The gravity of the situation

Most of today was spent writing a new article for 100 Proofs that the Earth is a Globe. It’s about the variation in the strength of gravity over the Earth’s surface. It was hard finding a map of the actual value of the acceleration due to gravity across the Earth, rather than maps showing the local anomalies compared to a smoothly varying reference value. There are hundreds of the latter, but I only found one of the former, copied on a few different blogs, and it wasn’t clear where the original came from. I finally tracked it down to the Western Australian Geodesy Group at Curtin University, but the link I found led to a 404 page. So I emailed the professor of the research group there to ask if the diagram was really made by them, and if not, if he knew where it came from. I haven’t heard back yet, but I’ll update the article if and when I do.

For lunch I went on a longish walk over to a bakery called The Grumpy Baker, near the dog park where I take Scully a couple of times a week. With Scully we always drive because it’s a bit far to walk with her, but I did the trip on foot today, almost 5 km there and back. The weather was glorious – it really felt like summer already, even though we’re barely a few days out of winter. I walked there on an inland route, and then walked back by the shore of the harbour to make it a loop. This is Oyster Cove:

Fence and boat

And then this afternoon the temperature got even warmer. Between 4pm and 4:30pm the temperature rose by 6.2 degrees Celsius (11.2 degrees Fahrenheit). Yes, in half an hour! A strong westerly wind was bringing in hot air from central Australia. The wind was really strong too, gusting up to 100 km/hr across Sydney, and causing some significant structural damage and bringing down several trees. A few cars got crushed and people hospitalised, and there were blackouts from power lines being downed. Nothing severe near me, but there were some small tree branches littered about the road. And when my wife and I walked up the street for dinner, the fire brigade was dealing with a damaged tree as we walked past.

And then later it rained, very heavily, while we were eating dinner. That brought a steep drop in temperature, back down 10 degrees Celsius (18 degrees Fahrenheit) between 6 and 7pm. Fortunately the rain stopped before we walked back home, but the walk was uncomfortably cold.

Today I also raided the garage to find tools to install the new kitchen shelves I bought from the hardware store on Tuesday. I found an electric drill, but no bits. I’ll probably have to go buy the bit I need.

New content today:

Rainy day writing

It rained more today, heavier than yesterday. I wrote Irregular Webcomic! scripts in the morning while listening to the music of Five Year Mission.

After lunch I collected Scully from my wife’s work, and then had to keep her amused for an hour before taking her to doggy daycare. Wife had booked her in for daycare today because of the weather forecast – as we discovered yesterday it’s difficult to get her some good outdoors exercise when it’s cold and raining heavily. I couldn’t let her run around and get soaked in the rain, so I took her to the pet shop where she likes to roam up and down the aisles sniffing everything. And then we went to the daycare place, which is probably her favourite place in the world (besides home of course!). She gets to play with lots of other dogs and usually comes home exhausted. Here’s a photo the daycare people took of her with a friend:

Friyay at doggy daycare

I wrote more comics in the afternoon. Writing a batch of comics can take up to two days of work. I’ll have to finish this batch off tomorrow. That was basically it for the day. Writing comic scripts is the most time consuming part of making Irregular Webcomic!, because of periods of writer’s block, and other periods of doing research. For one strip I wrote today I spent a couple of hours researching the history of various Greek provinces during the Roman era, which included this tweeted appeal for assistance. (I found the answer.) You can probably guess what theme it was for. It’s amazing the amount of research I put into a simple gag comic strip sometimes.

This evening was a relaxing dinner out with wife and Scully at one of our favourite Indian restaurants. We walked up the street, with the rain thankfully just light, easing off for the night.

Rainy night at Crowie

New content today:

Lunch

It was supposed to rain today. The forecast was for 25 mm of rain, which is a lot. As it turned out, there was barely a spot, and much of the day was partly sunny. Even when it’s supposed to rain, it seems the weather is determined to keep Sydney dry.

I spent much of the day out, returning the lasers and diffraction slits I borrowed to the Sydney University Physics Department, and then having lunch with a friend nearby. Here’s the main Quadrangle at Sydney University:

Quad

We ate at The Pie Tin in Newtown, which has delicious meat pies (and vegetarian ones too). After having a savoury, I eyed the sweet pies. They had a cherry ripe pie, with bits of Cherry Ripe bars in it. Cherry Ripe is an Australian chocolate bar, and one of the most enduringly popular bars in the country. It’s made of cherries, coconut, and chocolate. So a cherry ripe pie sounds pretty good.

But next to the cherry ripe pie was a “cherry, chocolate, and coconut pie”. I kid you not. The exact same three ingredients. But it didn’t have bits of Cherry Ripe bar in it – it was just cherry, chocolate, and coconut. To be fair, the two pies looked very different, with the cherry ripe one appearing to have a lot more chocolate, while the other was more of a coconut cream topping. Anyway, I selected the less chocolatey one (as I’m trying not to eat too much chocolate), and it was very good.

Cherry chocolate coconut pie

I stopped off in the city on the way home to do a bit of shopping. Then this afternoon my wife and I took Scully for a walk and exercise at the dog park.

Um, and we watched the last of the first set of 10 episodes of Disenchantment. We were a bit behind on watching this series, but it turns out our timing is good, as the next series of episodes is released in September. So it’s been a bit of a wash as far as creating stuff today, but sometimes you just need a day off!

New content today:

Laser day

Today was my visit to the primary school to talk to the older classes about the solar system, and to supervise my Science Club class while we did experiments with laser diffraction. We measured the diffraction patterns of red, blue, and green laser light through double slits, replicating Young’s seminal experiment which established that light had the properties of waves. We ran out of time to do all of the calculations, but very quickly I got a rough figure of 620 nanometres for the wavelength of the red laser (which actually has a wavelength of 632.8 nm, so we got pretty close). Over the next while I’ll refine the measurements and calculate the other wavelengths too.

It was rainy today in Sydney. At least on the coast. It was dry as I drove towards the school, which is near the coast, and as I came down the hill from the plateau to the coastal strip, it began raining, and was really heavy by the time I got to the school. Unfortunately, we need the rain inland, where the dams are for our water supply.

New content today:

Cathedral framed

Winter blast

Today was cold and windy. It really felt like winter for once. I went out for lunch and the sky even had clouds in it! They were pretty thick and grey in fact, and I thought it might rain, but the promise of any precipitation turned out to be false.

Besides being a very warm winter, it’s also been extremely dry. We’ve had just 3 mm of rainfall so far this August, and Sydney’s average August rainfall is 80.3 mm. In July we had 43 mm of rain, mostly loaded into the first week, while the July average is 95.7 mm. So we’ve basically had 6 weeks with almost no rain at all. The news tonight reported that Sydney’s water supply dam level is now below 50% – the last time this happened was 15 years ago.

Besides the false promise of rain, the weather was pretty wild. I took Scully out to the dog park, and even though I rugged up in a jumper (sweater for the Americans) and a windproof jacket, it was still nastily cold with the wind blowing off the harbour. While there and chatting with some of the other dog owners, we heard a big crack, and we turned to see that a branch had fallen off the huge Moreton Bay fig tree that we were sitting/standing under (there are wooden benches there for sitting, which many of the owners do). Fortunately, it was on the far side of the tree, and didn’t land on any of us or our dogs. It landed on the street beside the park, narrowly missing someone’s parked car (lucky it didn’t land on that too).

A few of us dragged the branch off the street to clear it for traffic, and I took a photo. It’s not a huge branch, but would certainly have caused an injury if it had fallen on someone, or dented the roof or smashed the windscreen of a car. You can see it’s longer than a car, and it was fairly hefty.

Fallen branch

That’s Scully on the right, with the red doggy-jumper. Next to her is Monty, a chihuahua-Jack Russell cross. Up on the street is Scout, a west highland white terrier. As you can see, all the dogs are rugged up for the winter weather!

Also today I contacted Sydney University again to arrange to borrow some lasers and diffraction slits for my next visit to the school where I teach my Science Club class. We’re going to measure the wavelengths of different colours of light! I’ll go in tomorrow to pick them up.

New content today:

Olive oil flavour

This morning I had a blood test, and had to go to the pathology place while fasting, so couldn’t eat breakfast beforehand. I like breakfast. I don’t really understand those people who skip breakfast or who don’t feel any urge to have food until lunchtime. I wake up ravenous every morning and am hoeing into a bowl of cereal within about 5 minutes of getting out of bed every day. So having to wait until I walk up the street and wait for half an hour at the pathology centre is torture. Immediately after I left I raced to the nearest bakery to get something to eat.

Back home, I worked on writing annotations for the batch of Irregular Webcomic!s that I’d made over the past few days. This is the final step before publication, and can take most of a day, depending how much research I do and how much I write for each comic. But it’s a good feeling having the batch completed. And now it’s time to start thinking about writing the next batch…

I stayed in for lunch today and made myself bruschetta. I’m trying to use up a bottle of extra virgin olive oil that I got as a gift, before it passes its “best before” date. And also some caramelised balsamic vinegar.

It got me thinking about olive oil. We have extra virgin olive oil, for stuff like bruschetta and salads and those things that everyone says you should use extra virgin olive oil for, because it has a strong “fruity” flavour. And we have the “light tasting” olive oil that everyone says you should use for cooking, because it has a less strong flavour that won’t dominate a dish.

Now, I don’t know if it’s just me, but I can’t taste any difference whatsoever between “extra virgin” olive oil and “light tasting” olive oil. Not just the current brands we have either – I’ve never noticed any difference between any of the brands of either we’ve had over the years. I’m honestly beginning to think this whole “fruity” and “light” olive oil flavours are really just the Emperor’s New Clothes, and a way to make us all buy more olive oil because we “need” to have two different types. They all just taste equally bland and oily to me – none of them have anything that could remotely be called a “strong” flavour that might dominate anything else. Can anyone actually taste a difference between these olive oils?? Or even taste them at all??

And on another note, I took some photos of flowers. This winter in Sydney has been ridiculously warm. Besides flowers everywhere, there are new green shoots and leaves on many of the trees already as well. This is all at least a month early, possibly more. Take a look: magnolias, irises, lavender, azaleas.

Spring flowers in winter