Physics of Star Killer Base

If you haven't seen the latest Star Wars ("The Force Awakens", episode 7), stop reading immediately! :)


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Apparently, there has been some griping about the physics of Star Killer Base.

For example, if the planet can't move, and even one shot substantially drains their sun - then you've only got a few shots from your super-weapon (not to mention everyone on the planet will freeze).

Also, if the weapon drains the whole star, then it is really massive overkill (about 12 trillion times according to one site).


There is a much more reasonable explanation!


The photosphere is the region of the Sun which emits visible light.  The key idea is "It [the photosphere] extends into a star's surface until the plasma becomes opaque"

If you strip off the photosphere, then the star will appear opaque i.e. black (at least, until it regenerates).

Ok, so how much energy can you get from the photosphere (we'll assume the Empire, err, First Order, has sufficient tractor beam and shield technology to extract it quickly and safely).


All of my calculations are in a Google Drive spreadsheet.


Final result?  Yes - there's about 1700 times more power than you need to blow up one planet just from fusing the hydrogen in the photosphere into helium (you could get more power by fusing up to iron).


And how rapidly could you fire such a weapon?

I'm not sure of the fluid dynamics, but keep in mind the regions of the photosphere last about 8 minutes (they are upwellings of cooling plasma).  Which implies it might recharge very rapidly indeed!

KOL Edit

A blast from the past!

Knights of Legend was one of my favorite games.  It was immensely detailed in every way.  It might take an hour to fight out a single quest! :)

Main problem - it was expected that additional "region packs" would round out the game.  But they never happened.  So, you get trainers who are not good enough to get you to the next level where the more advanced trainer will talk to you...

Enter the KOL Editor!  It will (eventually) allow you to train yourself (subtracting AP, and maybe gold) to level up your skills.

libHexPlanet: Sphere 7

I got sphere 6 working using a texture for the vertexes and sending position indices (I didn't get a chance to post the screen shot).

However, both my machines have limits of 256 KB for textures, this works out to 16384 vertexes, which is sphere 6.

I'm going to give up on indirection, and just spam all the vertices.  It took a little doing, but it's working.

Sphere 7:

And I can now do sphere 10, which is so detailed, the individual hexes are turning into pixels:

libHexPlanet: Shading!

I figured there should be a way to have the shader do the triangle/hex reprojection, and I found it!

The shader calculates the nearest point, and uses the terrain type (one byte) to pick a color.

Plates in libHexPlanet

I finished this a while back, but forgot to post an update...

This is sphere 9 (200k) hexes.  I've also significantly sped up generation so sphere 10 and 11 are pretty quick.

Now I need to figure out the math for plate collisions...

libHexPlanet

I'm always interested in world building, and I saw some talk about generating entire spheres of hexes.  This is not straight forward, since you can't make a sphere entirely out of hexes (you usually get twelve pentagons).

I saw one guy who embraced the variation, and would randomly make more pentagons (with a septagon to balance each past twelve).  He also moved the points around, so the whole map is a little irregular.

There is another project - HexPlanet, which just has the twelve pentagons.  I've found that code a lot easier to work with, and when you have 100k+ hexes, twelve pentagons is hardly noticeable...

I've finally got it into a state where I can easily generate some map data.  Here is sphere 9, which is nearly 200k hexes.  I should be able to get sphere 10 working (nearly 600k hexes), with an stretch goal of sphere 11 (should be over 1.5M hexes).

The terrain is a little hard to see, since it is entirely random.  But you can see how small the hexes are in sphere 9.

Youtube Filter Extension - Inception

There are a lot of young kids watching Youtube videos.  I went looking for the parental controls, and found Google's statement: Youtube is for people 13 and over.  To which I respond, hahahahahahaha

I thought about using a Squid proxy, but the video is encoded into a GET request, which Squid didn't seem ready to handle...

Then I saw this extension, and it looks like a good way forward...

Bridgehead

"Bridgehead" (David Drake) - I was unpleasantly surprised by this book.  I expect a lot more from Drake, and this was not up to his usual standard.  He took an unusual idea (FTL via some sort of row and column based system), and wrapped it up in a lot of mystery and drama (which are not his strong suit).  The combat was a fairly minor part of the book, and always one-sided.

C++: make the simple case broken

I've been programming C++ for twenty years, and I learned something yesterday about a fundamental class that I use a lot...

int main(int argc, char **argv)
{
   std::map<int, int> myMap;
   myMap.insert(std::make_pair(0, 1));
   myMap.insert(std::make_pair(0, 2));
   printf("%d\n", myMap[0]);
   return 0;
}

What should this program print?  1 or 2?  If you said 2, you'd be horribly wrong!

Because, sometimes, you just want your insert operations to fail.

If you don't want total failure, you need to write:

int main(int argc, char **argv)

{

   std::map<int, int> myMap;

   myMap.insert(std::make_pair(0, 1));

   std::pair::iterator, bool> i = myMap.insert(std::make_pair(0, 2));

   if (!i.second)

      i.first->second = 2;

   printf("%d\n", myMap[0]);

   return 0;

}

That's why I love C++.

Crowdsourcing your brainstorming

Back in the days of Mudge, it was easy to brainstorm an idea like industrial applications of black holes.

Now, it's harder.

I figured I would make use of the largest collection of nerds that I know about - Reddit (seeing as how Slashdot has gone down the tubes).

Reddit is divided into groups, and finding the right one can be somewhat of a challenge.

The most direct would be /r/AskScience, since it is really a science question (or, applied science).  But they take a dim view on science fictiony things.

There is also /r/AskScienceFiction, which sounds perfect.  Except, everything there is in role-playing form (it should be /r/AskLARP or something).  There are other more conceptual/design subreddits, but they are all low traffic.

So, I just had to ask my question in a RP fashion, and try and make sense of RP answers.

The answers weren't spectacular.  But I must give credit to /u/Sriad for the best one.  I had thought about using extreme matter compression, but I was thinking of something like a diamond press (which would not be forceful enough).  Treating it more like a fusion bomb makes a lot of sense.

"Trader's World"

"Trader's World" (Charles Sheffield) - I am really liking Sheffield.  This book reads like the Golden Age of SF, but is from 1988.  Reminds me of the Stainless Steel Rat.  Earth is recovering from WWIII, and the traders hold together the big nations through diplomacy and trade.

Starfarers

"Starfarers" (Poul Anderson) - I'm not sure what to say about this book.  The main idea is the development of a zero energy reactionless drive (so, no FTL, but lots of STL).  The story is told in two parts, the first follows the first star ship (traveling thousands of light years towards signs of other reactionless ships); the second follows the second generation explorers, settlers, and traders.

The two stories help to break up some of the monotony (not much happens in 495 pages - at one point, I broke out the old "I'm sorry, my friend, but you must die to make the movie more interesting!").  However, it seems like the whole thing could have been made shorter.

NedOS on real hardware!

It took some doing (and it's still not where it is on simulators), but it's something.

Voxel Worlds

I think I need to work on some sort of voxel world building game (aka Minecraft - or should I say, NedCraft, MiNed?)

Some numbers:
Figure 1 GB allocated for the world (which should fit nicely into memory on modern machines - you could go to 2 or 4, but not 10 or 20 yet).  One byte per block gives 255 active textures (plus empty).  That should be plenty (Minecraft has a ton of items and creatures, but those can be handled separately).

1e9 blocks sounds like a lot, until you start trying to fill a globe with them...

That's 1000 blocks cube, if each block is one meter, that's only a 1km cube (which is a pretty small planet).

You might use a lazy system for allocating, but that opens the possibility of the total storage growing enormous over time.

It seems better to limit the depth, and spread the blocks over a greater area...

Of course, you need some volume above the surface as well...

500 m high, 500 m deep... 1 GB goes fast!

Soylent People Are Green!

(you know, green, like they care about the environment)

I seem to remember something about some guy trying to develop a food replacement blend.  I didn't think much of it until I saw it on Ars, and checked out the blog.

"Suppose we had a default meal that was the nutritional equivalent of water: cheap, healthy, convenient and ubiquitous."

There is something in geek culture called "life hacking".  Just like you might hack software or hardware to scratch an itch, you can hack your body to make it a little better.

That's the approach here - the creator started with a personal project (simplify meals), and is now open sourcing it for everyone.  I think it will be interesting.

Gentoo Defeated Me

You know it's bad when you start thinking about finishing your own operating system, rather than wrestling with getting an existing one to work...

My old laptop has Ubuntu 10.4 (which expired June 1).  Lots of stuff has started breaking, I've known I needed to update the OS for a long time.

I hate 12.4 (which was the natural upgrade), so I figured I would try Gentoo.  I'd be able to build any software I need.

I've been trying to build Gentoo on two machines since December.  Neither works.  They have different processors and graphics, but, ironically, they both fail in the same place (X server fails to load KMS module).

I just pulled the Gentoo live DVD, and it looks good.  X starts up (although my wireless isn't recognized...).  I looked for a "Install this!" button, but alas, no such thing.

I searched for "Install Gentoo from live dvd".  I found a forum post which pointed to a wiki page.  The wiki page wouldn't load, so I had to go through the Google cache, only to discover the page was deleted - due to incompatible license.  Wonderful.

LoN for Noobs: Starting Out

Light of Nova has its own unique quirks which set traps for the unwary, and hide gems from the uninformed.  I'll try and shed some light on them:

1. Starting out, don't worry about any mothership modules apart from crystal and metal gathering.  Build the others to collect the training rewards, but focus on these two.  (I'll post a queuing guide next)
2. Do the first adventure - that will give you a new commander.  The next commander is a ways in.  Best to hit those with better tech.
3. Find a governor and a main fighter.

You want a governor with metal or crystal skill (ideally both, but that rarely happens).  Fuel is useless.  Crystal is needed for research, while metal is needed for advanced flagships.

Your main fighter will have tempest skill (and ideally vulcan or destroyer).  This is because the computer guys love fighters and are optimized for killing cruisers and battleships (and fighters are too flimsy for big fights).

You will get fifteen commanders over time, and have upwards of six planets (each needs a governor).  You will want a battleship commander, and Longbow commanders are good for killing enemy player's flagships.

Use your experience potions on your governor (your fighter will get plenty of xp from fighting).  Don't worry too much about rank at first.  You can rank up your governor with medals a couple times to get him more points for politics skill and his resource specialization.

Light of Nova

I finally found a Stars-like that people are playing (and it was even on Facebook!)

The mechanics are pretty straightforward (build, build, build), and politics plays a pretty important part.  There is even a story that is not entirely terrible.

And I've got a spreadsheet!

Manic Digger

Been having a blast in Manic Digger.

It's an open source clone of Minecraft.  One of the cool features is seasons; in the winter, the top layer of water freezes, and you can pick up "water" blocks.

Then, you can take those blocks and drop them somewhere, and create waterfalls.

The mountain on the left has already been covered, and you can see the water starting to flow on the mountain in the distant center.

I was working in a mine when the water hit the bottom, and found myself having to fight a flood in!

Hell's Faire

"Hell's Faire" (John Rngo) - This is the fourth book in the Posleen trilogy.  Apparently, Ringo was finishing the third book when 9/11 happened, and got writer's block through press time.  This book continues where the third left off (plus a small - "we last left our heros"), and finishes the war on Earth.

Ringo says in the afterword that this series was written for his enjoyment (not intended for publishing).  If you don't take it too seriously, it is definitely fun.  The Sheva (named Bun Bun, after Sluggy Freelance) gets up-armored and close support weapons and fights its way towards the main character.