I had about 100 files that needed to be reloaded. Steam took care of it right away. Stanley

4. ## As liftoff proceeds, the desired inclination of your rocket equals the lattitude from which you are lifting off.

Hi everyone, Thank you very much. Back to the NAR rule to which I referred above, it would be better if it said that, for a high-powered rocket, "the minimum pitch" must be 70 degrees. This was all very helpful. Stanley
5. ## Argument of periapsis

Thank you, @Rhomphaia. Let me think about what you are saying. This is deep.
6. ## Argument of periapsis

Hi KSP colleagues, I would please like to follow up on this issue of the Argument of the Periapsis (Arg Pe), and introduce the issue of Longitude of the Ascending Node (LAN). I have a rocket on the launch pad at Kerbin Space Center. Its Arg Pe reads 90.0 °, no matter the time of day. When I time warp, however, the LAN keeps changing. Could someone be so kind as to explain what is going on. Thank you for your consideration. Stanley
7. ## As liftoff proceeds, the desired inclination of your rocket equals the lattitude from which you are lifting off.

Hi everyone, Actually, this discussion clarified a few things in my mind. Let me summarize, and get things nailed down. Let's say that we were at Kennedy Space Center, and let's agree to call its latitude 28 °. Case 1: A rocket is standing upright on the launchpad Inclination: 28 ° Pitch: 90 ° Heading: ? Case 2: A rocket is lying on the ground with its nose pointed towards Tallahassee Inclination: 28 ° Pitch: 0 ° Heading: 300 ° or North 60 ° West Case 3: A rocket is lying with its aft side on the ground and its nose propped up 30 ° pointed towards London Inclination: 28 ° Pitch: 30 ° Heading: 40 ° or North 40° East Case 4: A rocket is suspended vertically from its aft side and its nose pointed straight down Inclination: 28 ° Pitch: -90 ° Heading: ? Could anyone please confirm the three parameters for all four cases. Note, however, that I have a question mark regarding the heading on Case 1 and Case 4. Thank you. Stanley
8. ## As liftoff proceeds, the desired inclination of your rocket equals the lattitude from which you are lifting off.

Thank you, @Meecrob. That makes sense.
9. ## As liftoff proceeds, the desired inclination of your rocket equals the lattitude from which you are lifting off.

Hi everyone, This is interesting. I have a rocket on the launchpad right now, and I am looking at the Orbit Info Panel. The inclination reads 0.1 degrees (I don't know why it's not exactly 0.0 degrees). Moreover, the NavBall is solid blue with the orange dot centered at zero degrees. So perhaps Kerbal Space Program also considers the initial inclination to be zero degrees, and not 90 degrees. Stanley
10. ## As liftoff proceeds, the desired inclination of your rocket equals the lattitude from which you are lifting off.

Hi @cubinatorand everyone else, Thank you for your response. When the rocket sits on the launch pad, I would also like to call its inclination 90 degrees. However, I am a member of the National Association of Rocketry, and I know for a fact that the NAR calls it zero degrees. For example, NAR rules state that, for a high-powered rocket, "the maximum launch angle, measured from vertical" is 20 degrees, and I am citing Section 7 of the NAR High Power Rocket Safety Code. I myself would prefer to call it 70 degrees, and apparently so would you. All of us rocketeers need to come to some agreement on this issue, which should be easy enough to do. Using the right-hand rule -- which makes a lot of sense -- the angle would be +90 degrees, I believe. Right? The tip of your thumb would be the nose of the rocket. Stanley
11. ## As liftoff proceeds, the desired inclination of your rocket equals the lattitude from which you are lifting off.

Hi KSP colleagues, I agree with everything that RCgothic just said. When the rocket sits on the launch pad, its orbital inclination is actually 90 degrees. By convention, however, rocketeers call this zero degrees, don't they? Next, once the rocket gains some speed -- usually between about 50 m/s and 100 m/s -- you start to tip the rocket over, oh, let's say 3 degrees. Its pitch angle then should be called 87 degrees, but by convention rocketeers call this 3 degrees. Let's just define our terms. When the rocket sits on the launch pad straight up, are we going to say that the pitch angle is zero degrees or 90 degrees? Stanley
12. ## Argument of periapsis

Hi KSP colleagues, I would like clarification on something please. Wikipedia explains that the argument of periapsis is "the angle from the body's ascending node to its periapsis, measured in the direction of motion." Now we all know that Kerbin's orbital inclination equals zero degrees, and the KSP wiki notes that Kerbin's argument of periapsis also equals zero degrees. Since Kerbin's orbital inclination is zero, Kerbin does not actually have ascending or descending nodes, right? Moreover, since Kerbin's orbit is circular, it has neither a periapsis nor an apoapsis, right? Thus, only by convention -- to get a reference point -- can we speak about Kerbin's argument of periapsis. Again, isn't this correct? Thank you. Stanley
13. ## As liftoff proceeds, the desired inclination of your rocket equals the lattitude from which you are lifting off.

Hi @mikegarrison, First, I appreciate your response. I guess I don't understand this, but I am always trying to learn. Could you or someone else please be so kind as to define these three terms -- and in particular the difference among them? Thank you for your consideration. Stanley
14. ## As liftoff proceeds, the desired inclination of your rocket equals the lattitude from which you are lifting off.

Hi KSP colleagues, The guideline during liftoff of a rocket is to get your spacecraft inclined to the same degree as the complement of your latitude on the planet, and also head due East. Thus, at the Kerbin Space Center, which is on Kerbin's equator (0 degrees, of course), soon enough you want to get your rocket inclined to 90 degrees. Hypothetically, therefore, if we were lifting off at 30 degrees North latitude (or 30 degrees South latitude, for that matter), the spacecraft should get to an inclination of 30 degrees. And for one last example, if we were lifting off from Kerbin's North or South Pole -- obviously, highly less than desirable -- you would point your rocket ship straight up, and thus with zero=degrees inclination. We all understand that this method takes the most advantage of Kerbin's counterclockwise rotation. Moreover, the same principle applies on Earth, in the real world. When I first heard this, it sounded so strikingly simple that I was skeptical. But when I thought about the extreme case of a rocket's lifting off from the North or the South Pole, I realized that the guideline was true. But I would please like to see proof that it is true. Could one of you knowledgeable ISP forum readers kindly show a proof. Thank you for your consideration. Stanley
15. ## Gravity in low-Kerbin orbit (or low-Earth orbit)

Thank you everyone, in this case especially @HvP and @Beccab. That YouTube video was indeed helpful.
16. ## Gravity in low-Kerbin orbit (or low-Earth orbit)

Hi KSP colleagues, Let me please follow up on this topic. Consider the space stations that you see on science fiction like in 2001: A Space Odyssee. There we see a torus always in rotation around its own axis. People on the station walk around as though there were gravity. Would there be local gravity on the space station? If so, does the rotation make it happen? Or is this just fantasy? Thank you. Stanley
17. ## Gravity in low-Kerbin orbit (or low-Earth orbit)

First, I thank everyone for their contributions. They all helped. Second, two of the points that @mikegarrisonraised were particularly useful for me: The first point put the issue quantitatively. As you go higher in orbit, you gain potential energy, but you lose kinetic energy. Thanks again, everyone. Stanley
18. ## If the game locks up, how do I unlock it?

Hi KSP colleagues, Fortunately, I have not had any game freezing since my last communication. However, following @jimmymcgoochie's advice, I have been turning on Task Manager before starting KSP. Interestingly and unexpectedly to me, the game consumes considerable computer resources. Here are significant statistics: About 19% of CPU About 2275 MB (26%) of memory About 34% of GPU Power usage is "very high" Other than the few game freezes that I have had, KSP loads nice and quickly and it runs beautifully. That's why I was so surprised to see the substantial usage of computer resources. Of course, the game does so much that perhaps I should not be surprised. Stanley
19. ## Gravity in low-Kerbin orbit (or low-Earth orbit)

Hi @cubinator and everyone else, I did a quick check with the KSP wiki, and indeed the farther a planet's orbit from Kerbol the slower its orbital velocity. And as @mikegarrisonwrote: So, I certainly don't dispute the fact that a higher orbit leads to a slower orbital velocity. Thank you all for correcting me on that. Unfortunately, I do not yet see the logic -- "you will have less energy staying in orbit." I don't understand what that means. I am not saying that I therefore conclude that you should go faster in a higher orbit. I just don't see any cause and effect. The fact that I don't see it is my fault. But it isn't clicking yet. Stanley
20. ## Gravity in low-Kerbin orbit (or low-Earth orbit)

Hi @FleshJeb, Please. I would love to see the derivation. Thank you for your consideration. Stanley
21. ## Gravity in low-Kerbin orbit (or low-Earth orbit)

Question, please, @FleshJeb or anyone else. I am confused. I just calculated the speed necessary for a circular orbit of 95 km above Kerbin. I got the answer of 2253.8 m/s. I thought that orbital velocity should increase with altitude, not decrease.
22. ## Gravity in low-Kerbin orbit (or low-Earth orbit)

Hi @FleshJeb, I am going to print out your answer, and go through it line by line. Thanks. Stanley Oh, so that's where the 2278.5 m/s comes from.
23. ## Gravity in low-Kerbin orbit (or low-Earth orbit)

Thank you, @magnemoe. I guess that makes sense.
24. ## Gravity in low-Kerbin orbit (or low-Earth orbit)

Hi KSP colleagues, I should know the answer to this question, but I don't. Consider a real spacecraft in low-Earth orbit -- oh, perhaps 400 kilometres or whatever. Similarly, consider a spacecraft in low-Kerbin orbit -- again, perhaps 80 kilometres or whatever. The craft is well within the planet's gravitational force. Yet the astronauts or kerbonauts on board are in a state of weightlessness. How come? Thank you. Stanley
25. ## How does a rocket in orbit change its attitude without firing an engine?

Hi @Rhomphaia, Good. That's clear. Stanley
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