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You're right. Obviously the astronomers involved made all this stuff up. They haven't got a preprint of a their report to Astrophysics Journal posted on the web, or anything like that. And popular science journalists would never try to get cute with the pictures they choose to go with their articles. I mean that just doesn't happen.

Though the BBC is a reputable source and usually gets their facts straight, they're not to be mistaken for a peer-reviewed journal. A two-hundred-word article isn't going to have a full complement of figures and supporting data--and it shouldn't be expected to.

Mods--the parent post is funny at best; not insightful. I have this amusing mental image of a bunch of drunk astronomers drawing random circles on star charts and saying, "Okay, this week we'll tell them there's dark matter here. Suckers."

More detailed information can be found in the paper, which has been accepted for publication in a letter to the Astrophysical Journal.

Find it here.

All measurements of stellar velocities are not the stars true velocity - they are "radial" velocities. This is the geometric projection of the stars 3 dimensional velocity along the line of sight. Now, when you do this, everything is moving and many corrections must be made.

First, we correct for the rotation of the earth, and the movement of the earth around earth-moon barycentre. Then we correct for the earths movement around the sun. This is what is usually reported, and it is called the Heliocentric (i.e. centred on the sun) radial velocity.

Now the sun moves a little bit (about 20km/s) with respect to stars in our local neighbourhood, so we correct to this so-called "local standard of rest" or LSR.

From the LSR velocity, we can take out the movement of the sun aroudn the galactic centre, and put it in a galactocentric standard or rest, or GSR. This is done via the relation
v_GSR = v_LSR + 220*sin(l)*cos(b), since the sun has a circular velocity around the galactic centre of about 220km/s. l and b here are the galactic latitude and longitude, with (l=0,b=0) the galactic centre and l increasing counter-clockwise.

So, what we really care about, is the GSR velocity, from which we can tell whether the star is bound or not (i.e. is v_GSR > escape velocity).

There is a link to the actual article here (which has been submitted).

BUT! Don't forget, we measure only 1 component of the velocity (towards/away from us) - we really need all 3 (side-to-side as well) which are called "proper motions". So it could in fact, have higher a higher velocity.

HTH

FWIW: The highest energy particle ever detected carried an astonishing 50 Joules. That's equivalent to a 1kg object hitting you at 22mph. Ouchies.

Or, as Samuel Johnston put it:

Knowledge is of two kinds. We know a subject ourselves, or we know where we can find information upon it.
--Boswell's Life of Johnson, Chapter 33

wouldn't it be nicer to name your inc variables xxx ? ... it's fun!

Which reminds me of my favourite sites to visit when my internet access is through monitored firewalls (corporate or university systems)

http://xxx.lanl.gov/
http://xxx.arxiv.cornell.edu/
http://xxx.adelaide.edu.au/
http://xxx.uni-augsburg.de/

Yep, folks - Governments and Universities worldwide, hosting xxx sites. And for what it's worth, xxx.lanl.gov was the original!

• The Shape of Things to Come (1936) based on the H.G. Wells novel of the same name.
  
• The Man in the White Suit (1951) speculative fiction with Sir Alec "Obi Wan" Guinness.
  
• The Fantastic Planet (1973) Psychadelic animated european sci-fi.
  
• Wizards (1977) Ralph Bakshi, 'nuff said.
  
• The Quiet Earth (1985) freaky end-of-the world stuff.
  
• Bill and Teds Excellent Adventure (1989) <simpsons voice="comic book guy">Best! Time-Travel! Movie! Ever! </simpsons>
  
• Until the End of the World (1991) with William Hurt and Sam Neill, oddly catches the essence of Gibsonian cyberpunk without the punk.
  
• Just about anything by Hayao Miyazaki but especially Laputa: Castle in the Sky (1986) or Nausicaä (of the Valley of the Winds) (1984) (but not the god-awful Warriors of the Wind from 1986).

Do not download or read these books online if you are in a country where copyright protections can extend more than 50 years past an author's death.

Among other things you can download Orwell's complete works and The Great Gatsby.

The University of Adeliade has a slicker version of the same texts.

Different Hobbes to the one in you sig, methinks: http://etext.library.adelaide.edu.au/h/h68l/chapte r30.html

Allegory of the Cave

I followed the link you provided and further skimmed through Amundson's account of the expedition... and your analogy fails.

Amudson himself notes in "The South Pole" that the supposedly "cold, barren land of ice and wind" was actually "teeming with animal life". He relied on accounts of other explorers before him as to what to expect along the way. They ate reasonably well on penguin and seal, and of course were surrounded by lots of (frozen) fresh water.

I fail to see how you can compare this type of environment with space travel.

The Barr Smith library of the University of Adelaide http://www.library.adelaide.edu.au/ in South Australia uses Mozilla firefox on SUN workstation for access to library search and reservation system.

Just check out the Athens soccer stadium!

Ahh, but what happens when the Earth suddenly stops rotating?

Glass flowing is a myth.

Old glass manufacturing technics were VERY imprecise. You might end up with a pane that had a thicker edge, in which case you would naturally put it on the bottom for balance.

Or you might end up with fairly uniform edges but have an irregular surface that looked like it was "flowing" but was static. I have picture windows in my house that are about 70 years old that have this "flow" pattern and have had people remark that the liquid must be pooling ... it's simply irregular hand-made glass.

Even if glass -does- flow (see the "a" link at the beginning), math shows it would take millions of years to complete the process, meaning no glass made by man would yet show visible signs of deterioration.

And you're right, "glassy" in this case is about the physical structure of the metal, not the light transmitting/absorbing aspects though those are probably mildly affected (I imagine a glassy steel will hold a shiny polish better than a crystal steel).

Maybe they can set up web site polls instead of this at rest stops.

Here at Adelaide Uni, Australia, where I'm currently in 2nd year Computer Systems Engineering, everyone who does CS or any of the Electrical Engineering degrees do a semester of DLX assembly... and I'm pretty sure there's more to come in later years.

According to this:
1807 - British Abolition Act bans any British participation in slave trade
1808 - US abolishes slave trade
1818 - France outlaws slave trade
1833 - Britain emancipates slaves
1848 - France emancipates slaves in colonies
1865 - 13th Amendment to US constitution abolishes slavery

Since you couldn't be bothered to include it yourself:

XIII

That a well regulated militia, composed of the body of the people, trained to arms, is the proper, natural, and safe defense of a free state; that standing armies, in time of peace, should be avoided as dangerous to liberty; and that, in all cases, the military should be under strict subordination to, and be governed by, the civil power.

... that plain old ASCII is one constant that hasn't needed changing.

I think you're a little unclear as to what ASCII is. As the "A" in "ASCII" indicates, it's oriented towards American applications. And it consists of a mere 127 characters, which includes 32 control characters that you don't use in text.

In point of fact, Project Gutenberg has long outgrown the 96 graphic characters in ASCII, though I think they themselves are ignorant of the fact. The seem to have experimented with characters until they found a set that displays the same on "normal" Windows, Macs and Unix/Linux. The result is something they call "extended ASCII" but that's actually subset of both ISO's Latin1 character set and Microsoft's Latin1 code page.

When is this an issue? Well, I'm a DP volunteer, and I'm concentrating on the Britannica 11th edition. Lots of geographic entries, all of which contain degree symbols. This symbol is not in ASCII! If you follow the DP instructions, you end up entering byte 186 (decimal). If you're using the ISO or Microsoft Latin1 set (and if your computer is localized for the U.S., Canada, or Western Europe, you probably are) then 186 does in fact display as a degree symbol. But if your system is localized for Eastern Europe, you're probably using Latin2, and this byte stands for an S with a cedilla accent!

In short, "ASCII" is actually less universal than well-formed HTML. In which you represent the degree symbol with a character entity (&deg;) that's the same everywhere.

Indeed, you can open up the original Declaration of Independence document with your standard web browser, and you can still read it just fine.

Hardly a representative example. The Declaration of Independence was hand-written, and thus doesn't include a lot of fancy fonts or formatting. A better example is a contemporary novel, such as 1984.

As it happens I just finished re-reading this one. I read a Plucker file that somebody had transformed from an HTML version, which in turn came from the Project Gutenberg "ASCII" version. Readable enough. But all the typographic nicities -- italics, boldface, etc. -- were reduced to ALL CAPS in the text version, and that was retained in the HTML version. Pretty distracting -- made me feel like somebody was shouting at me. Double Plus Ungood! Thoughtcrime!

...once the data is put into ASCII text format, projects like this [XML] can and are being done.

You make it sound easy. A lot of information is lost when your primary version is "ASCII". It all has to be put back by hand. There's no avoiding this for the large body of existing Gutenberg texts. And of course as recently as 5 years ago, there wasn't a real choice anyway. Even HTML had issues, and serious XML tools didn't exist.

But now XML technology is pretty mature. It makes sense to store new Gutenberg texts in XML. If people still want "ASCII" copies, the XML is easily transformed into that. Though I a lot more people will want the HTML version -- a format which is actually accessible to more people than "ASCII".

There are two reasons this won't happen soon.

The first is that somebody will have to design and implement the necessary XML apps for inputing and proofreading the texts. (Which would alsio elminate a lot of the errors proofreaders make, like entering [Greek: Tau] when they mean [Greek: T].) A huge project. As it stands, the people who maintain the DP web site have their work cut out just to keep the existing software working. That's a vali

I'm an environmentalist also, and I second your critique of these puerile pretenders. I'd add this to your list of alternatives: (11) Living in pre-industrial society.

The organization behind this windmill effort is Cape Wind. Their site includes a map which shows that the proposed windfarm lies at least three miles from any landmass. I can't think of a less obtrusive way to create this much energy. Most people in the world would give a kidney to live in these environs! What a bunch of self-absorbed clueless whiners!

Adversarial nincompoops will surface to decry any large public initiative, no matter how benificial or banal. The important thing is to make sure we don't structure our legislative processes such that a handful of nitwits can derail or impede public works with such immense support. Of course we must alway protect the minority opinion. But we cannot allow yippy little chihauhaus to rule the pack. Not when our future is at stake.

Ooh...one more good link.

• Mystery Spot Road, off Branciforte Dr. Santa Cruz, CA, USA. A spot 50m in diameter in the redwoods of the Santa Cruz Mountains
• Mystery Spot, Putney Road, Benzie County, Michigan, USA.
• Gravity Hill, Northwest Baltimore County, USA. along a public road that ran through the Soldier's Delight environmental area.
• Gravity Hill, Mooresville, Southwest Indianapolis, USA. Located off SR 42 on the South side of Mooresville.
• Gravity Road, Ewing Road exit ramp off Route 208, Franklin Lakes, USA.
• Mystery Hill, Blowing Rock, hwy 321, Carolina, USA.
• Confusion Hill, Idelwild Park, Ligonier, Pennsylvania, USA.
• Gravity Hill, off of State Route 96 just south of New Paris, Bedford County, Pennsylvania, USA.
• Gravity Hill (near White's Hill) , just South of Rennick Road, on County Truck U, South of Shullsburg, in LaFayette County, Wisconsin, USA
• Oregon Vortex, near Gold-Hill, Grants Pass, Oregon, USA.
• Spook Hill, North Wales Drive, North Avenue, Lake Wales, Florida, USA.
• Spook Hill, Gapland Road just outside Burkittsville, Gapland (Frederick County), Maryland, USA.
• Magnetic Hill, Near Neepawa in Manitoba, Canada.
• Magnetic Mountain, just off the Trans Canada highway, Moncton, New Brunswick, Canada.
• Gravity Hill, on McKee Rd. just before Ledgeview Golf Course in Abbotsford, British Columbia, Canada.
• Electric Brae, on the A719, Near Croy Bay, South of Ayr, Ayeshire, Scotland.
• Anti-Gravity Hill, Straws Lane Road, Wood-End, Near hanging rock, Victoria, Australia
• Morgan Lewis Hill, St Andrew, Barbados.
• Hill South of Rome, in Colli Albani, near Frascati, Italy.
• Malveira da Serra, on N247 coast road West of Lisbon, Portugal
• Mount Penteli, on a road to Mount Penteli, Athens, Greece
• Mount Halla, on the 1.100 highway a few miles south of the airport, near Mount Halla, on the island of Cheju Do, South Korea

> more like from the compleat-misspellings dept. ;)

Actually, "compleat" for "complete" in the titles of guidebooks is an ancient and revered practice, going back to this book.

I guess you learn something every day, huh?

As a libertarian I've become well-acquainted with the "hijacking" of terminology -- to the point of which it becomes exceedingly difficult to discuss some subjects because the people discussing it may not be talking about the same thing...

One example of this is the term "liberal". Once upon a time this had a very different meaning, and "classical liberalism", while on some issues resembles modern liberalism, is very different on many others. I doubt someone like Tom Paine would agree with much of what today's Democratic party supports.

Another example is "anarchy". To the Republicans, it's equated with chaos and a lack of any form of control, though in actuality it's meant to describe a social system that relies on self-control. To the socialists, it could only mean "classical anarchy", or "anarchosocialism", a sort of communist utopia. Libertarians often support "anarchocapitalism", where people can own the means to production.

The term "libertarianism" has been similarly obscured in meaning. Socialists have attempted to claim it for their own in the past. Many people, including the leadership of the Libertarian party, consider it equivalent to minarchism, while other influential people seek to equate the term to a restriction against the initiation of force. Meanwhile, other organizations also wish to subsume the term.

Nah, you can always argue that away by reducing the plasma density and increasing the external field.

It doesn't work (I think- I haven't built one) because the protons bounce down one propellor vane and then back up another.

I came up with this device when I was doing a homework assignment in college. Feynman's machine is much better.

So .73 seconds has nothing to do with how long it took the particle to pass through the earth. As the diagram indicates, that time is 27 seconds.

Another detail: although the researchers located a "pair" of events (that is to say, "two" events) they are NOT "paired", that is to say, associated with each other.

They found one event in October of 1993 and another event in November of 1993. They make no claim that the two events were caused by the same particle.

--Brent

Math & Music

tconnors(UID #91126) posted a link to the original paper, the last time this was posted on /.

Not to karma whore or anything :), but this is a fascinating paper. They talk about how Strange Quark Nuggets contain strange, up and down quarks, which makes them stable enough to exist without condensing into protons and neutrons. It also talks about how SQNs are dark matter candidates - so these paired seismic events may be proof of this form of dark matter.

This seems like an amazing amount of work - they went through nearly 10 million seismic event records, from 1981 to 1993.

It goes like this: friend on IRC says "I'm gonna kill your box tonight, log on to watch the carnage". Thinking he's about to do some security evil, I ifconfig down when going home. Get annoyed phone call that night saying "but I was only going to slashdot you, have you no trust?". Next day, query /. eds and get mail from michael@slashdot saying "your page is scheduled to go live in 3.5 hours". Loads of warning, so I had the "Hello Slashdot" up 2 hours before it actually hit slashdot.

Preparing the low-res version took literally 2 minutes, I already have software to make jpeg thumbnails from directories of pictures.

Actually, the traffic isn't so bad now, so if you want to see the hi-res version, it is available. Only go here if you're interested, otherwise use the original link.

Secondly, I do contribute to open source projects.

Perhaps this proves you right? He says that he's working on a "PhD at Adelaide University, Australia" and the submitted article is from that school. There plenty of equally fascinating *laugh* material in the root web for the truly bored.

Briefly, a ton sized SQN would have dimensions of about 20 microns, the size of a blood cell. As it passed through the earth it would break inter and intra-molecular bonds, like a stone ropped in water, producing a seismic signal.

http://xxx.adelaide.edu.au/ftp/astro-ph/papers/020 5/0205089.pdf .

They did not just "...went looking through a huge pile of earthquake data just to find two seismic events that happened soon after the other...". (look at the nice figures if you're to lazy to read it)

And by the way, it's only a theory which got blown up by media, don't blame the scientists for anything, I'm sure they're just doing their job.

Thanks for the list...
I'm sure Tristrom Cooke's email account is now going to be /. with updates.

Now I know what I'm doing this weekend (i.e. Looking over my library and rating my books)

The winds, even though the atmospheric pressure is low, are still capable of moving sand. Over a couple of million years, this may well change a planet's geology. Go take a look a the grand canyon to witness the effect of time.

When they're talking about the intense radiation from the sun, they're not worried about the survival of the drill or lander. They're talking about the the radiation destroying evidence of life on the surface, and that's why they need to drill. Since the atmosphere is so thin, you can expect a heavy dose of radiation at the surface. There are worse things than UV, such as high energy cosmic rays, which are mostly blocked by earth's atmosphere, but can penetrate a lot further on Mars.

I think this says it nicely :)

Since functions are degenerate relations, and people need relations (remember the relational databases need stored procedures etc. guys) my favorite foundational prototype for "light-weight programming languages" is Libra -- a programming langauge based on binary relations. It's not what I would have done as a prototype, but hey, the guy DID IT and here I am talkin' about it! :-)

Since functions are degenerate relations, and people need relations (remember the relational databases need stored procedures etc. guys) my favorite foundational prototype for "light-weight programming languages" is Libra -- a programming langauge based on binary relations. It's not what I would have done as a prototype, but hey, the guy DID IT and here I am talkin' about it! :-)

Natural language interfaces are, well, "natural" and should be pursued but there is a lot of room for a synthesis that trancends graphical and textual representations. It's just that most of the thinking in this area has been very ad hoc and insufficiently disciplined to take very seriously.

The nanobacteria subject is fascinating but it's another example of a story that is sometimes associated with extra-terrestrial life - probably to gain publicity.

Hmmmm... interesting take, but I don't follow the logic. Robert Folk ruined his reputation with the original "nannobacteria" proposals, and has only recently been supported somewhat by McKay et al. with the "martian fossils", Kajander and his collegues with nanobacteria as a cause for kidney stones, Miller-Hjelle and her collegues with nanobacteria as a cause for polycystic kidney disease, Uwi ns and her findings on nanobes growing on Triassic and Jurassic sandstones collected from petroleum exploration boreholes offshore Western Australia. The American Society for Microbiology has paid serious attention to the controversy, as might be expected. All in all, it's only been recently that "nanobacteria" findings have provided any good publicity at all; mostly, it's been the ruin of the discoverer (in fact, Folk has been described as "coming out of the closet" with his first papers, some 20 years ago -- strong prejudice exists!).

But now things are changing: there are more findings, and more support for the concept. This might even be a scientific paradigm change... and this was my earlier point, that "common sense" arguments are inherently flawed, because the universe is stranger than we imagine.

When was the tectonic plate theory accepted? They must have been interesting times. Certainly my father thinks it's a lot of nonsense...

Alfre d Wegener proposed the theory in 1912, but it didn't receive much support (in the U.S., at least) until post-WWII. My college geology text has a chapter written in '65, which concludes "Although the subject is now a respectable one in scientific circles of the Northern Hemisphere, the question is still far from settled." (Physical Geology, Leet and Judson, 3rd Edition; Prentice-Hall, NJ, 1965)

Wilson, a Canadian geologist, brought everything together around '65 with his model of seafloor spreading, which happened to explain the Pacific seafloor magnetic anomalies found in '61 by Raff and Mason (these are reversed-magnetic-polarity stripes, which are embedded in the newly-created seafloor by the Earth's magnetic field, which periodically reverses -- creating alternating stripes which aren't explainable except by tectonic plate theory). This all but cinched it, but it took years for general acceptance to happen -- in '67, my geology prof wasn't yet convinced, and spent a lecture period arguing against it (the students, OTOH, tended to see the light right away, based on the evidence presented). In '68, Pinchon worked out the plate positions, and by the mid-70's, plate tectonic theory was accepted as correct by all but a few lingering die-hards. (It's interesting that similar remnant-field reversals have been discovered on Mars, isn't it?)

Yes, they were interesting times. Overthrow of "established scientific fact" is always interesting, yet it happens often... that's how science progresses, after all. Only some of the time do the revolutionaries get burned at the stake; the rest of the time, they are merely ridiculed in print and reviled in person.

I guess it is the weakest point. When weighing up evidence like this I guess we rely on our own experiences and yours are different from mine. Having worked in string theory related stuff for a few years I know what it is like to have a sceptical audience. But I generally tend to make guarded statements like "Assuming string theory is a good model then...". I would never make a statement like the following from the NASA press release:

METEORITE YIELDS EVIDENCE OF PRIMITIVE LIFE ON EARLY MARS
A NASA research team of scientists at the Johnson Space Center and at Stanford University has found evidence that strongly suggests primitive life may have existed on Mars more than 3.6 billion years ago. (My italics)

I guess that's the difference between your opinion and theirs: they figured they had good evidence, and you figure they don't. Dave McKay (of NASA) still sticks pretty much by the findings, and Kathie Thomas-Keprta (Lockheed Martin) very strongly supports them; time will tell who is right. My point is that science never advances without people going out on a limb with their conviction that a new interpretation is correct, rather than the conventional wisdom. This is not the equivalent of perpetrating a hoax! -- even if they are subsequently proven wrong.

Given the doubt over the interpretation of 'nanobacteria' fossils it seems to me that the most reasonable interpretation of part of this 'evidence' is that it is a demonstration that such 'fossils' can be produced by inorganic processes in a sterile environment but of course you don't get big bucks for a finding like this.

On the contrary: some people are getting funding to disprove the "martian fossil" findings. The ASM link quotes some of them. With any discovery, confirmation or refutation of the findings is critical to its acceptance, and the controversy is the process through which the findings on all sides are integrated by the scientific community; Mari on Anderson's lecture is a good summary of this particular controversy, and concludes (correctly, in my opinion) "The main drawback to this story is the media focus on such sensational news. Media hype may increase public awareness of science, but the problem is that the complexities get lost in the glare of the spotlights." Her last couple of sections are well worth reading.

I think the jury's still out, and I think you're prematurely making up your mind. But, hey, it's your mind -- do with it what you will.

---

... and myself to "Bond, James Bond".

I think a cluster of $1000 iMacs would severely trounce a matchbox cluster. And it's been done before... Read about it here.

Radio antennas give off radiation too - radio radiation. No one worries about radio radiation - there are plenty of people right beside a radio tower - hell, some are built in the middle of cities. Somehow I've got a feeling no one will really care, at least, after a few years of no one dying because of it.

You'd be suprised - see here and this study here.

Yeah, and how many fingerpr ints did these yahoos put all over that mirror? ;>

Here's further information on the this theory. I think it's quite good, myself. Note that New scientist barely scratches the surface of it:

www.physics.adelaide.ed u.au/ASGRG/ACGRG1/papers/cahill.ps

By the way, if one is after wild and wacky theories, as well as pretty damn good ones, you can do worse than check out the pre-print server on xxx.lanl.gov (Uk mirror at xxx.soton.ac.uk) This is one of the oldest sites on the net.

An Australian research team clustered a bunch of iMacs, and the results were sad. Intel and Alpha boxes trounced the iMacs. The iMacs weren't designed for that sort of application, either, but it points out some major problems with using PPC (currently) for that sort of application -- at least on the iMac.

The article is at:

http://www.dhpc.adelaide.e du.au/reports/065/abs-065.html.