I got let out of work early today as it's Christmas Eve, so I'm now home and ready to start the holiday properly. One of my neighbours has invited me over for a drink a bit later, so that's going to get things off to a good start.

A lot of my friends and family are away over Christmas: one of my brothers is staying with his wife's parents in Louisiana, Rebecca and the twins are off in East Anglia. It will cut down the number of hours I spend on Internet Messaging programs to an amazing degree. Rob has installed Skype, which we were playing about with this week (a very nifty piece of software) and as I was still running version 2.0 I upgraded mine as well. Now all I have to do is persuade Ruth and her mum to install it on their machines as well. And Sallie too, when she gets her machine fixed.

But in the meantime, I need to finish wrapping up presents rather than sitting here at the computer. I have quite a few deliveries to make over the coming week. Wherever you are, whatever you're doing, I hope you have a very festive festive season.

Apparently, Chuck Norris's tears don't cure cancer after all, and he's had enough of claims to the contrary. You know, there are days when the news just comes over all weird, and it looks like today is going to be one of them.

It was the winter solstice at 6:07am this morning - so the days will start to get longer again. Thank goodness: the sun sets here at 4 in the afternoon, so we don't get to see much of it at this time of year. However, right now there's sunlight streaming in through the window. It's the first time the fog and gloom has lifted for almost a week, and at last the temperature outside is creeping above zero.

When I came out of the village Post Office this morning there was a very annoyed herring gull screaming at something or other in a tree by the road. As I watched, there was an explosion of wings and a rather disgruntled buzzard flapped off in search of somewhere quieter. It was a lovely sight. I see them flying over the village quite regularly, but this was the first one I've spotted sitting in someone's garden.

As if to underline the point I made yesterday about the same subject cropping up over and over again, the LA Times is carrying a story about a possible Tunguska-sized impact that could happen on January 30th next year. This time, NASA's NEO team are really hoping the impact will occur, because it means they can study it closely. And they're not worried about the risk to humans, because this asteroid won't be hitting Earth. It's heading towards Mars. If the asteroid hits, it is likely to leave a crater about the size of the Barringer Crater in Arizona.

At present, the team reckons there's a one in 75 chance of an impact, but they won't know for sure for another couple of weeks or so because the rock is behind the Moon at the moment and they can't track it (and that's another reason why that Venus-equivalent orbit tracker would be a bloody good idea, right there.)

Stay tuned, and when I hear more I'll post it here.

It's funny how from time to time a subject that you haven't read about for ages suddenly crops up in several stories over the space of a week. After my recent musing about asteroid impacts I opened the New Scientist magazine last night and noticed a story about work being done at Sandia Laboratories in the United States. Mark Boslough has run a computer simulation which indicates that the devastation caused by the Tunguska event could have been caused by a 5 megaton airburst. This is a quarter the size of the explosion that was previously thought to be necessary, and he's calculated that it could have been caused by an asteroid as small as 50 metres across disintegrating as it hit Earth's atmosphere. Despite the reduction in size, Boslough has a sobering observation: "If one of these events hit an area of high population density, it could kill one million people."

If this wasn't worrying enough, at the moment NASA's Near Earth Object (NEO) program only tracks objects bigger than 140 metres across or so as they shoot across the Solar System. In fact, the NEO program's goal is to detect 90% of the Potentially Hazardous Objects (PHOs) that are more than 140 metres across and which pass within 0.05AU of the Earth's orbit (that's about four and a half million miles). That's all they can afford to do with the money available. That already leaves a rather large amount of wiggle room for unexpected arrivals, but it should be pretty obvious that the distribution of asteroids up there in space means that there are lots more 50-metre rocks out there than there are 140-metre ones.

In other words, Tunguska-scale events are more likely to happen than we previously thought. And if another one is heading our way, we're not likely to know anything about it until it happens. NASA would like to have a dedicated NEO sensor running in a Venus-like orbit to help out with identifying potential threats, because it's very difficult to detect anything that's heading towards us from the general direction of the sun. However, no budget for this project has been allocated at all.

I think they ought to get the money to make it happen, don't you?

Well, I know what *I* want for Christmas: my own nuclear reactor. As reported on Slashdot, Toshiba have announced one that'll run for forty years or so putting out 200 kilowatt hours, and it'll fit in my garage. Okay, so it uses liquid lithium-6 to absorb neutrons, so there might be one or two environmental concerns, but that's just being pickym right?

Tom points out that when it comes to enthusiastic reviews, Amazon.com's page on The Best of David Hasselhoff beats them all, with over a thousand contributions. Who said Americans don't understand irony?

It's about 2° C outside and I'm sitting here shivering despite the fact that I'm wearing a fleece and I've got the heating on. The forecast for the UK over the next few days is for cold, gloomy weather (although the sun is trying to come out right now) so I am still thinking about getting one of those special lamps to combat SAD.

The science fiction author Sir Arthur C Clarke is 90 today.

I don't often get sucked in to these new-fangled marketing campaigns, but I have to say that the way J.J. Abram's movie Cloverfield is being presented makes it one of those films that I really want to see, and see now. Unfortunately, all I can watch at the moment is what appears to be the first five minutes or so, but I'm a sucker for a decent monster movie and this one has me salivating.

I had the first carol singer of the year this evening. And I mean singer, in the singular, rather than singers, in the plural. She mumbled one line of one carol and then looked at me expectantly. Sorry, no dice. I'm getting picky.

These days I want at least five people on the doorstep. At least one of the gentlemen should be wearing a top hat, the ladies should all have mufflers, and the guy at the back should be holding one of those lanterns on sticks. And it should be snowing. Otherwise I'm just not interested.

As we count down to the winter solstice and the mornings and evenings grow ever darker, I have to admit to feeling a strong urge to hibernate. One thing that keeps me going at this time of the year is chocolate; during my weekly visit to the supermarket last night I ended up buying four bars of Cadbury's chocolate (of varying flavours) because Sainsbury's were doing a special offer on the stuff. The improvement in how I felt after a few squares of the stuff last night was quite disturbing, but I am going to make sure I have a regular intake until I get out in the sunshine again, and weight gain be damned.

A craving for sweet foods and carbohydrates at this time of year is, of course, one of the symptoms of the "winter blues", more commonly called Seasonal Affective Disorder or SAD. I suspect I get a mild or sub-syndromal version, and I've done so for years without doing anything about it. This year however, I've felt so tired that I'm wondering whether getting a light box might help; they are supposed to be very effective and there are some quite nice desk lamps available which are supposed to do the trick. Even better would be this illuminated duvet and pillowcase. Wow.

A blunder by the Treasury could cost British taxpayers £3.5 million quid. Why? Because they classed Marks & Spencer chocolate-covered marshmallow teacakes as biscuits between 1973 and 1995. They should have been classed as cakes. It could only happen in Britain.

The writer Neil Gaiman points out that people are having *far* too much fun reviewing the humble Bic ballpoint pen on the Amazon.co.uk website. Reviews include poems, outrageous claims about provenance, complaints that they're region locked to specific sizes of paper, criticisms based on their unsuitability as improptu weapons for defending against vampires, warnings to consider the thickness of your clothing when clipping one in a pocket, and suggestions for alternative uses once the ink has run out. It has to be said that the Americans are way ahead of us with some even more loopy reviews for a gallon of milk. Thanks, Sam!

Neil Gaiman is, by the way, a true gentleman. As well as being a brilliant writer, he's also an extremely nice bloke. When one of his fans wanted to propose to his girlfriend in a creative way, he asked Neil if he'd help. The result is a couple of minutes of supreme sweetness that really makes you believe there's hope for the human race after all.

Less happy news from the writer Terry Pratchett, however. As was mentioned quite widely on the news yesterday, he has announced on Paul Kidby's site (under a typically Terry headline of An Embuggerance) that he has been diagnosed with a rare form of early onset Alzheimer's disease. A few years ago I was lucky enough to spend an afternoon in the pub with Terry and various members of alt.fan.pratchett, and I can honestly say that he is a very affable chap. He is as good at telling stories to a real life audience as he is writing them. He's courteous, intelligent and funny, and if life was at all fair he'll still be writing novels at the age of 140. Best wishes, Pterry.

I'm fascinated by the idea behind composer Phil Kline's Unsilent Night events. The basic concept requires you to sign up to attend the event with a music player - boombox, ghetto blaster, whatever. At the event you're given a CD, cassette or digital file with instructions on when to play it. Then, on a shouted command, everyone starts up their players and begins walking up and down the area of the city selected for the performance. Those cities are a fairly interesting mix: New York, Atlanta, Boulder, Detroit, Hamburg, Melbourne, Tallahassee, Philadelphia, San Diego, San Francisco, Santa Barbara, Seattle, Sydney, Vancouver, and Cleveland. Here in England, Middlesbrough has participated. As BB's Mark Frauenfelder said, last year's event in San Francisco had more than 1,000 participants. As a fan of ambient music, I'm intrigued. As Boing Boing mention it today as well, I guess I'm not the only one.

Ain't it Cool pointed me in the direction of a trailer for the new film Jumper, about a guy (Hayden Christensen, of Star Wars fame) who discovers he can teleport. All well and good for him, until he attracts the attention of Samuel L. Jackson, who is distinctly unimpressed by his abilities. The trailer looks like it might actually be a fairly good science fiction film. The concept of teleportation as a literary device doesn't start with Star Trek, by the way: it goes back years. I'm still waiting for someone to make a decent adaptation of Alfred Bester's The Stars My Destination, which was written in 1956. I still think it's one of the best SF novels I have ever read.

Visitors to the website of the Merriam-Webster dictionary have apparently decided that "w00t" should be word of the year this year. Oh dear. This has been widely reported, usually in a tone of voice which bemoans the fact that such a daft exclamation could even be regarded as a word (it contains two zeroes, after all). I find it far more irritating that facebook came second, primarily because it's another example of that bloody annoying habit that Americans have of turning nouns into verbs. Of course, the Americans came up with a name for the process of turning nouns into verbs which does exactly that: they call it verbing.

At least Bill Watterson's Calvin and Hobbes sends the right message: verbing weirds language.

Living in North America during the end of the last ice age could have been a dangerous affair. Researchers think that more than one nickel iron meteors exploded over the area, peppering those below with fragments, a bit like a shotgun blast. Pellets have been found embedded in the tusks of mammoths and in the skull of a bison from Siberia. Being clobbered by fragments of an incoming asteroid is going to hurt, no two ways about it.

It's interesting how our attitude to meteors has changed in the last three centuries. In the middle ages, people refused to believe that rocks could fall out of the sky and eyewitness reports to the contrary were rejected out of hand. Even at the end of the 18th century, the great French chemist Antoine Lavoisier analysed one meteor whose fall had been witnessed and concluded that it was a stone that had been struck by lightning because, as he put it, rocks simply did not fall from the sky.

Just over a hundred years ago Barringer Crater in Arizona was still believed to be volcanic. Even in the 1960s when I was a kid, it was believed that there had been no large-scale impacts on Earth in the last hundred million years or so. Things started to change with the discovery of the Chicxulub crater in the 1970s and people began to realise that impacts were rather more common than previously thought. Many other impact structures have been identified since then. In the immediate past we've been pretty lucky, although the Tunguska event in 1908 is now generally thought to have been an asteroid exploding between 5 and 10 km above the Earth's surface. Other large impacts may have taken place in South America in the 1930s and we came fairly close - just 57 kilometres - to having another North American impact on August 10th, 1972. You can even download a video of this near miss taken from Linda Baker's original 8mm film.

The latest discovery reported by the BBC suggests an impact 35,000 years ago. Scientists think there was another impact 13,000 years ago which wiped out the Clovis people in North America. In many cases, the large impacts coincided with mass extinctions or widespread volcanic activity. But according to a story in last week's New Scientist magazine, a cometary impact back in the early days of the Earth's history may well have been responsible for kick-starting plate tectonics. Plate tectonics are so important to the Earth's ecology that without that event, it's unlikely that we'd be here at all.

Those of you who have read Neal Stephenson's novel Snow Crash will be familiar with the rather far-fetched idea that the simple act of looking at stuff in a virtual world could infect you with a virus. Yes, that's right - looking. Not running a program, or typing a command, just happening to have your eyes open when you're pointing in a certain direction. Now it turns out that, in Second Life at least, it's possible to do exactly that. Time to turn off video streaming on my acount, I think. And call in Hiro Protagonist.

I was disappointed to hear that NASA have postponed the next shuttle launch until next year. But perhaps it's not surprising given what they apparently have to deal with in this video. I don't know, it's just one thing after another...

Today was a really nice day, but I hardly saw any of it. I've got a lot on at the moment at work, and keep on getting asked if I'd mind helping out on other projects. It's nice to be asked, but there just aren't enough hours in the day to get everything done. It was dark when I arrived at work this morning, and getting dark when I left. By the time I get home I'm knackered. December looks like it's going to be another fairly thin month for blog entries as a result.

Why is it that the weather can be unrelentingly miserable all weekend when it Sallie and I have the opportunity to go out for a walk, but it's only once I'm back at work that the clouds disappear, and the sun comes out? Mind you, the clear nights have meant that the temperature is finally settling down at the sort of value we should be getting at this time of year: it was well below freezing last night, dropping to -4.5° C.

I may be jinxing things, but so far the Billion Router I installed on Friday hasn't fallen over once. And I've been getting pretty good data rates all evening, too.

I finally got to speak to someone at Demon who actually knew what they were talking about - the reason I was having problems connecting was my router, which was on the point of expiring. So, one quick visit to eBuyer later I have a shiny new router which has been rock solid since I switched it on and syncs at over 3k during the day and even maintains 2k in the evenings. It'll take a few days for BT's BRAS profile for the line to notice this, but then I should be back to decent rates for throughput. I hope.

So far it has also provided a pretty decent wireless signal around the house, based on a few quick tests with an old PC and my iPod. As a result, I'm feeling much happier with my ISP.

With any luck, I can actually look at stuff online in the evenings, which will work wonders for my posting rate on the blog. Things have suffered in recent months partly because I've been busy, but mostly because when I did find time to surf, I couldn't get a connection. If things go as they are now (touches wood cautiously), that may not be a problem any more.

Ruth has been complaining that she's bored, so here are a few suggestions for things to do in these dark, winter evenings. First off, a selection from the rather amazing MAKE magazine (disclosure: one of Make's contributors is a Flickr buddy of mine) suggests that you might try your hand at:

• Painting toilet seats
• Making an outfit that really lights up the room
• Playing stuff on some MIDI tubular bells
• or perhaps constructing your very own DIY particle accelerator?

Then, of course, there's the old tried and tested stuff:

• Popping bubble wrap
• Throwing paper in the bin
• Getting a cat and putting stuff on it
• Surfing thousands of pictures at Ffffound!
• Gazing in amazement at Rock & Roll Confidential's stash of photos of stupid-looking bands
• Laughing yourself silly over at I can has cheezburger
• and playing with Microsoft's Photosynth.

Those should be good for whiling away a few hours, anyhow!

While I couldn't surf, I have been working my way through the new five-disc release of Sir Ridley Scott's genre-defining masterpiece, Blade Runner. I've put up a review of what I think of the latest version over on my film pages, but basically, it rocks. If you have a DVD player, this needs to be in your collection.

I'm not entirely sure why, but my connection to the Internet collapses every afternoon at about four o'clock and stays broken until about 11pm. This isn't helpful when I'm trying to update the website, so I need to get things sorted. Unfortunately with an ISP like Demon this is proving nigh-on impossible. They are completely useless when it comes to actually resolving a technical problem. At the moment, all I can say is that the blog might be a bit thin on the ground this month uuntil they sort things out for me.

Rebecca and the twins came down for the weekend. It was great to see them, as they haven't been down for a while. They asked me to provide some official Christmas pictures for them, so I got to do some portrait photography. I really enjoy doing this, but living on my own means that I don't get many chances to practise. Here's a black and white version of the one that we thought was the best:

I'm really pleased with it, as it's a lovely portrait of both Rob and Ruth. And as Ruth mentioned that she always checks my blog to see if they've got a mention, I hope this will do the job!