Moonwards

Hohmannfan

15:00

I think wolframalpha is drunk

kim holder

what. is. that.

Hohmannfan

It just continued to spit out page after page of that. Me thinks I have something wrong in my input

kim holder

what you have wrong must be rather interesting. you sure made it think.

Hohmannfan

solve E = ( M/(x * p + cm * (x + c - f)^2/x) )^2 * p + ( (x + c - f) * M/(x * p + cm * (x + c - f)^2/x )/x )^2 * cm - p * gm/x - cm * gm/(x + c - f)

It grew into a nightmare, so wolfram was a last desperate attempt.

I must find a new strategy

kim holder

what is it for?

Hohmannfan

15:05

I am trying to figure out some tether mechanics.

how tether docking affects eccentricity.

kim holder

oh, yay :D

Hohmannfan

But yeah, this is a failed case

kim holder

i am glad it is stretching your skills.

that's what you want at this point in life.

i sort of want to ask what the elements of it are, but i have serious doubts there would be any point in telling me.

Hohmannfan

Short version: both momentum and energy is the same before and after the drop. I am trying to find a way to express the size of the drop.

kim holder

that would certainly be tremendously useful

Hohmannfan

15:20

Solve for "drop" and we are done.

kim holder

would you like to ask about it on SX?

Hohmannfan

no

maybe

meh, why not.

kim holder

perhaps it is better to work it out on your own, but that looks like Hop bait to me.

and there are a few who would probably simply find it interesting

i was wondering how to turn the spreadsheet into something more useful

Hohmannfan

Then I have to draw some pretty diagrams

kim holder

that always makes hard-core SX people happy

maybe the spreadsheet should be a download, like Hop and Chris Wolfe did for theirs

Hohmannfan

15:30

Initial situation.

kim holder

aw, it's cute :D

Hohmannfan

Hop can not resist this bait

kim holder

of course he can't

Hohmannfan

Today I learned about stroke-dasharray="number,number"

kim holder

[kim copies that into her browser]

svg magic stuff i do also want to learn

Hohmannfan

15:39

"Calculate docking drop of orbital tether" or "How to calculate docking drop of orbital tether" or "How can I calculate the docking drop of an orbital tether?" or something else?

kim holder

i am inclined towards choice 2

wait, 'How to calculate drop due to ship docking at orbital tether'

Hohmannfan

ok

kim holder

(but without the typo i just fixed)

Hohmannfan

15:51

Perhaps I can add the classic "thank you in advance" :P

kim holder

:P

too on the nose...

Hohmannfan

space-tether, orbital-mechanics, more tags?

kim holder

docking?

Hohmannfan

good

kim holder

it should maybe be berthing...

i doubt we have a tag for each, or that it would be useful to have both...

Hohmannfan

15:55

the berthing tag exist. It has 6 questions...

space.stackexchange.com/tags/berthing/info

kim holder

yeah, i'd say since it wouldn't be a precision maneuver like docking, it would be better to change docking in the title to berthing

and switch the docking tag to berthing

in fact in fairness it might be more like grappling, but we can hope it would be berthing

Hohmannfan

though we have no idea how it is going to work in reality.

kim holder

sshhh...

Hohmannfan

docking, berthing, grabbing, hooking, hoping, missing, catching, failing,

kim holder

i do believe you can legitimately link to Moonwards in this question

Hohmannfan

16:01

perhaps moonwards.com/machines2.html#TetherTransport

but I have to fix the animation first. It fails on the second run

kim holder

oh yeah, i forgot to mention that to you

i wonder if the terminology should be switched from vertical tether to vertical skyhook

on moonwards - here it is sort of a different issue

i always find myself referring to the whole complex as the tether, and to the actual tether part as the cable, which is confusing

besides which, what 'tether' actually means is a rope or some such that is fixed at one end, and has something moveable on the other.

Hohmannfan

16:25

I fixed the animation.

kim holder

awesome. let me push that and some other changes to the site.

Hohmannfan

I uploaded it

kim holder

to the site?

Hohmannfan

yes

kim holder

ok

then i'll push all the places i changed 'tether' to 'skyhook'

hm, on chrome it is still a little broken

after the animation runs the first time, the ship is placed in the wrong spot

Hohmannfan

16:30

It is just slightly rotated, right?

kim holder

a bit rotated, and a bit to the right.

Hohmannfan

But it does not look very bad, so I am not going to spend time finding the guilty fill="freeze"

kim holder

yeah, not a priority

Hohmannfan

And of course stroke-dasharray can be animated :)

I added the source files to the repo, because why not. img/tetherDocking1.svg and 2

kim holder

ah, yes, that might come in useful at some point

would you call an orbit at 5000 km around the moon a medium lunar orbit?

Hohmannfan

16:41

It is certainly not low.

kim holder

wikipedia says low orbit is less than 100 km, and i think i'll tack a 'citation needed' onto that.

that's for the Lunar Orbit entry

Hohmannfan

So you are the person adding tags on wikipedia. Now I know.

kim holder

:))

Hohmannfan

The "learn" and "teach" distinction does not usually exist in Norwegian. I think that is the reason I am doing it wrong.

kim holder

16:57

i run into that in various situations in spanish

kim holder

17:28

it seems i can't actually add a 'citation needed' on wikipedia. you need to have more privileges.

at least, i couldn't find any way to do it, and finally i added a comment on the talk page.

Hohmannfan

18:35

Is there something similar to svg+smil in 3d? 3d models are almost exclusively vector anyway, so how is animation usually done?

kim holder

blender uses python

i have only done very simple things along these lines, and it was through an interface where you only have to put in the formula

the math is done in python notation

Hohmannfan

How can you write models as text? That would be useful.

kim holder

the models themselves? surely that wouldn't be advisable unless you were dealing with really simple shapes.

i don't know how you extract that from blender. there must be a way.

at the stage of optimization, perhaps there would be advantages, but i don't know...

the only times i have used formulas, it was to define movement.

Hohmannfan

Is the only way into 3d development to watch five hours of blender tutorials a day?

kim holder

heheheheh. it helps a lot to pick the right ones. i sent you a list a while ago.

if you want to do something specific, i can probably ease the burden by answering questions.

in fact, it might be useful to put the model on the repo, and i can do bits, and you do other bits.

it would make it more focused and less frustrating

kim holder

19:21

ok, important moment for me. i've finally named the main bases.

i'm changing Peary to Inuksuk.

Inuksuk

An inuksuk (plural inuksuit) (from the Inuktitut: ᐃᓄᒃᓱᒃ, plural ᐃᓄᒃᓱᐃᑦ; alternatively inukhuk in Inuinnaqtun, iñuksuk in Iñupiaq, inussuk in Greenlandic or inukshuk in English) is a human-made stone landmark or cairn used by the Inuit, Inupiat, Kalaallit, Yupik, and other peoples of the Arctic region of North America. These structures are found from Alaska to Greenland. This region, above the Arctic Circle, is dominated by the tundra biome and has areas with few natural landmarks. The inuksuk may have been used for navigation, as a point of reference, a marker for travel routes, fishing places...

The station on the earth tether is Anshar

Anshar

In the Sumerian, Akkadian, Assyrian and Babylonian creation myth Enuma Elish, Anshar (also spelled Anshur), which means "whole heaven", is a primordial god. His consort is Kishar which means "Whole Earth". They were the children of Lahamu and Lahmu and the grandchildren of Tiamat and Apsû. They, in turn, are the parents of Anu, the god of heaven, lord of constellations, king of gods, spirits and demons. If this name /Anšar/ is derived from */Anśar/, then it may be related to the Egyptian hieroglyphic /NṬR/ ("god"), since hieroglyphic Egyptian /Ṭ/ may be etymological */Ś/. == References == ��2...

i'm so proud...

Hohmannfan

20:06

Congrats

kim holder

;]

there is also Gagarin, that is the equatorial asteroid base, and of course Cernan's Promise.

Hohmannfan

I think I just realized what is good with a large library of svg illustrations. They are easy to use as building blocks for later illustrations, you just place them inside <g> tags, translate, scale and rotate them.

kim holder

also extremely true in 3d

it mushrooms after a while. it's a big relief.

Hohmannfan

mushroom is a verb?

kim holder

it can be used that way.

english is pretty flexible like that. that's why google quickly became a verb.

Hohmannfan

20:17

google is starting to become a verb here as well. It is very frustrating.

kim holder

:] back in the day the English deplored the Americans for breaking all sorts of grammar rules and inventing new words.

but they couldn't stem the tide. Now English is a lot more flexible thanks almost entirely to English colonies.

Hohmannfan

But inventing words and importing words are two different things

kim holder

well, yes...

but hey, it really is mostly thanks to Google that searching for a term gives you such useful results.

Hohmannfan

I like how Icelandic invents new words for almost everything instead of importing the English word

Yandex is older than Google though.

kim holder

i don't know how Yandex was in the early days, but before Google, search engines here were awful.

the results were loaded with things that gamed the system, or with businesses that simply paid to be displayed near the top.

Hohmannfan

20:27

I do not know how it was, I got online only a few years ago.

kim holder

Google revolutionized that. Their importance is often underestimated by the young

in all seriousness, if Google was not so committed to finding the most relevant results, all across all the sites on the whole internet, the usefulness of the Internet would be a pale shadow of what it is.

i remember how refreshing it was to use Google, and discover so much real information, and actually helpful material

kim holder

22:40

as soon as the timeline is finished it going to need to be split up and rearranged using tooltipster and details tags into something far less sprawling.

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