Friday, 13 March 2020

Okay, I thought I'd put my tuppence forwards on the current Covid-19 crisis, and the decisions that the government have to make. I am not an expert; I have no particular knowledge on medical matters or pandemics - so I'm in the same boat as most of us!

Feel free to disagree, but these are my current thoughts, and please forgive the length:

1) We are working on incomplete data, and are having to make decisions based on assumptions. This is always risky. Just a relatively small change in one piece of data might invalidate one approach, whilst validating another. For instance, if a working vaccine is not developed before the end of the year, then isolating everyone now becomes a less valid approach. If a working vaccine is developed by mid-year, then isolating everyone now makes more sense.

Likewise, the number of asymptomatic cases (that means, the people who get Covid and are not recognised as such because they don't get major symptoms) is important. As we don't have a reliable mass antibody test yet, this is a major unknown that again has a major effect on the decision made. If there are a small percentage of asymptomatic cases, then isolating now makes more sense than if there is a high percentage.

Experts and politicians can look at the data and come up with different conclusions. Reasonable people can reasonably differ, especially in the presence of uncertain data.

2) Every country is different: in their stage of the epidemic, the way it is progressing, and in their social mores. In some countries, the epidemic is in only one or two regions, and therefore the rules applied to those regions can be specialised. Here in the UK, we do not have particular hotspots, and no reason to believe it can be contained in particular areas or regions of the country. Likewise, we do not live in a state where (allegedly) doors to apartments can be welded shut to keep them from leaving. We appear to be a week or two behind other countries in the outbreak; what works for them now might not work for us, now; it (or another approach) may work for us in a week.

Blindly comparing our decisions to those of other countries without factoring in such differences is, at best, pointless. This is not about some Union Jack-waving British exceptionalism; it's about the reality that our situation differs - as does every country's.

3) There might not be a 'right' way to handle this. There is a good chance that no approach is perfect, and that even when the current situation has died down, we won't know what the 'right' thing to do was. We are living through a massive experiment.

4) What is 'obvious' is often non-obvious. A common call is for schools to be closed, as has been done in other countries. Yet that can have side effects: children (who, unlike the 1918 flu pandemic, appear to be least affected by the illness) have to be cared for, and that burden will often fall on grandparents - who are most affected. Likewise, Madrid has had to lock shut the gates to playgrounds, as children were just meeting up there instead. What happens with exams? Coursework? A 'simple' decision has massive consequences - and not all in one direction.

5) I'm very glad I'm not the one who has to make these decisions.

In the UK's case, I don't see any reason to believe that Boris Johnson, the government, the Chief Medical Officer, the Chief Science Adviser et al *want* this awful disease to spread and for lots of people to die. They're having to use incomplete data to come to a decision in a terrible situation. I hope they've made a good one.

6) Finally: much of this is up to individuals. If you want to keep you and yours well, don't be silly, and follow the advice. Bulk-buying toilet roll is of little use. Wash your hands. Avoid touching your face. If you feel unwell, rest and isolate yourself as much as possible.

Help your relatives. Help your friends. Help your neighbours.

Wednesday, 4 March 2020

Chris Packham

Apparently Chris Packham is launching a judicial review of HS2, saying it does not take carbon emission targets into account.

https://www.bbc.co.uk/news/business-51722251

Which I found slightly odd, because a little blip in my memory recalled something. So I look on his website, and find nothing under the 'travel' link:
https://www.chrispackham.co.uk/category/travel-with-chris-packham

However the wonderful Wayback machine shows the following:
https://web.archive.org/web/20191214183301/https://www.chrispackham.co.uk/category/travel-with-chris-packham

So Chris Packham feels it's perfectly fine to make money out of taking adoring fans on trips to Alaska, Antarctica, the Gambia, Kenya etc - which of course involve environmentally-harmful flights  to and from the ships or locations - but does not want the hoi polloi in the UK to be able to travel.

He also says 'Bakotu Hotel – the base for my first tour – is my second home.' How nice it must be for him to have a second home in the Gambia. I bet he walks there ...

Wednesday, 31 July 2019

RED month, July 2019

On July 1st, I set out to do an early morning run. A task I repeated the next day, and the next. This morning I completed my 31st run of July, and I had Run Every Day.

So, the stats: I ran 176 miles in the month, or an average of 5.89 miles per day (and yes, I wish I could have made that up to a round 6). I spent a smidgen under 32 hours running, and ran at a rather pedestrian 5.5 MPH average (more of a jog, really). My total ascent was 488 metres - a consequence of living in rather flat Cambridgeshire. My earliest start time was 04.20, my latest 09.20. All bar three runs were started before six in the morning, so I could get home and showered before Sencan left for work.

The most I'd ever run before was 10K runs on 10 consecutive days, so it feels good to have somewhat smashed that. I exceeded my target distance on every run.

The lessons are numerous. After about the fifth day, I gave up on trying to go fast, as it only meant I'd go slower the next day. Recovery time is important for speed, and running every day does not allow for recovery time. I hate doing stretches. Running in light rain in summer is very pleasant. Seeing the sun rise is always uplifting. Running up slight gradients is wonderful. A 15km (9 mile) run is harder than a 20-mile walk with backpack. Running sans shirt is wonderful in warm weather, although alarming for anyone who sees a hairy bear running towards them!

I have suffered some chaffing on my inner thighs and, rather embarrassingly for a man, one sore nipple that was cured by liberal applications of vaseline that caused my running shirt to appear as though I was lactating. My knees are surprisingly fine, and my bad ankle only gave me trouble on a couple of occasions. I am very tired, but have lost over 5kg in weight.

The worst thing is:

I hate running!

And I shall get up tomorrow and run again. But I might take a day off after that. Or not ...

Thursday, 16 May 2019

Blue Moon


Yesterday, Jeff Bezos (of Amazon fame) gave an hour-long presentation about his views on the future of mankind and space. This might seem like an odd topic for the world's richest man, except for the fact he is investing a billion dollars of his own money into a space company, Blue Origin.

The presentation is well worth watching in full:





Some thoughts on the presentation:

The presentation was slick and well-done. Bezos comes across as very knowledgeable about the topic: which is slightly surprising given the number of hats he wears. His presentation skills are good (at least when compared to the sometimes-stuttering Elon Musk).

We are not the intended audience for the presentation; Bezos was trying to talk directly to the movers and shakers in the US government. The Trump administration want to get Americans back to the Moon before the end of a possible second term in office, and Bezos wanted them to know that they have a system under development that could fit directly into their current plans.

The presentation had four broad sections:
  • Define the problem: mankind's resource and energy usage is increasing. Unless something changes, this means eventually they will have to be rationed.
  • Define a vision of the solution: take mankind off the Earth via things such as O'Neill cylinders and the use of in-space resources to replace Earthbound primary industries.
  • Define the strategy: build the infrastructure that will allow others to fulfil that vision.
  • Define the tactics: initially, rockets such as New Glenn and the Blue Moon lander.
The first three sections all seemed logical: you can argue for other solutions, but his vision encompasses one possible solution. He is also willing to put vast sums of his own money towards the first steps in securing his vision.

The highlight of the presentation was the unveiling of the Blue Moon lunar lander (see https://www.blueorigin.com/blue-moon). This was impressive. They had obviously thought deeply about the details: from high-bandwidth laser communications, to the landing angle (i.e. platform stability) of 15 degrees; to using lifeboat-style davits to unload from the cargo platform on the top, to looking at landing accuracy and the issues caused by the debris from the rocket blast on landing. 
Bezos also unveiled a new liquid hydrogen / liquid oxygen (hydrolox) engine, the BE-7. rIn this section, Bezos mentioned that the technology of both the engine and the Blue Moon lander were direct consequences of the New Shepard sub-orbital craft that his company is current;ly developing, and which they hope will take tourists to the edge of space later this year.

This explains many of the criticisms that the New Shepard system gets: it is part of a plan to gain liquid hydrogen and vertical landing experience. Personally, I had been expecting them to use the existing BE3 engine (used in New Shepard) for their Moon lander, or to use another company (e.g. Masten and something based on Xeus technology - see https://www.masten.aero/xeus).

The modularity of the Blue Moon system is slightly reminiscent of the Apollo Lander. This was expanded slightly for the J-class missions (Apollo 15,16 and 17), but much larger enhancements were proposed under the 'Apollo Extensions System' - for instance to create a long-stay lunar shelter (see http://www.astronautix.com/a/aeslunarbase.html). These developments sadly never occurred because the program was cancelled.

They are partnering with others for payloads, something I see as a positive and in line with his strategy. I also like the fact they've formed a science advisory board, and the 'kids club' could be either a damp squib or an inspired move - depending on how much effort they put into it.

Some minor criticisms

  • It would have been good to mention SpaceX wrt vertical landing, and perhaps even congratulate them, whilst specifying the differences in their vision, goals and strategy. I can understand why they did not, but the elephant in the room is too large to ignore.
  • New Glenn is not fully reusable; only the first stage is. This was glossed over in the discussions wrt cost.
  • It would have seemed good to thank and congratulate NASA. Both SpaceX and Blue Origin are building on science done by NASA before, during and after the Apollo landings: this would be unachievable without that science and the general infrastructure.
  • The Blue Moon mock-up showed on stage was for an unmanned craft, and yet he also showed a picture of an enhanced, crewed version. In my view it is doubtful that a crewed version will be ready for 2024.
  • Liquid hydrogen is nasty stuff, and it took NASA and various militaries years to understand how to handle it reliably. Blue Origin have developed good knowledge on this through their New Shepard rocket, but keeping liquid hydrogen liquid in space and avoiding boil-off is *really* difficult. Although he somewhat addressed this in the talk, it is IMV the biggest issue facing the project.

Conclusions

Can Blue Origin get a large lander to the Moon in five years? It's tight, but probably. Can they get a crewed lander onto the Moon in five years? That is *much* tighter, and I'd give them only a 20% chance of that (figure plucked out of the air).

The fact they've had the BE-7 engine under development for three years shows they're looking at the problems, and are developing solutions out of public view. That might even extend to other problems I foresee, for instance EVA-capable spacesuits or life support - one billion dollars a year buys a lot of skunkworks.

The Blue Moon lander seems utterly (almost boringly) feasible. liquid hydrogen storage issues aside.

Good luck to them.



Monday, 8 April 2019

The Venezuelan Petro.

In February 2018, the government of Venezuela - well known for its financial acumen - announced they were jumping on a digital bandwagon by launching their own cryptocurrency the Petro. The new currency had many stated aims, including to bolster the crashing Venezualan Bolivar currency, and to circumvent US sanctions.

This was an interesting move. The  initial sale allegedly raised $3.3 billion for the Maduro government, although there has been no independent verification of that claim.

I personally feel that government-backed cryptocurrencies are a good way forward for the technology. Although governmental backing reduces some of the advantages of such systems, it also gives a currency increased trust - and trust has been one thing holding cryptocurrencies back.

It is therefore interesting that Venezuela, a country that is in the depths of a massive financial and political crisis, is the first country to make such a move. So what has happened in the last year?

The answer appears to be 'not much'. You cannot go onto a market and buy a Petro or Petro Gold. No-one seems to have an idea about the value of a Petro. To make matters worse, the technology behind the Petro has changed several times of the year, even after launch - and there are even doubts that the currency even exists in any practical form.

I won't go into any jokes about the failure of a socialist state to create a reliable currency - after all, we capitalist countries haven't been brilliant at that, either. But the Petro does seem to be yet another scam cryptocurrency - albeit one created by a government that is in real trouble.

And meanwhile ordinary Venezuelans suffer.

Saturday, 6 April 2019

6 April 2019 - it's GPS rollover day!

Today is a special day! You could be the lucky recipient of a rollover!

No, not a lottery win, but something even more unusual: the 1,024-week GPS week-number rollover! Stay tuned to see if you are a winner!

Okay, time to be serious. Twenty years ago the news was full of the upcoming Millennium  Bug, where ancient (and sometimes recent) computer systems that used two digits to represent dates - e.g. '99' for 1999, would roll over and start using '00' for 2000 - which causes all sorts of problems when you perform operations on the data and 2000 is seen as being before 1999.

Fortunately many good engineers  worked for years to ensure that the effects of the Millennium Bug were not as bad as some forecast. Some say that this means the Bug was overwrought nonsense: in fact, problems were avoided because people did lots of work to prevent those problems.

The Millennium bug was an epoch event: dates and times in computer systems have to be represented by numbers, and those numbers are of finite size. The larger the number, and the larger the granularity each number represents, the greater the length of time the number can represent.

Another example is GPS,which has exploded in popularity over the last twenty years. Most cars now have GPS receivers, they are in all smartphones, and many of us even have receivers in our wristwatches. Many vital system require timing and positional information from GPS. Yet GPS receivers also have an epoch - in this case, the data sent from the satellites to the receiver uses 10 bits to represent the week, allowing 1024 distinct values. This means that every 1024 weeks, it resets. If for some reason it gets the 'wrong' week, the receiver may start giving incorrect data to the user.

Today, the 6th of April, the week number rolls over. It is not the first time it has happened (it last happened on August 21st 1999. There were far fewer receivers back then (in fact, is it about the time I got my first Magellan handheld GPS), and the problems were not as significant.

However today it may be different: manufacturers will have been aware of this issue, and will have  put some protections in place. However if your receiver is over a decade old, and has not had its firmware updated, then there might be problems.

The good news is that the GPS constellation is being updated, and the new signals have a 13-bit week, enough for 8,192 weeks - or 157 years. I doubt a rollover of those new signals will affect me much!

But if you have an older receiver, I hope you don't win the GPS rollover lottery!

Thursday, 4 April 2019

Brexit and Julian May

In the 1980s and 1990s, the late Julian May wrote a series of eight books: the four Pliocene Exile books, the standalone vinculum 'Intervention', and the three novels of the Galactic Milieu trilogy.

In them, she describe a world where alien races have come to Earth whilst we were on the brink of nuclear war and offered us the stars. Since then, mankind has moved out from Earth to planets around the Galaxy: the large nations have many worlds, the smaller a few, and the smallest share some. Vast liners travel the ether between worlds, and mankind is flourishing.

Yet there are discontents. Humans - often powerful and influential ones - who rail against the aliens with whom we share control. We once controlled the world, but we are now a small piece of a gigantic Galactic cog. We should be in charge.

So these discontents start a rebellion that destroys worlds and kills billions. It is a pointless rebellion: one where they shake their fists at the very beings who have treated us well.

And it ends with Humanity chastened and still part of the Milieu. Little has changed, for the course was inevitable, and changing it would destroy everything.

And that is now what might happen to Brexit. We in the UK have a history that is littered with glory, and it is easy to sit back and want those glories to return. Britannia ruled the waves, and we ruled the world. But that world has changed: first came America, and then other countries overtook us. We are a small country: proud and brilliant, but small - in a world where size matters.

In such a world, is the EU an inevitability?

So we have a choice: to join up with other small countries (and smaller ones) to form a bloc that has more power together, or to be small and alone. It seems that the former might be inevitable. If so, perhaps the wettest of wet dreams of hardcore Europhiles are correct and, like Humanity after the rebellion, we will eventually become leaders of the group.

If so, then Brexit may be, like the rebellion in the books, a felix culpa - a blessed fall.