Saturday, 25 February 2017

Are the trappist planets really similar to Earth?

A 5 minute video explaining why so-called "earth-like planets" discovered around Trappist-1 and elsewhere might not be anything like Earth.

http://www.bbc.com/earth/story/20170220-the-earth-like-planets-we-have-found-may-not-be-like-earth

Because these planets are orbiting very small stars, and hence have to be close in to be in the inhabitable zone, they will be tidally locked. So one side of the planet will be impossibly hot for any life, the other side impossibly cold.

We need to detect planets around bigger stars that are similar to our Sun. They won't be tidally locked, and any planet in the habitable zone, and which is the right size, has a faint possibility of being genuinely Earth-like. But we don't have the technology to detect such planets due to the glare of the star. We need more powerful telescopes and better technology.


Another link regarding these planets:


Could TRAPPIST-1 Be Home to a Galactic Alien Empire?

"Shostak says we should look for radio signals that can tell us if there’s possibly intelligent life on these planets".
Even if there is intelligent life, it's highly unlikely they'll have radio. Dolphins don't have radio. Humans only have had radio about 1/1000th of the time we've existed.

I reckon that planets that are genuinely similar to Earth will not be common, perhaps one in a million or perhaps even one in ten million? And perhaps only one in a thousand of them will have evolved a species that uses radio and has an advanced technological civilisation similar to ours. Most would be like Earth without humans.

Tuesday, 14 February 2017

The advantages and disadvantages of online grocery shopping

I live in England and I buy virtually all my groceries online now from either Tesco or Asda, and on the odd occasion, Sainsbury's. I thought I'd list the advantages and disadvantages of online grocery shopping as I perceive them.



The Advantages


1. There could be a greater range of groceries to choose from online. This though will vary depending on where one lives. I live in Louth in Lincolnshire in England. There's a moderately sized Co-op, a moderately sized Morrison's, and a large Aldi here. I can do online shopping at Waitrose, Tesco, Asda and Sainsbury's (but not Ocado or Morrison's or Iceland unfortunately). None of these four supermarkets are located in Louth and are at least 11 miles away from me. So if I specifically like any of their groceries, it is much more convenient to simply order online. But, in addition, the range of groceries I can purchase in these supermarkets online is somewhat greater than the 3 local supermarkets. So I think this is a significant advantage.



2. It is very easy to compare the costs. Let's suppose I want to buy milk chocolate. I can put milk chocolate in the search box, perhaps filter appropriately if the website of the supermarket allows it, and it will display all the milk chocolate bars I can buy. But, in addition, it will show the price per 100 grams. So it's easy to compare prices. Interestingly, at Tesco, I have found that the multipack of small bars of Cadbury's or Galaxy chocolate are often cheaper per 100g than the single large bars.


3. It's quick and convenient. Walking or even driving somewhere, and walking around the supermarket, and possibly waiting in queues, will take vastly more time than simply ordering from home. In addition, the delivery person is always happy to take your groceries into your home should you wish (although I just carry the groceries in myself).

4. It's easy to find things. You just put the name of the food item into the search box, and voila! The page fills up with the appropriate food items. In the actual store I sometimes have to search quite a bit before finding what I'm looking for. It doesn't help that they periodically move the groceries around (this is so you'll see food items that you don't normally see. You might then buy that food item. However, it's inconvenient for the customer!).


5. The delivery charge is ridiculously cheap. I just pay a £1 every time. It's true you can pay up to £6 for weekend mornings. But why not just choose an evening on a weekday for delivery when it's often just £1?



The Disadvantages


1. The freshness of the food. First of all here is an interesting quote from another website:


The last thing that a grocery store wants is dissatisfied customers complaining about having received poor quality goods. This makes a lot of extra and unnecessary work for their customer complaints department. It is therefore good practice for them to only send the freshest produce out on the home delivery orders. A reputable store will give a guarantee that if you are not happy with your delivery then they will give you a refund.



The first sentence is nonsense. In my experience -- and indeed of other people I have read on the net -- the 'best before' dates and, more crucially, the 'use by' dates, leave a lot to be desired. If I'm actually visiting a supermarket I avoid the perishable food items at the front of the shelf and get one from the back as these normally have better 'use by' dates. But, when you buy online, it would seem the pickers of your groceries don't do this. On odd occasions I even end up getting delivered groceries that include perishable foods which have a 'use by' date that is the same date they are delivered! Since the supermarkets will have difficulty in selling these items to the customers who actually come into their store, I suspect that they deliberately deliver these perishable groceries that are close to their 'use by' dates to their online customers so they can make more money. Otherwise, they would need to sell them off cheaply to get rid of them quickly.


It's true you can refuse any of the items that are delivered. But, in practice, in order not to detain the delivery person, I tend to be in too much of a hurry putting all the groceries into bags to have time to examine the dates on the fresh food. If the 'use by' date is particular bad, like the very date they are delivered, you can telephone or contact the supermarket via a webform, and they will agree to refund you for the relevant item and you get to keep the item. This is a bit of a chew though. And I imagine the majority of people will not complain, and the supermarkets will be aware of this. So, contrary to the quoted website, it is still profitable for them to deliver fresh food with the poorest 'use by' dates to their online customers.


It can be particularly irksome if I'm buying some essential fresh product like milk. I can buy 4 pints for £1, or alternatively 2 pints for 75p from Tesco. Visiting a supermarket I can easily buy fresh milk whose use by date is 12 days ahead. I live by myself, but in 12 days, or not much longer, I can get through 4 pints. But when buying milk online, sometimes the use 'by date' is as little as 5 days ahead, which is not sufficient time for me to drink 4 pints. So should I order the 4 pints, or pay over the odds and buy 2 pints of milk? It's a bit of a gamble! The bottom line though is that I often end up throwing out food which I wouldn't do if I went into the supermarket itself to buy my groceries. Even if I am refunded, it's a waste of food.


I should state that in the past, unlike Tesco and Asda, Sainsbury's 'use by' and 'best before' dates were fine. However, since their delivery charges were reduced and are now more or less in line with the delivery charges of Tesco and Asda (as little as £1), I think Sainsbury's 'use by' and best before dates have gotten poorer. Also Sainsbury's range is not as extensive as Tesco's or Asda's.

2. Just because an item is apparently available on the website, most emphatically doesn't mean that you will actually get it delivered. Sometimes . . nay . .
 often they run out of stock. This is normally those groceries which I assume they tend to sell less of e.g. organic and free range food, tandoori flavoured chicken etc. And also for those groceries that are on a genuine special offer. But, often I have only shopped at the supermarket in question since it apparently selling specific groceries, or there is a special offer on a particular food item I'm interested in -- precisely those groceries which they are quite likely not to have in stock. It would be vastly more convenient if I knew upfront which groceries they actually have in stock. Because if they don't have the relevant item in, then frequently I wouldn't have bothered ordering and would have shopped at a different supermarket, or not bothered ordering on that occasion at all.

Now, it might be thought that I could easily ring up the number on the website and find out if they have a particular item in stock. I have tried that. At Asda for 3 boxes of becks, each containing 15*275ml bottles of becks for the special price of £20 (they cost £8 to buy for a single box). I imagined the conversation would be something like me asking if they have these boxes of 15 bottles in stock for the Supermarket that delivers to me in Louth, the customer service person saying "hold on sir for 1 minute, I'll just check", that person looking on some database, then responding literally around a minute later with the response of yes or no, and if no when they would expect them in stock.

But no, it was nothing like that . . nothing like that at all. First of all I got put through to someone with a strong Indian accent whom I could scarcely understand at all. I didn't think that would be too bad since they normally seem to understand me OK, if not me them. I think I can distinguish them saying yes or no. But, things didn't pan out as I anticipated. He asked an apparent endless stream of questions, such as the code on the product, which supermarket delivers to me and other questions that I continually had to ask him to repeat since I had such difficulty understanding him. I kept saying, look it's just the standard sized bottles of becks, I just want to know if they have any boxes of 15 in. Can you not ring the appropriate store up and ask them?? Eventually, after he asked yet another question which I couldn't hear, no matter how often he repeated it, I simply put the phone down!

So it's impossible to find out what they have in stock, at least at Asda (and I suspect other supermarkets too), you just have to order and hope for the best. And, since the order normally has to be at least £40, I'm disinclined to order another £40 of groceries in the following few days on the off chance they'll have restocked the relevant item. Moreover, even if I did, it's quite likely they still
 won't have it in. And some items are rarely available. Over the past 6 months I've ordered fresh tandoori chicken thighs from Asda perhaps around 8 times, but they have only been delivered twice, despite always being advertised as available on their website.

The supermarkets do deliver substitutes, but rarely do I find them satisfactory. For example, I've ordered cod loin before that was on special offer. They didn't have any left. I would have expected to be substituted standard fresh cod, or failing that fresh haddock, or maybe even frozen cod. No, I got substituted farmed
salmon! (I never eat farmed salmon because of the health issues, I only eat wild salmon). Another time I had ordered haddock fillet fish fingers, but they substituted frozen sausages! I've ordered John West tins of red salmon when they have been on special offer. What was their substitute? Not Princess tins of red salmon which you might expect, but tins of John West pink salmon! Why? Well, I suspect because the tins of pink salmon were roughly the same price as the discounted John West red salmon, where as the Princes red salmon, not being on special offer, was around double the price. They ain't gonna lose out by giving me the Princes! I've ordered 760g porridge oats for £4, and they've substituted 648g for £4.88 i.e they've charged more and given me less! And the number of times they don't have fresh haddock and gave me cod in its place you wouldn't believe. Are the oceans heaving with cod or something?
 
3. I tend to search out those groceries that at a particular time cost less than the they do on the other supermarket sites. Sometimes they're on special offer and have a date when the price will go up. But often they don't. Now, when you buy groceries online from a supermarket, you don't pay the price they are on the day you order, but rather the day they are delivered (normally the next day in my case). For example, on one occasion I ordered 16 cans of fanta zero for £5 at Asda (December 2012). These were not claimed to be on special offer, and no date was given that specified they would go up in price at a certain date. When they were delivered the following day I got charged £8.96 for them; they had increased in price by 79.2% in the space of 24 hours. No warning was given to me that they had increased in price. The same thing happens at Tesco. For example in June 2015 I'd ordered 15 bottles of becks (in a box) for £7.50. That was good value and wasn't on "special offer". But the next day when delivered it had gone up to £10! (As a matter of interest, on the relevant Tesco page the Becks had not only increased in price by 33%, but had a message saying “Now Cheaper”. Surely, since it had increased in price by a whopping 33% in 24 hours, the message should have said “Now Vastly more Expensive” instead??).

4. You miss out on the social aspect of shopping. You might bump into friends or neighbours or people you recognise from the pub.

So these are the advantages and disadvantages of shopping for groceries online. I still think the advantages outweigh the disadvantages, especially with where I live since there's a much greater range of groceries to choose from if I order online compared to the local supermarkets.

The myths and traditions of death

 An interesting Guardian article : It is worth reminding ourselves that the vast majority of our ancestors saw the world in a very different...