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(I hope you realise that most of your post consists of the well known strawman fallacy)

Oh good, so if I was setting up strawmen, then you aren't claiming that Mann et al 2008 used tree ring data improperly? Because that's the only position I attributed to you, as far as I can see. It would explain why you never supported that position; you never held it in the first place, you just insinuated that it was true.

Baillie, and many other dendrologists, are very wary about using tree rings as temperature proxies. I.e, your claim that Baillie's comment is about Keenan specifically is not correct, it's about oaks - no matter who uses them. (Climate signal in tree-ring chronologies in a temperate climate: A multi-species approach. Suarez, Butler, Baillie, 2009)

Did you even read the paper you're citing here? Did you even read the abstract? For those of you with access to it, here's a link to a pdf of the actual paper (it might be public access, I don't know).

Here's a quote from the abstract:

We nd that the moisture-related parameters, rainfall and the Palmer Drought Severity Index (PDSI), and to a lesser
extent, maximum and mean temperatures, can be reconstructed.

Then look on page ten. There's a heading. It's "Reconstructions". In that part of the paper, Suarez et al (and in this case, et al includes Baillie) proceed to reconstruct temperature data using tree ring data. So apparently, Baillie's statement is about oaks, no matter who uses them - including the Baillie himself. Indeed, the point of this paper is that by using multiple tree species you can extract okay data from just the dendrochronological record. Keep in mind that Mann et al weren't doing that - they were using the dendro record plus other proxies. This paper is about how far you can get with just dendro and some calibration.

As a side note, I would be wary of citing the Wegman report; the social networking segment, at least, is full of outright plagiarism which is kind of concerning.

Anyway, now that I look at Mann et al 2008(warning, pdf and also you might not have access to it), it doesn't matter if the bristlecone data isn't that great. Here's a quote from the paper:

For both methods, we perform reconstructions both with and without dendroclimatic proxies to address any potential sensitivity of our conclusions to issues that have been raised with regard to the reliability of tree-ring data on multicentury timescales(4,11,16,19,33,34).

And guess what? It doesn't really make much of a difference. Here's (pdf again) a graph of the various reconstructions both with and without tree ring data; the no tree lines spike a bit more, but are generally consistent.

Funny how the website you linked to never even mentions this fact. Weird, huh? It's almost like they (and you) didn't read the actual paper.

Oh yeah and if you're wondering how they know that Mann et al has exactly 119 oak tree records in their reconstruction, it's because the stuff is available online. There's a link in the paper.

...a "planet" is defined as a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighbourhood around its orbit.

Back when I used to call myself an astronomer I coded up this map which shows the releative postitions of all asteroids in the vicinity of the earth. If you've ever played the classic video game 'Elite' then you won't have any trouble understanding the map.

I bought a USB Radioshark, set it up under Linux, and used Icecast with Liveice to setup realtime streaming.

I then setup a cgi to change stations. Works like a charm.

And I recently re-did some density visualizations, a lot. more abstract, but cool in a trippy visuals kinda way.

And finally - the most relevant - is an old movie I made to visualize a comet diverting mission, it's about 10 minutes and if shows a spacecraft flying through space with a nuke intended to give a nidge to an incoming comet. It's not great resolution, but I can't find the high definition versions that were used in a couple of TV shows. There are some ultra high definition stills in a book by Duncan Steel.

And I recently re-did some density visualizations, a lot. more abstract, but cool in a trippy visuals kinda way.

And finally - the most relevant - is an old movie I made to visualize a comet diverting mission, it's about 10 minutes and if shows a spacecraft flying through space with a nuke intended to give a nidge to an incoming comet. It's not great resolution, but I can't find the high definition versions that were used in a couple of TV shows. There are some ultra high definition stills in a book by Duncan Steel.

Math boxes allow for greater flexibility and adaptability to varied mathematical abilities. (This text is the only one that gives the instructor a choice of teaching planetary science either at a descriptive level or at a moderately advanced level involving algebra and elementary calculus.)

b) According to the IAU's Committee for Small Body Nomenclature, three objects are both minor planets and comets: Chiron, Wilson-Harrington, and Elst-Pizzaro. Your comment that "comets and asteroids have very different histories and compositions" is irrelevent, as the histories and compositions of individual objects are often not known (even spectroscopy can only tell you about the surface, not what's beneath). Thus an object that has never been known to sport a coma is typically designated as a minor planet (i.e. asteroid) regardless of composition. The clear-cut distinction between asteroids and comets disappears in the face of observational constraints.

c) Armagh Observatory, on Centaurs: "These bodies, many of which have diameters greater than 100 km, are called "Centaurs" because of their "half-comet, half-asteroid" status." There are many links on that page to other pages discussing the controversy surrounding the naming of objects. Centaurs are usually referred to in the literature as asteroids, not comets. Notice that the Minor Planet Center (which was given responsibility by the IAU of designating minor bodies in the Solar System) lists Centaurs on the minor planet orbits page, not the comet orbits page.

The nomenclature problem isn't limited to Centaurs, as discussed in this excellent but dated Spacedaily article, which says (referring to a April 20, 2000, "Nature" article by Dr. Don Yeomans):

Yeomans in Nature points out that recent computer simulations show that as much as three percent of Kuiper Belt objects are likely to be rocky asteroids that formed in the outer fringes of the Asteroid Belt -- but then, at some point over the eons, flew close enough to Jupiter to be catapulted by its gravity into the outer Solar System.... [M]eteorites have been found still containing significant traces of water trapped inside them -- which means that "Far from being the dry rocky bodies they were once thought to be, it would seem that some asteroids, along with with comets, might be significant sourcees [sic] of water."

Google is my friend. Is it yours?

I wasn't talking about Sedna. I was responding to a general statement you made about asteroids, not any particular asteroid.

Check the 'most complete map of the solar system' at http://szyzyg.arm.ac.uk/~spm/

But it just makes all those long term asteroid orbit simulations a little harder now, since not only do you have to know the position and velocity accurately, you now have to know it's spin and it's thermal properties. It's a great example of how orbital mechanics can be considered chaotic on reasonable timescales.

Oh since I'm here - Oblibatory link to my map of the solar system showing all the near earth asteroids.....

http://szyzyg.arm.ac.uk/~spm/

I have real issues with some of the reviews these guys post. In particular they don't seem to pay attention to any of the background justification in the movie.

For example - in the Matrix they spend a lot of effort pointing out that the jumps and kung-fu moves the protagonists pull off are impossible according to the laws of physics. COmpletely ignoring half the story which explains that people can do these impossible things because it's just a computer simulation they're hacking. They even seem to have major problems handling the concept of bullet time - "Trinity (one of the hackers) jumps five feet off the ground and pauses in mid air before kicking a policeman"..... tsk tsk

Sure the whole 'batteries' argument is bad movie physics, but most of the rest of their review is them applying textbook physics in places where it doesn't belong.

Or how abotu star wars where they point out that the force fields are transparent to light but they seem to stop the 'laser beams' - ignoring the fact that the weapons used in star wars clearly are something different from laser beams because they don't travel at the speed of light.

Basically these guys don't cover the genuinely insulting movie physics where writers setup some futuristic technology e.g. time travel - then

Of course, given that I worked as an astronomer writing papers on asteroids and comet impacts I've made more than a few analysis of Deep Impact and Armageddon. (both were bad in different ways, but I liked Armageddon for it's stupidity). Their reviews are rather shallow and I've pointed out a few errors to them, never had a response though.

A larger version.

Or this one, or this one, or this one, or this one, or my favourite: this one.

Artists seem to like to portray asteroids as being sveral hundred kilometres in size.

... about the Leonid shower is the Armagh observatory site at http://www.arm.ac.uk/leonid, with lots of explanations, pictures, tips and so forth. Everything you need to know.

The Armagh Observatory has perhaps the best page about the Leonids that I've found online. It includes information about predictions, rates, storm likelihood, America vs Asia, danger to spacecraft, viewing and photography tips. Try it.

David Asher at Armagh Observatory has an explanation and plots that answer my question. He and Robert McNaught in Australia have calculated the orbits of debris streams ejected during many past apparitions of the comet. The outer planets perturb each stream differently. In 2001 Australia and Asia should get 15000 meteors per hour from the combined 1866 and 1699 streams. The Americas should get 2500 per hour from the 1767 stream. The 1966 storm was a direct hit on the relatively fresh 1899 stream. They think the numerous bright Leonids seen in 1998 may have been ejected in 1333.

Check out this link to the Armagh observatory.

The method they use successfully predicted the peak to within about 5 minutes last year.

The estimates for the Americas this year are 2500 per hour and something like 30,000 per hour at peak in 2002!

My Map of all NEOs

BBC coverage of these events

My 'Musical Interpretation' of the report ;-)

Nowadays though, I'd suggest you use Icecast + Liveice - there are a few websites already doing this. But - as the author of Liveice I must admit that my documentation sucks, so if you have any problems then I'm always available for answers. Somtimes I even do hacks to order.

Liveice supports Soundcard Input, as well as multichannel mixing of mp3/wav/whatever. It can run as daemon and also supports almost every encoder available for linux. It also permits you to stream the same input at multiple bitrates - something which is probably essential if you're to cater for everyone. I've also got a plugin for xmms, but since there's no line in input plugin it's not so much use for live stuff just yet.

One major bit of advice I give to everyone - Get the latest version from my web page.

I'm terrible with CVS which is why most of my changes/improvements aren't in the tarballs/CVS on iceacst.org - one day when I have time to clean it up for a proper release.

(And while you're at it - why not listen to my latest selection of Scottish Music)

I've gone and higlighted it on my NEO map so you can all see where it is right now. (look near Venus). I presume this is the same object they're talking about.

It's not actually a moon of the earth, at least I wouldn't consider it a moon. Trojan objects aren't bound to their objects in the same way that moons are. Certainly the Earth's influence acts to stabilise the orbit, but if that's teh only criteria for an object being a moon then perhaps we should consider Pluto a Moon of Neptune since pluto is help in the 3:2 resonance with Neptune.

Oddly enough - the 1:1 resonance of trojan objects with respect to the Earth make it almost dynamically impossible for the object to ever become a true satellite of the Earth.

First, on the astronomy side, this will be the last good Leonid meteor shower. Ever.

Not true. There are much better showers predicted for 2001 and 2002 - have a look at this report - specifically the predicted "ZHR" (Zenital Hourly Rate - the number of meteors seen per hour under ideal conditions) in table 3.

Anyone know whether the show will be visible from Europe, specifically the UK?

Probably not, as it will probably be cloudy!

But, clouds notwithstanding, it should, indeed, be visible from the British Isles. You should go and have look, prefereably between 1am and 3am.

See this Armagh Observatory site for more information.

Actually, with liveice and icecast, it can work quite well. You can configure it to use different encoders like FhG and Xing to encode the audio live from the soundcard. I'm the student engineer at my station here in Miami, WVUM, and we're in the process of putting together a box for this purpose. Some guy from the school of communications tried to sell the advisory board on RealAudio, but for any decent amount of users, the licensing cost goes into the tens of thousands of dollars, even with an "educational discount." We're going to try to use Live 365 for starters, until we get more bandwidth from the university. If anyone has any advice or experience on that or any related issues, please feel free to share.

I recorded my own version of adminspotting in one of my radio shows.... you can download the mp3 from http://szyzyg.arm.ac.uk/~ spm/live_mpegs/adminspotting.mp3.

It's a bit old now ..... but still amusing

explorezone.com has a news article on this which includes and interview with the astronomers.

My map of Near Earth Objects has 1999 AN10 marked on it, and will be updated daily. It's Currently the red object near mercury.

And Benny Peiser's Cambridge Conference network mailing list broke the news of this to it's readers - readers like Arthur C Clarke, Bill Napier, Mark Bailey and other big names in the field.