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23 May 2019 – Neutristors

New Atlas reports: Neutron generators provide materials analysis and non-destructive testing tools to many industries, including oilfield operations, heavy mechanical production, art conservancy, detective work, and medicine. Many of these applications have been limited by the rather large size of current industrial and medical neutron sources. Now Sandia National Laboratories (SNL) ... has invented a new approach toward building tiny neutron generators called neutristors.

The neutristor is a small solid-state device which uses deuterium-deuterium fusion to produce a stable helium-3 atom and a neutron. The devices thus contain no radioactive substances.

D + D → n + ³He

Devices already exist which allow the production of neutrons on demand without radioactive iostopes of heavy elements, but they are "big and clunky" compared with the new devices, and cost hundreds of thousands of dollars. I thus believe this is a very significant step in the development of new nuclear technologies, of similar importance to replacing valves with transistors. Estimated production cost is US$2,000. See this video for more information.

15 May 2019 – Plastic in the ocean

An incredible 10% of the oxygen in the atmosphere is produced by a type of bacteria that was only discovered 30 years ago, and it turns out chemicals leaching out of plastic can significantly affect how well the bacteria can do stuff, as explained in this article: The results were striking with the chemicals impairing the Prochlorococcus' growth, reducing its ability to photosynthesize, and altering the expression of a large number of its genes.

The tests were performed in a laboratory and with the limited amount of research presently done on the subject it's very difficult to know how the chemicals actually affect these bacteria in the ocean, but it does look like it's one more way we're polluting our planet.

21 March 2019 – Gun laws change

Prime Minister Jacinda Ardern has announced changes to our gun laws banning military-style semi-automatic weapons and assault rifles. As of 3pm, they cannot be owned with an ordinary A category licence. The decision has been noted all around the world.

"This is what real action to stop gun violence looks like" – US Senator Bernie Sanders.

This guy sounds like he "gets" New Zealand:

USA 6 yrs after Sandy Hook
•Thoughts & prayers

New Zealand 6 days after Christchurch
•Ban semi automatic assault weapons
•Buyback program
•Pay for all funerals
•Provide income for harmed
•Māori dance
•Wear solidarity scarf
•AND Thoughts & prayers

– Qasim Rashid, Esq, attorney, candidate for the US Senate in the state of Virginia.

27 February 2019 – Mini Lava Cave Exhibition

A mini version of the very popular Into The Underworld lava cave exhibition is returning, this time to Cornwall Park. A subset of the stunning illuminated lava cave images shown at Silo 6 (twice!) will be displayed in Huia Lodge from 9 March to 7 April 2019, open 10 am to 4 pm 2019.

Huia Lodge is open 10 am to 4 pm daily. For more information see cornwallpark.co.nz/whats-on/exhibition-intotheunderworld.

11 February 2019 – Heroic Garden Festival

The Heroic Garden Festival is on this coming weekend, 16-17 Feb. There are a whole lot of interesting gardens across Auckland that can be visited, and even one garden that features a cave.

I'll be keeping cool in the cave for some of the weekend, explaining to visitors how lava caves form and how many there are around Auckland. Buy a ticket, support Mercy Hospice, and descend into the Underworld!

5 February 2019 – Magnetic north pole on the move

Since 1831 when the magnetic north pole was first located in northern Canada, it has been on the move northward. It's been a slow journey, and in the mid 1900s it was only moving at about 11 km per year. However, in the last decade or so the rate at which it's moving has greatly increased, and it's now racing at about 55 km per year. That's fast enough that a new World Magnetic Model has just been released, a year earlier than its normal five-yearly update.

To make it more interesting, no one is quite sure why it's happening. One idea is that there are two magnetic field patches – one in northern Canada and one in northern Russia – that vie with each other to determine the location of the north magnetic pole. The Canadian patch has apparently recently been getting weaker, meaning the resulting magnetic pole position is heading quickly toward Russia, and crossed the international dateline at the end of 2017. To make it even more interesting, the location of the south magnetic pole has not moved much at all. See this National Geographic article for more info.

To be clear, the "north" in what I've been calling the north magnetic pole is a geographic reference, and magnetically it's actually a south magnetic pole. That's why the north end of a compass needle (the pointy end) is attracted to it.

18 January 2019 – Booking being taken

Another year beginning, and all the things to do that come with it. I'm accepting bookings, so now would be a good time to make enquiries about tutoring for 2019.

23 November 2018 – Solid state heavier than air flight

A team from MIT (the USA one) has claimed to have made a glider which can sustain powered flight without any moving parts. It uses "lifter" technology, which has been around since around 1920 but which hadn't before been successfully scaled up, since it produces lift of only about one to ten grams per watt. Lifters are normally run tethered in order to supply power.

There's a video of the test flights which explains a little about how it works, but it includes more crashes than successful flights. Sadly there's no known way to make the technology more efficient, so this event is unlikely to be as significant as the first heavier-than-air powered flight.

20 September 2018 – Into The Underworld

Into The Underworld is back on! An exhibition of laser scanned images of Auckland's lava caves held in Silo 6 in Wynyard Quarter, Into the Underworld (www.intotheunderworld.nz) gives a unique view of Auckland's volcanic heritage, and shows just how close our lava caves are to suburbia.

The images themselves are stunning, with some up to five metres tall, and others up to seven metres wide. The exhibition is open daily noon to 9pm and runs until Monday 1 October 2018.

6 September 2018 – Acetylene

When using acetylene it's really important to know what you can and cannot do. Acetylene is a flammable gas – indeed, known for its particularly hot flame – and like many flammable gases it's dangerously explosive at the right combination with air (or with pure oxygen). That last bit is really important... and basic science. It means acetylene has to be stored and used carefully.

Acetylene also has the interesting property that if you pressurise it to about 2 atm it can spontaneously explode, decomposing into other stuff like hydrogen and carbon. To avoid that happening, acetylene cylinders contain acetone, a liquid in which the acetylene dissolves. Copper catalyses this reaction, so copper and brass fittings should not be used. The cylinders need to be used vertically so the acetone does not come out.

This is pretty straight forward stuff, but on Monday 3 September two people missed applying the simple science and a father of three children died. The NZ Herald detailed (warning, graphic details) how it happened: a guy put acetylene and oxygen together in an LPG cylinder and his friend didn't stop him from going back to it.

In July 2017 I talked about how a lack of basic science knowledge caused the deaths of 15 people from a cornflour fireball. As I said at the time, science enriches lives, broadens horizons, and can save lives.

11 July 2018 – Wild Boars Coach

With monsoon rain from May to October it's a fair question to ask why the coach Ekapol Chantawong took the team into the cave at that time of year. We should consider several points to put this question in perspective.

Two signs outside the cave says it's closed July to November due to flooding (calling July to Nov the "flooding season"), which doesn't actually give any reason for the coach to think it wasn't safe on 23 June. There are guided tours through the first kilometre from November to June, which again gives no reason to think it is unsafe in June.

A local points out that the cave is "a magnet for teen adventurers". A trip to the cave was thus ideal for a team-building experience. It wasn't the team's first trip to the cave, so it clearly served the purpose the previous time, two years ago. (I don't know what time of year the previous visit was.)

Yes, it turned out to be the wrong decision, but that's really only clear in hindsight. Yes, he should have told the senior coach where they were going.

However, I think it's more important to look at what Ekapol Chantawong contributed to the survival of the team. Not only were the boys alive when found, they were alert and mobile, and calm.* From his own tragic history, and years of spiritual training, it seems that he was the perfect man for the job. He lived for the team is his life, and it could be argued they lived for him in the cave.

11 July 2018 – Wild Boars all safely out

In an incredible rescue effort involving thousands of people the whole 12 members of the Thai football team and their coach are safely out of the cave, along with all the rescuers. The selflessness shown by the more than 130 divers, the other rescuers, and the up to ten thousand volunteers working behind the scenes is truely inspiring. From an initial situation that seemed like a Schrödinger's cat situation, this is an extraordinarily good result.

The sad death of former Thai navy diver Saman Kunan was a sobering reminder how dangerous the work was, but the mission to evacuate the team was brilliantly planned and prepared for, and executed flawlessly over the three days it took to swim, walk, and carry the Wild Boars out.

Also sad is the death of the father of Richard Harris, the cave-diving Australian anaesthetist, on Tuesday a short time after the rescue was completed.

Those interested in learning more about caves might like to contact a local caving club, such as Auckland Speleo Group.

9 May 2018 – Term 2

My schedule is pretty full now, with just a few slots available. I may not be able to find a time that will suit, but you're welcome to ask.

Enquiries for one-off holiday sessions for the end of term 2 are welcome.

11 April 2018 – Power Cuts (updated)

The storm that raged last night has taken its toll. The Homeschool Science Fair that would have been this morning was cancelled postponed until Wed 2 May due to no electricity at the Fickling Centre, which also meant no access.

What's more, according to the Vector power cut location cellphone app, up to 10 11 12 of my present students and as many as 14 16 17 24 27 of my former students are (or have been) without power. They are due to have it restored between midday today (Wednesday) and 6pm tomorrow midday Friday 10pm Saturday. I hope they all stay warm and dry.

I found bits of corrugated plastic scattered around five properties this morning. Close examination shows they were part of a roof, but I haven't found where the roof was or why it (apparently) exploded.

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