Wednesday 21 December 2011

More Earthlike exoplanets

A little update on the ongoing search for planets. NASA confirmed yesterday that the Kepler telescope has successfully located two planets of Earthlike size and mass. After the 'twin' planet of Kepler-22b getting all the fanfare, this latest discovery has slipped by with little fanfare, yet it's just as significant, since these are the first confirmed terrestrial planets of comparable size to our own.

The two planets have been located in star system Kepler-20, which has now been thoroughly investigated and has previously revealed three larger planets. With five planets, Kepler-20 is quite a busy system, although not the most populous known (HD 10180 and Kepler-11 both have a confirmed six planets, still behind our own system with its eight major planets). Kepler-20 is about 290 parsecs away (that's nearly 950 light years) in the constellation of Lyra, and is a reasonably close match to our own Sun.

So, these two new worlds, designated Kepler-20e and 20f, are the smallest ever found. Detecting planets this small isn't easy. There's a good article here on the discovery, which explains some of the long process that was required to confirm the discovery. There's also a nice little animation illustrating the planetary system.

The previously trumpeted planet Kepler-22b has a radius approximately 2.4 times that of Earth, while the previous record holder of smallest exoplanet was K-10b, the first confirmed terrestrial exoplanet with a radius of 1.4 Earths. It's clear to see that the Kepler project has been slowly getting closer to an Earth-sized planet. Now it has been rewarded with two. K-20f is the larger of the two, at 1.03 Earth radii, while its sibling K-20e is only at 0.87 of Earth's radius; roughly the size of Venus.


However, there's no use getting excited about alien life forms or comfortable planetary colony sites. All the planets found orbiting Kepler-20 do so much closer than Mercury does the Sun. K-20f is the outermost, and orbits in only twenty days. There is a slim chance it may retain an atmosphere of heavier chemicals - water vapour, perhaps - but K-20e, is in a six-day orbit, with an estimated surface temperature of 1040K, so there's no chance of it retaining any atmosphere.

It's a peculiar system altogether, really. Planet b is the innermost, followed by planets e, c, f and d - which means it's running big, little, big, little, big. The three larger planets are probably gaseous, and are somewhere in the super-Earth size band, smaller than Neptune - hot gas dwarfs. It's a far cry from our own system, with four terrestrial planets, two huge jovian gas giants and two smaller, colder gaseous planets, all much further from the Sun and from each other. It seems that the Solar System is by no means typical for the galaxy. It'll be very interesting to see what the next few planetary systems turn out to be like.

UPDATE: Only hours after I posted this, a further discovery was announced, detailing two planets found orbiting the star KOI 55 (aka KIC 05807616), a dying subdwarf. The two planets, KOI 55.01 and KOI 55.02 are even smaller than Kepler-20e, at 0.76 and 0.87 Earth radii respectively, and they have extraodinarily close orbits that last only a matter of hours. Betsy Green, one of the researchers on the project, has issued a statement saying that KOI 55 must have previously been a red giant star, having long since passed through this phase of its existence, and that the planets must have been drawn inside its mass during its giant period. Furthermore, to have survived this immersion in the star's outer layers, the planets must once have been gas giants, with their thick atmosphere's taking the brunt of the star's energy. The fluid layers would have been stripped away, leaving the dense metallic cores behind. Such planets, known as Chthonian planets, have been theorised before, but never definitively identified.

There's a detailed article on the findings here at the Daily Galaxy.

Sunday 18 December 2011

Doctor Who Christmas Special now available

Well, OK, not the Christmas Special. However, The Doctor Who Project has now made available its Christmas Special, Stromboli's Comet, by Jez Strickley and Jake Johnson.

You can download it for free here.

Friday 16 December 2011

Still searching for answers

Just read a very interesting article on the search for God in the Universe over at The Independent. There are plenty of articles out there that address the challenge of combining theology and science, but this is a particularly good example, addressing the various approaches and difficulties in just enough depth for an informative layman's article of reasonable length. There are also some reader comments that are worth checking out.

It's an intriguing ongoing debate. While I would consider myself an atheist - or, at least, a skeptical agnostic - I see no reason whatsoever why a scientist cannot also be religious. While the above article focusses on Christian scientists (not to be confused with Christian Scientists), there is no reason not to discuss the nature of objective, empirical science when applied to practicing Islam, Judaism, Buddhism, et al. I certainly find it impossible to correlate a rational view of the Universe with a literal interpretation of the Bible, or of any religious text. The twin creation stories of Genesis (for there are two, rather clumsily cobbled together - it's easy to see the join) are patently absurd, stories of an ancient people that have no place today beyond historical and mythological study. It's quite terrifying that there are still many, many schools in th United States that refuse to teach Darwinian evolution but which preach Biblical Creationism as fact.

And yet, there's nothing to stop a scientist from believing in a created Universe, or prevent a Christian, Muslim or Jew from accepting the tenets of empirical science. A literal interpretation of Old Testament stories is out of the question, but there is still room for a more developed, modern view of these religions, which many people worldwide ascribe to. I know less about pantheistic faiths, such as Hinduism, so cannot really comment on how compatible these would be with such an approach, although I'd be very interested to learn. Animistic faiths, still followed by many tribal groups throughout Asia, Africa, Oceania and the Americas, are in many ways highly compatible, worshipping, essentially, the laws of nature.

Personally, I find it difficult to believe in the Christian God, for the simple reason that the Universe, in all its complexity and splendour, is evidently not perfect, and I fail to see how an omnipotent, omniscient, omnipresent God could create a flawed creation, filled with suffering and basic errors. Too many children are boon with terrible, agonising genetic diseases for me to ever accept such a belief. However, that doesn't preclude the possibility of some form of Creator God.

Thursday 15 December 2011

Phantoms, Time Lords and Elder Things

On Monday night, my family and I went on an outing to Theatre Land, that garish and luvvie country nestled within Central London. My Dad treated us all to a night at Her Majesty's Theatre, to see the classic musical The Phantom of the Opera, now celebrating its 25th year. I love a musical, and it's been a good little while since I went to see one. Phantom was, I am pleased to say, absolutely fantastic. The early operatic moments were over the top, and I worried that the show might turn out to be rather naff. My concerns were totally unfounded; Phantom proved to be an astonishingly powerful play, with a roaring score backed by staggeringly effective sets and lightwork. It was the two-handed scenes that I enjoyed the most, particularly those that saw the Phantom (a rich performance by Earl Carpenter) in his attempts to woo Christine - played in this performace by Katie Hall, who isn't the regular for the role, something I don't understand, as she was perfect throughout. The entire cast were very good, although worth mentioning is Cheryl McAvoy as Madame Giry, and I've a particular soft spot for Anna Forbes as her daughter Meg, the ballerina.

Monday 12 December 2011

Two lost Doctor Who episodes - FOUND!

The BBC announced last night that two of the many missing episodes of Doctor Who have been recovered, and returned to the BBC archives in their entirety. Well, we call them 'lost' or 'missing,' but destroyed is a better term - the BBC committed wanton acts of vandalism against its own product throughout the Sixties and Seventies, wiping, and sometimes even incinerating, old video stock. The list of lost Doctor Who eps tallied a whopping 108, until two more were recovered recently. Staggeringly, according to the news story, both episodes were bought at a school fete in the Eighties, and have been kept pristine since then, with the owner unaware that they were missing from the archives. These aren't the original transmission tapes, which have all invariably been destroyed. However, film transfers for overseas sales resurface from time to time, very often having been sold on by foreign television stations and now residing in private collections.

Doctor Who isn't the only series to have suffered such a fate - Dad's Army, Hancock's Half Hour, Softly Softly, Not in Front of the Children, Adam Adamant Lives! - dozens of series are missing episodes. There's a list in this wiki entry, and we can see that cop shows were hit particularly badly - Dixon of Dock Green is missing 381 episodes, and Z-Cars a whopping 466! Although this does show just how prolific the creators of these series were, to have made so many episodes in the first case. Monty Python's Flying Circus almost lost its entire first series, according to the tales, but the engineer charged with the task of wiping it decided to pinch it, and took it home instead. Good forward thinking, that man. Emergency Ward 9 also turned up in this latest haul, along with a Pete and Dud sketch - slowly, the BBC is getting its goods back.

So, Doctor Who is missing over a hundred episodes from the Sixties, featuring the original Doctor, William Hartnell, and his successor, Patrick Troughton. Thankfully, one episode for each has just been discovered. For Hartnell fans, we have Air Lock, the third episode of Galaxy Four - a major find, as this was one of the truly lost stories, with only tiny fragments of film remaining as a visual record. Troughton lovers can look forward to seeing Episode Two of The Underwater Menace, which joins the third episode in the archives, leaving episodes one, four, five and six still unaccounted for. Menace is widely considered one of the worst stories of the Sixties, but still, it's a laugh, and it's great to be able to actually see the lunacy again. Clips from both shows can be seen at the Doctor Who News Page.

So, this leaves 106 episodes still missing from the archives. It's unlikely there are many more out there - not all can be as fortunate as these, and been saved from a second act of destruction and acquired by collectors. Still, they do turn up from time to time - the last time this happened was back in 2004, when the Dalek episode Day of Armageddon surfaced. Until the next lucky find, we can make do with the off-air soundtracks - fortuitously recorded by industrious fans during the original broadcasts.

Best have a quick check in the loft though, just in case Grandad hid the complete Marco Polo up there. You never know.

Wednesday 7 December 2011

A new Earth?

The latest scientific story to grab the headlines is the discovery of planet Kepler-22b, an apparent 'twin' of the Earth. This is certainly a fascinating and important discovery, but the matter has been overstated.

Kepler-22b, located 600 light years away on the edge of Cygnus, is the most Earth-like planet so far discovered beyond our solar system. It is the first planet of a comparable size to our own to be confirmed to exist within its system's habitable zone. Smaller planets, closer to that of the Earth, have been detected, but so far all orbiting their primaries at close proximity that would likely make them too hot for life. Kepler-22 is a Class-G star, much like our own, but a little smaller and dimmer; the planet lies 15% closer to its star than we do to our Sun, putting it in a similar position heat- and radiation-wise.
So, the position is a good one, giving a potentially temperate environment for the planet. Yet the 'twin' aspect of Kepler-22b to Earth has been overstated by the stories. The planet has a radius about 2.5 times greater than the Earth's. That's a pretty good approximation of the Earth, in the scheme of things, but not quite what I'd call a twin. As a contrast, look at Venus. Venus is almost an exact match for Earth, size-wise, and is very similar in terms of structure and composition. It's also within the solar habitability zone, just about, so you would expect an environment very similar to that of the Earth. Yet Venus is a broiling hellhole, and any human being who set foot there would be immediately choked, crushed and boiled to death. Venus is a much better match for the Earth than Kepler-22b, but it's hardly a promising colony site.

Saturday 3 December 2011

Things to look forward to in the Whoniverse

I'm supposed to be writing some fan-fiction, but I feel like I've swallowed a cactus and my brain seems to have turned to porridge. So I'm going to attempt to get myself in the Doctor Who mind set properly. I've rewatched The Doctor's Wife and listened to part two of Serpent Crest, and am now amusing myself by looking ahead to what's to come in the world of the Doctor.

The Radio Times has a nice preview ahead for the Christmas special, The Doctor, the Widow and the Wardrobe. I'm starting to really look forward to this one. I enjoy the RT articles on Doctor Who - they usually get the balance right, neither fawning over the show or mercilessly tearing it apart, and, while I might not necessarily agree with a review, I always feel the reviewer has been fair in their appraisal. RT previews often put a little hint in for diehards, letting them know of a reference to watch out for. It's a fun little fan game. Apparently there's a nod to a 1984 story in this one, so I'm hoping the Malus is hiding somewhere in the woods. Plus, there's a host of new images, including this marvellous one of Bill Bailey in a spacesuit:

I adore Bill Bailey, and I'm pleased to see that he hasn't changed his classic bemused expression for his Who appearance. Whenever I see him on TV, he always looks as if he was expecting to be somewhere else, as if he's just walked into the wrong room.