Today I Learned 2021

I’m going to start keeping a list of random facts I learn. I’m primarily recording natural organic discoveries which come out of conversations with real people in real life, rather than forced discoveries from online sources like reddit’s TIL or interactions with random internet people I’ve never met (“friends” in Newspeak). This means that most entries will have a personal story behind it, although I’m not recording those stories so it’ll be an exercise for the reader to imagine what was being discussed at the time. There’s actually a couple from late 2020 to make up for the fact that I decided to do this a little after the start of 2021.

10 Nov 2020: There’s a breed of semi-feral sheep on a small Scottish island that has evolved to eat mostly seaweed

Apparently it gives the meat a “unique, rich flavour”:

21 Dec 2020: When my children are making pretend phone calls they place flat palms towards their face, like a smart-phone

(Not so much Today I Learned, but Today I Noticed.) Whereas when I make pretend phone calls I have my fist by my cheek with my little finger out towards my mouth and my thumb out towards my ear, like a traditional telephone handset.

12 Feb 2021: Mars has 2 moons - Phobos and Demios

(I suspect I knew this as a child but subsequently forgot.)

13 Mar 2021: There’s a type of shark which has jaws that extend outwards dramatically when feeding

It is called the goblin shark, and inspired the alien jaws in Alien Covenant:

13 Mar 2021: The phrase “wild goose chase” was popularised by Shakespeare’s Romeo and Juliet

Although the phrase itself may have pre-dated the play:

3 June 2021: Dogs only see in blue and yellow

15 June 2021: The time dilation effect of special relativity increases dramatically as the speed of light is approached

What this means is that the “travel time” (i.e. the time experienced by the traveller) only starts shortening dramatically as the speed of light is reached, while the “proper time” (i.e. for a non-traveller) doesn’t change as much. For example, to travel the 4.246 light years to the nearest star (Proxima Centauri), the “travel time” would be 4 years at 90% of the speed of light, 1 year at 99%, 131 days at 99.9%, 41 days at 99.99%, 13 days at 99.999%, etc., while the “proper time” would be 8.9 years at 90%, 8.1 years at 99%, 8.0 years at 99.9%, 8.0 years at 99.99%, 8.0 years at 99.999%, etc.:

30 June 2021: An “exonumist” is a person who collects exonumia

Exonumia are numismatic items other than legal tender coins and paper money, e.g. tokens, souvenir medallions, casino chips.

2 Jul 2021: The phrase “gardyloo” was only used in Scotland

The phrase “gardyloo” was shouted in medieval times to warn those below that toilet waste was about to be thrown out of the window. I learned the phrase at school, and have periodically told others of it since. I had always assumed it was used UK-wide, but apparently it was only used in Scotland. I wonder what they said in England. Or maybe they didn’t say anything on warn those below before throwing their toilet waste out of the window. (And yes, the English also threw toilet waste out I the window in medieval times.) While I’m here, I learned a few weeks back that “squint” in England only means to narrow one’s eyes, whereas in Scotland it can also mean wonky or askew, so all the times in England I’ve said something like “the picture’s a bit squint”, the English won’t have understood what I meant.

10 Jul 2021: The darker outer ring some people have in their eyes is called a “limbal ring”

16 Aug 2021: Some words in some languages don’t have direct translations because they require a different way of thinking

As an example: “Gaelic colours reflect the quality of light and natural environment of the islands and do not always correspond to English names”

18 Aug 2021: Afghanistan shares a small border with China

6 Sep 2021: There aren’t any photos of Neil Armstrong on the moon

Buzz Aldrin had a camera and took lots of photos, but didn’t think to take any with Neil in. Neil also had a camera, but thought to take photos with Buzz in.

16 Sep 2021: Sign language includes some visual puns

e.g. the sign for pasteurised milk involves moving ones hand “past your eyes”.

22 Oct 2021: Marshmallows on a hot chocolate aren’t just flavouring - they also serve a function

The marshmallows act as an insulating layer, allowing you to put squirty cream on the hot drink without it just melting and sinking.

1 Nov 2021: Hallow is an archaic term for a saint or holy person

Hence All Hallows Day also being known as All Saints Day.

17 Nov 2021: The odor added to natural gas in the UK was changed so as not to be confused with rotting vegetables

Natural gas, as piped to many UK homes, is odorless, but “odorized” to help people detect leaks. The original odorizer used in the UK (THT) was often confused with rotting vegetables though, so a new odorizer was introduced (80% TBM 20% TBM) which has a very distinctive odor and is therefore difficult to confuse with anything else.

So all those jokes in cartoons about “we can’t afford to licence the “Happy Birthday To You” song pre-date 2015. In Europe would have expired in 2017 anyway.