The Universe of Disco


Sun, 31 Mar 2024

Stuff that is backwards in Australia

I thought at first was going to be kind of a dumb article, because it was just going to be a list of banal stuff like:

  • When it's day here, it's night there, and vice versa

but a couple of years back I was rather startled to realize that in the Southern Hemisphere the sun comes up on the right and goes counterclockwise through the sky instead of coming up on the left and going clockwise as I have seen it do all my life, and that was pretty interesting.

Then more recently I was thinking about it more carefully and I was stunned when I realized that the phases of the moon go the other way. So I thought I'd should actually make the list, because a good deal of it is not at all obvious. Or at least it wasn't to me!

  1. When it's day here, it's night there, and vice versa. (This isn't a Southern Hemisphere thing, it's an Eastern Hemisphere thing.)

  2. When it's summer here, it's winter there, and vice versa. Australians celebrate Christmas by going to the beach, and July 4th with sledding and patriotic snowball fights.

  3. Australia's warmer zones are in the north, not the south. Their birds fly north for the winter. But winter is in July, so the reversals cancel out and birds everywhere fly south in September and October, and north in March and April, even though birds can't read.

  4. The sun in the Southern Hemisphere moves counterclockwise across the sky over the course of the day, rather than clockwise. Instead of coming up on the left and going down on the right, as it does in the Northern Hemisphere, it comes up on the right and goes down on the left.

  5. In the Northern Hemisphere, the shadow of a sundial proceeds clockwise, from left to right. (This is the reason clock hands also go clockwise: for backward compatibility with sundials.) But in the Southern Hemisphere, the shadow on a sundial goes counterclockwise.

  6. In the Southern Hemisphere, the designs on the moon appear upside-down compared with how they look in the Northern Hemisphere. Here's a picture of the full moon as seen from the Northern Hemisphere. The big crater with the bright rays that is prominent in the bottom half of the picture is Tycho.

    Photo of the moon as seen
from the Northern Hemisphere

    In the Southern Hemisphere the moon looks like this, with Tycho on top:

    Photo of the moon as seen
from the Northern Hemisphere

    Australians see the moon upside-down because their heads are literally pointing in the opposite direction.

  7. For the same reason, the Moon's phases in the Southern Hemisphere sweep from left to right instead of from right to left. In the Northern Hemisphere they go like this as the month passes from new to full:

    New moon, all dim Bright crescent on the right-hand edge Bright on the right half Bright except for a dim crescent on the left-hand edge Full moon, all bright

    And then in the same direction from full back to new:

    Full moon, all bright Bright except for a dim crescent on the right-hand edge Dim on the right half Dim except for a bright crescent on the left-hand edge New moon, all dim

    But in the Southern Hemisphere the moon changes from left to right instead:

    New moon, all dim Dim except for a bright crescent on the left-hand edge Dim on the right half Bright except for a dim crescent on the right-hand edge Full moon, all bright

    And then:

    Full moon, all bright Bright except for a dim crescent on the left-hand edge Bright on the right half Bright crescent on the right-hand edge New moon, all dim

    Unicode U+263D and U+263E are called FIRST QUARTER MOON ☽ and LAST QUARTER MOON ☾ , respectively, and are depicted Northern Hemisphere style. (In the Southern Hemisphere, ☽ appears during the last quarter of the month, not the first.) Similarly the emoji U+1F311 through U+1F318, 🌑🌒🌓🌔🌕🌖🌗🌘 are depicted in Northern Hemisphere order, and have Northern Hemisphere descriptions like “🌒 waxing crescent moon”. In the Southern Hemisphere, 🌒 is actually a waning crescent.

  8. In the Northern Hemisphere a Foucault pendulum will knock down the pins in clockwise order, as shown in the picture. (This one happens to be in Barcelona.) A Southern Hemisphere Foucault pendulum will knock them down in counterclockwise order, because the Earth is turning the other way, as viewed from the fulcrum of the pendulum.

  9. Northern Hemisphere tornadoes always rotate counterclockwise. Southern Hemisphere tornadoes always rotate clockwise.

Dishonorable mention

As far as I know the thing about water going down the drain in one direction or the other is not actually true.

Addendum 20240414

Several people took issue with some of the claims in this article, and the part about sundials was completely wrong. I wrote a followup.


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Fri, 08 Mar 2024

Werewolf ammunition

This week I read on Tumblr somewhere this intriguing observation:

how come whenever someone gets a silver bullet to kill a werewolf or whatever the shell is silver too. Do they know that part gets ejected or is it some kind of scam

Quite so! Unless you're hunting werewolves with a muzzle-loaded rifle or a blunderbuss or something like that. Which sounds like a very bad idea.

Once you have the silver bullets, presumably you would then make them into cartidge ammunition using a standard ammunition press. And I'd think you would use standard brass casings. Silver would be expensive and pointless, and where would you get them? The silver bullets themselves are much easier. You can make them with an ordinary bullet mold, also available at Wal-Mart.

Anyway it seems to me that a much better approach, if you had enough silver, would be to use a shotgun and manufacture your own shotgun shells with silver shot. When you're attacked by a werewolf you don't want to be fussing around trying to aim for the head. You'd need more silver, but not too much more.

I think people who make their own shotgun shells usually buy their shot in bags instead of making it themselves. A while back I mentioned a low-tech way of making shot:

But why build a tower? … You melt up a cauldron of lead at the top, then dump it through a copper sieve and let it fall into a tub of water at the bottom. On the way down, the molten lead turns into round shot.

That's for 18th-century round bullets or maybe small cannonballs. For shotgun shot it seems very feasible. You wouldn't need a tower, you could do it in your garage. (Pause while I do some Internet research…) It seems the current technique is a little different: you let the molten lead drip through a die with a small hole.

Wikipedia has an article on silver bullets but no mention of silver shotgun pellets.

Addendum

I googled the original Tumblr post and found that it goes on very amusingly:

catch me in the woods the next morning with a metal detector gathering up casings to melt down and sell to more dumb fuck city shits next month


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Wed, 06 Mar 2024

Optimal boxes with and without lids

Sometime around 1986 or so I considered the question of the dimensions that a closed cuboidal box must have to enclose a given volume but use as little material as possible. (That is, if its surface area should be minimized.) It is an elementary calculus exercise and it is unsurprising that the optimal shape is a cube.

Then I wondered: what if the box is open at the top, so that it has only five faces instead of six? What are the optimal dimensions then?

I did the calculus, and it turned out that the optimal lidless box has a square base like the cube, but it should be exactly half as tall.

For example the optimal box-with-lid enclosing a cubic meter is a 1×1×1 cube with a surface area of !!6!!.

Obviously if you just cut off the lid of the cubical box and throw it away you have a one-cubic-meter lidless box with a surface area of !!5!!. But the optimal box-without-lid enclosing a cubic meter is shorter, with a larger base. It has dimensions $$2^{1/3} \cdot 2^{1/3} \cdot \frac{2^{1/3}}2$$

and a total surface area of only !!3\cdot2^{2/3} \approx 4.76!!. It is what you would get if you took an optimal complete box, a cube, that enclosed two cubic meters, cut it in half, and threw the top half away.

I found it striking that the optimal lidless box was the same proportions as the optimal complete box, except half as tall. I asked Joe Keane if he could think of any reason why that should be obviously true, without requiring any calculus or computation. “Yes,” he said. I left it at that, imagining that at some point I would consider it at greater length and find the quick argument myself.

Then I forgot about it for a while.

Last week I remembered again and decided it was time to consider it at greater length and find the quick argument myself. Here's the explanation.

Take the cube and saw it into two equal halves. Each of these is a lidless five-sided box like the one we are trying to construct. The original cube enclosed a certain volume with the minimum possible material. The two half-cubes each enclose half the volume with half the material.

If there were a way to do better than that, you would be able to make a lidless box enclose half the volume with less than half the material. Then you could take two of those and glue them back together to get a complete box that enclosed the original volume with less than the original amount of material. But we already knew that the cube was optimal, so that is impossible.


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Mon, 04 Mar 2024

Children and adults see in very different ways

I was often struck with this thought when my kids were smaller. We would be looking at some object, let's say a bollard.

The kid sees the actual bollard, as it actually appears, and in detail! She sees its shape and texture, how the paint is chipped and mildewed, whether it is straight or crooked.

I don't usually see any of those things. I see the bollard abstractly, more as an idea of a “bollard” than as an actual physical object. But instead I see what it is for, and what it is made of, and how it was made and why, and by whom, all sorts of things that are completely invisible to the child.

The kid might mention that someone was standing by the crooked bollard, and I'd be mystified. I wouldn't have realized there was a crooked bollard. If I imagined the bollards in my head, I would have imagined them all straight and identical. But kids notice stuff like that.

Instead, I might have mentioned that someone was standing by the new bollard, because I remembered a couple of years back when one of them was falling apart and Rich demolished it and put in a new one. The kid can't see any of that stuff.


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Sun, 03 Mar 2024

Even without an alien invasion, February 22 on Talos I would have been a shitshow

One of my favorite videogames of the last few years, maybe my most favorite, is Prey. It was published in 2017, and developed by Arkane, the group that also created Dishonored. The publisher (Bethesda) sabotaged Prey by naming it after a beloved 2006 game also called Prey, with which it had no connection. Every fan of Prey (2006) who was hoping for a sequel was disappointed and savaged it. But it is a great, great game.

(I saw a video about the making of the 2017 Prey in which Raphael Colantonio talked about an earlier game of theirs, Dark Messiah of Might and Magic, which was not related to the Might and Magic series. But the publisher owned the Might and Magic IP, and thought the game would sell better if it was part of their established series. They stuck “Might and Magic” in the title, which disappointed all the Might and Magic fans, who savaged it. Then when Bethesda wanted to name Prey (2017) after their earlier game Prey (2006), Colantonio told them what had gone wrong the previous time they tried that strategy. His little shrug after he told that story broke my heart a little.)

This article contains a great many spoilers for the game, and also assumes you are familiar with the plot. It is unlikely to be of interest to anyone who is not familiar with Prey. You have been warned.

(If you're willing to check it out on my say-so, here's a link. I suggest you don't read the description, which contains spoilers. Just buy it and dive in.)


A recent question on Reddit's r/prey forum asked what would have happened if the Typhon organisms had not broken out when they did. The early plot of Prey is all there, but it is a little confusing, because several things were happening at once. The short answer to the question though, is that February 22, 2035 would have been the worst day of Alex Yu's life even if his magnificent space station hadn't been overrun by terrifying black aliens.

Morgan escapes the sim lab anyway

January had contingency plans for at least two situations. One was a Typhon escape, which we know all about.

But there was another plan for another situation. Morgan was having her memory erased before each round of testing. January explains that there was a procedure that was supposed to bring Morgan back up to speed after the tests were over. We know this procedure was followed for some time: Morgan's office has been used. Her assistant Jason Chang still hasn't gotten over his delight at working for such a hot boss. There are puzzled emails around asking why she never remembers her office combination. There's painful email from Mikhaila asking why Morgan is snubbing her. Clearly, at some point in the recent past, Morgan was still walking around the station in between tests, working and talking to people.

January's second contingency plan was in case Alex stopped bringing Morgan back up to speed after each round of tests, and just kept her in the simulation day after day — perhaps even more than once per day. (No wonder her eye is red!) And crucially, that plan was already in motion on February 22, the day the Typhon escaped.

The first thing that happens to the player in Prey is that Morgan fails all the tests. (“Is she…” “Yes, she's… hiding behind the chair.”) Why? We find out later Morgan was supposed to receive neuromods that would give her Typhon powers such as mimicry. They didn't. Marco Simmons says he installed exactly what Patricia brought down. There's email in the sim lab that asks Neuromod to check that something isn't wrong with the production process. But nothing is wrong with the production process. What really went wrong is that January had secretly replaced the neuromods with fakes, so that when they were removed from Morgan's brain, her memory wouldn't be affected. The next time Morgan woke up in her apartment and it was still March 15, she would realize what was happening.

It's hard to guess just what would have happened next, but I'm sure it would have been rather dramatic.

But that's not all

There are at least five other situations that would have blown up that same day. February 22 2035 on Talos I was always going to be an incredible shitshow.

  1. Emmanuel Mendez

    Because Frank Jones is a fuckup, Emmanuel Mendez has become aware that the escape pods don't work. He has decided to alert the crew by reprogramming the giant floating billboards to display “ESCAPE PODS ARE FAKE”. He completes this task on February 22 but dies without activating the program that will change the display.

    Those billboards are visible from everywhere on the station, including the cafeteria.

  2. Halden Graves

    Halden Graves, head of the Neuromod Division, has just figured out that the neuromods, even the non-Typhon ones, are made with exotic material from the Typhon, and he completely loses his shit, to the point of chopping open his own head to get them out. That might attract some attention.

  3. Josh Dalton

    On February 22, Josh Dalton murdered Lane Carpenter with the BFG 9000 and then fled with it into the GUTS.

  4. Alton Weber

    Weber is on the Life Support security team. He has had a paranoid breakdown and stolen a shotgun. There's probably going to be a firefight outside the Life Support restrooms.

  5. Mikhaila Ilyushin

    Mikhaila is about to be arrested. Alex already suspected that something about her was fishy. Mikhaila has sent Divya Naaz to install snooping devices in the doors in Psychotronics, and Divya has been caught. Alex isn't going to wait any longer to stop Ilyushin.

Coming soon

These are starting to fall apart but the shit won't really hit the fan until sometime after February 22.

  1. Annelise Gallegos and Quinten Purvis

    Annelise Gallegos has been overcome by her conscience and is blowing the whistle on the experiments in Psychotronics and the murder of the “Volunteers”. On February 22, Alex has ordered Sarah Elazar to arrest her, as soon as her shift is over. The Typhon escape prevents that. What would have happened to Gallegos? I suspect she would would have died in an ⸢unfortunate accident⸣.

    But it's too late for the Yus. Gallegos has already prepared her thumb drive with all the damning evidence, and Quinten Purvis has hidden with it in a cargo container. If the Typhon hadn't gotten loose that day, he would have been on his way to Earth with it.

    [ Addendum 20240327: There's a hint that Sarah Elazar is on the trail, and I think I remember that she has sent someone to investigate the cargo hold, but it's not clear that they would have been able to stop Purvis. ]

  2. Hunter Hale

    Shuttles are supposed to take the Volunteers back to Earth when their service is complete. The Shuttle Bay flight control staff have recently noticed that the shuttles are not going straight back to Earth, but are stopping somewhere else just after leaving, and then proceeding to Earth on a slightly altered course.

    What's really happening is that the shuttle pilot, Hunter Hale, makes a stop at the Psychotronics airlock and drops off some or all of the Volunteers so they can be turned into Neuromods.

    Alex is paying Hale five times the normal salary to keep his mouth shut about this, but HR has noticed and is asking questions about it. Between the flight control staff and HR, the truth is going to come out.

    [ Addendum 20240327: The security staff has brought the suspicious shuttle course to the attention of Sarah Elazar, who is going to investigate. ]

  3. Sarah Elazar

    Elazar suspects that the Yus are up to something dirty. She doesn't know what yet, but she's going to find out.

  4. Disappearing neuromods

    Everyone seems to be pilfering neuromods. Emmanuella Da Silva has some stashed in the drop ceiling of the Shuttle Bay locker room. Yuri Kimura has four under her desk, and Elias Black is blackmailing her. Lorenzo Calvino has some in both of his secret safes. Lily Morris has them hidden in the fire alarms in half a dozen places around the station. That dumbass Grant Lockwood has tried to walk back to Earth with his stolen neuromods.

    I probably missed a few, they're all over.

    (I said none of this would come to light until after February 22, but it won't be long before someone wonders what became of Lockwood. It's also possible Alex will find out about the Lily Morris conspiracy that day, from Eddie Voss. I almost feel sorry for Alex.)

    [ Addendum 20240327: Elazar, as usual, is on the ball. She knows Lockwood is missing and has dispatched someone to find him. ]

Minor shit

Not giant disasters, but troublesome nevertheless.

  1. Lorenzo Calvino

    It won't be long before someone, probably Miyu Okabe, figures out that Lorenzo Calvino has a severe, progressive mental impairment.

  2. Price Broadway

    Broadway, the alcoholic in Waste Processing, is endangering everyone's lives by leaving empty vodka bottles in the eel tanks. His supervisor knows and has reported him to HR. She says HR will help, but I imagine they'll just fire him.

    Maybe he'll end up on Hunter Hale's shuttle home.

  3. Volunteers

    What's up with the Volunteers in the dormitory in Neuromod Division? Some of them are stealing and selling supplies. Other are stealing dangerous equipment and weapons. What for?

Drama drama drama

Even without the Typhon, Prey could have been a great game!

You play Morgan, of course. The first fifteen minutes are the same, right up until Bellamy would have died.

When you wake up for the second time on March 15, you figure out what is happening, and confront the Sim Lab staff. You escape, go rogue, and make your way to the Arboretum to confront Alex. Meanwhile all sorts of stuff is going down. Alton Weber is on a rampage in Life Support. Josh Dalton is loose in the GUTS. You'll have to deal with him to get to the Arboretum. (What, did you think you were going to take the elevator?) Somewhere along the line you find out about Purvis in the cargo container and have to decide how to handle that. And then Mendez changes the billboards and there's a panic…

What else?

A lot is happening on Talos I. I probably left something out.

(The shortage of escape pods doesn't count. Someone would have noticed long ago that there aren't nearly enough. I think we have to assume that there are more escape pods than we see in the game. Perhaps Morgan's simulation omitted them.)

(And in my headcanon, that poor schmuck Kevin Hague never does find out his wife has cheated on him with the asshole football star.)

Let me know what I missed.


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