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More compute power is good. The stuff I can do on my PC today in minutes would have bogged down the time-share minicomputers of yesterday for hours, to the point where the other users would have complained. I am, however, somewhat in agreement that we've mainly prettied up the interface. For...

Well if you're comfortable with some math, http://www.willbell.com/math/mc7.htm has a (brief) chapter on the Moon's motion. They didn't include the CDs back when I bought my copy. Danby can be a little terse - by which I mean, I sometimes feel like I would have liked a little more explanation...

No, he doesn't, but some other authors do. I don't think their simplified derivations would give you any kind of reasonable approximation of reality. The definitive semi-analytical work on lunar theory is: https://books.google.com/books?id=CKvQAAAAMAAJ Good luck with it. He worked on it all of...

Well... that didn't quite format right, but you get the idea. The first number is for lunar perigee, the second for lunar ascending node.

Mean annual motion of the: perigee node caused by: Principal solar action +146426.92 -69672.04 Figure of the Earth +6.41 -6.00 Direct planetary action +2.69 -1.42 from Roy...

Ha... I actually used to use TECO and had to key in the bootstrap with the front panel switches a couple of times... we used to write character-cell computer games for the VT52's. Slightly more complicated than Pong, but only slightly.

Yup. They used to play the Star Spangled Banner, or something, over a waving flag. Or was that when they came back on in the morning? ... it was a long time ago...

Well, I've seen it. I liked the older, wiser, mellower, more care-worn Han and Leia. That meshed with the old series very well. The bigger, better "death star" was interesting just for its vastness, but it's the 3rd one now. "Anakin" number two... I suppose it does play well that these young...

Not unlike the oft-asked question, "How far can you see with your telescope?" "Well, I've seen 3C273..."

Vastly superior alien life shepherding the development of the human race.

Today I learned that the Higgins Armory Museum closed a couple of years ago! Probably the coolest museum I have ever had the pleasure of wandering through... http://www.higgins.org/...

Several books here would probably help you. http://www.willbell.com/math/index.htm None of it is terribly difficult to understand, but it takes a while to get your head into that mode of thinking.

I'd say the answer to your question is "yes", but I think you're looking for more than that. Maybe you should elaborate.

Or maybe with "Ladle rat rotten hut".

Yup. The skill is called "flat filing". About 100 years ago, one was required to have the skill to make machine parts by hand if no other means were available. One of the steps, for iron parts, was to first anneal the metal, that is, to heat treat it until it softened up some, to make it easier...

Reviving an old thread... 2001 the book was awesome. The Discovery's final destination is Saturn, not Jupiter, in particular the moon Iapetus. Seems Iapetus is bi-color - very bright on one side, very dark on the other. This is true - Iapetus does indeed have a large, bright spot on it. In the...

You have to figure the positions of all the planets in their orbits. The Sun is on the opposite side of the center of mass for each. Then you add them all up. Not terribly difficult, but non-trivial. That's the numerical way to do it. Analytically, I don't know. You could assume circular orbits...

None given. He discusses fear in general, fear of the dark in particular, and how it affects astronomy - we (humans) want to light up the dark. After the above statement, he does go on to say that he sympathizes, "The stars are utterly alien, completely and forever beyond our control." I've...

"At a deeper level, I've had several people tell me that the stars scare them." -Tony Flanders, Sky & Telescope, Jan. 2016 issue

The scientist does not study nature because it is useful to do so. He studies it because he takes pleasure in it, and he takes pleasure in it because it is beautiful. If nature were not beautiful it would not be worth knowing, and life would not be worth living. I am not speaking, of course, of...

6 dB, as far as I know, is just a sort of standard value used for attenuators and hybrid combiners. It's enough to squash any reactive-ness in the load. Like some of the above posts said, you don't want your equipment feeding into reactive loads - you will generate all kinds of distortion, and...

Simple IR motion detectors are the way to go. Wiring up all your doors and windows is a pain.

"Hyperbolic excess velocity" is what you're looking for here.

You'll also need some kind of app to tell you which constellations are above your horizon tonight. In the old days, we used a planisphere... I still have one. https://en.wikipedia.org/wiki/Planisphere

Sort of like J002E3... https://en.wikipedia.org/wiki/J002E3

I used it (iteratively) to generate π once.

Do you know the constellations? If not, learn them. Once that's done, it becomes much easier to decide what to look at. You will need star charts. Wikipedia's aren't bad: https://en.wikipedia.org/wiki/Orion_%28constellation%29#/media/File:Orion_IAU.svg

We learned "Oscar Had A Heap Of Apples". But then you have to remember that the order is sin, cos, tan.

How realistic do you want to get? Solid rocket motors can have different thrust profiles by varying the shape of the burning surface of the fuel. What about air drag? Acceleration ("Gs") depends on those and also on whatever maneuvering is done. Guidance is complicated, especially if you're...

Yup. Back in pre-computer days, offices full of "computers" (i.e. human beings who punched adding-machine-type calculators) did the work. I have some older books (1930s-1940s) which show one how to organize the calculations for celestial mechanics with that method.

Indeed.

Yup, makes perfect sense.

An interesting question, which I have just seen for the first time... Does Kepler's 2nd mean that, for instance, both Pluto and Mercury sweep out an equal area over 1 hour? My gut reaction, without calculating anything, is "yes".

Also allows design of one board which can be "programmed" via jumpers to do a number of different things. Often used to disable/enable certain premium features.

Buy. Think of it as an investment. It doesn't have to be anything big and grandiose.

Yup, very common in industry practice. One incorporates a number of "jumpers" into the circuit design. Removing or adding zero-ohm resistors at those points selects certain circuit behavior - for instance, choice of 5V or 3.3V power.

Well, yes. Newton says the force between them (the Earth and whatever) is proportional to the product of their masses. Therefore, the Moon orbits a little faster, in the same orbit than say, a baseball. A basketball's orbit would not be noticeably different from the baseball's. What are you saying?

I once was behind a large truck. The trucker, I gather, did not like cyclists. Upon coming alongside one, he lugged the engine, or something, and blew out an enormous cloud of black soot all over him. I used to try to stay out of traffic when I rode.

Well, if the satellite's mass is large enough, it's not (independent of mass). For instance, the Moon. However, if the satellite's mass is something like 1 ten-billionth of the mass of the body it's orbiting, and another satellite's mass is 5 ten-billionths, then you will see negligible...

Gorilla glue (polyurethane glue) expands quite a bit as it cures - it foams up. So there is that to consider.

BTW, if you want to get deep into such things, may I recommend this author? http://www.willbell.com/math/mc1.htm

Depends on what you want out of it. If you start with heliocentric, J2000 pos/vel, you will get heliocentric, J2000 orbital elements. Just be careful in doing your comparisons with someone else's results (even NASA's) - if they started with, for instance, barycentric, J2000 pos/vel, their...

No, but it is annoying to have to learn "the Altium way" to do anything at all, even something relatively uncomplicated. Unlike, for instance, LTSpice, which you can use virtually immediately just by poking around a little. The board I wanted to design (with Altium) was very basic. I had to pore...

Ya know, I've never thought about it before... light for propulsion is always presented as an outside source fired at the craft.

I used Altium for one board design. Not at all intuitive. It took a couple of weeks to get where I could use it effectively.

Yes. One has to account for solar radiation pressure for exact calculations of (Earth) satellite orbits. Google "solar sail".

Pfft. Remember back in the 70's, when all of the studies said we should eat chemically hydrogenated oils instead of animal fats, because they were better for us?

Not immediately anyway. But then 10,000 or 100,000 years later, Jupiter, in its new orbit, has pumped up (or down) all of the inner planet's orbits hundreds of times. What about the asteroid belt - a new late,late heavy bombardment? Probably millions of years before it all settles down again...

11 of 13. Guessed a few of them.

Only if the target is near the plane of Earth's orbit... i.e. at the Ecliptic poles, this doesn't happen.