Things we'd probably never see if not for the Internet.
Launch of a 21-foot long X-Wing. Apparently they don't make them like they used to, a long time ago in a galaxy far, far away…
From Seth.
Friday, October 12, 2007
Wiki Advice
This article has interesting advice on building a good Wiki. Note that this is about the software, not content.
The author doesn't like CamelCamel case so I strongly disagree on that point. I consider CamelCase not only a good idea but essential. MediaWiki is particularly annoying on this point, though I've decided I can live with it.
The point about good search with relevant results is important, IMHO.
Looking back over it, maybe I only agree with about half of the article but I'll post it here anyway.
The author doesn't like CamelCamel case so I strongly disagree on that point. I consider CamelCase not only a good idea but essential. MediaWiki is particularly annoying on this point, though I've decided I can live with it.
The point about good search with relevant results is important, IMHO.
Looking back over it, maybe I only agree with about half of the article but I'll post it here anyway.
Cartoon: Xkcd
xkcd - A webcomic of romance, sarcasm, math, and language - By Randall Munroe
Someone just showed this to me recently. It's sometimes funny IT humor. I haven't read enough to tell how often.
Someone just showed this to me recently. It's sometimes funny IT humor. I haven't read enough to tell how often.
Thursday, October 04, 2007
Happy 50th Birthday Space Age!
The Space Age is 50 years old today! Wow. Sputnik was launched on 4 October 1957 at 19:28:34 UT.
APOD
Saturday, September 29, 2007
Excellent MythTV Notes and HOWTO
This site seems to be an excellent MythTV HOWTO and collection of notes.
Time Warner Cable ISP and Privacy!
Clark Howard discussed Time Warner's privacy policy on the air on 27 Sep. Here is a quote from his show notes on clarkhoward.com (as linked above). I wonder what Comcast's policy is? (Obviously, I should go and (re!)-read it.
Do you hate legal mumbo-jumbo? Well, consumer reporter David Lazarus recently read through Time Warner's entire 3,000 word privacy policy and terms of service. What he discovered is that Time Warner reserves the right to track the Internet habits of its high-speed customers. This info includes what websites you visit, how long you spend on them and what e-commerce purchases you make. They can also read your personal e-mails, according to the terms of service. Time Warner is also allowed to disclose personally identifiable info about its customers to advertisers, direct mail operations and telemarketers for a price. A company spokesperson claims they're not doing all this just yet, but Clark wonders why Time Warner is even allowed to reserve the right to totally invade your privacy. And it's not only Time Warner that has these kinds of policies -- AT&T tracks very similar info on its customers and records their TV viewings habits. While it's never good to look reflexively to Washington for a solution, Clark believes in this case we need an ironclad privacy policy from Congress to protect the privacy of your viewing and surfing. After all, would the CEOs of Time Warner and AT&T -- or those on Capitol Hill -- like it if the public saw every one of their e-mails?
New Google 411 Service
The new Google voice-recognition 411 service is very cool. Check out the video.
Monday, September 24, 2007
Gmail Unread Mail
Okay, looking on Google groups I found out how to do something I've been needing, wanting, and wondering about for quite a while: How do you search for Unread email?
It turns out that apparently, Unread is a hidden label. So, you can put this in your search field:
label:unread
OR, if you want to search another particular label for unread email:
label:unread label:ImportantMessages
It turns out that apparently, Unread is a hidden label. So, you can put this in your search field:
label:unread
OR, if you want to search another particular label for unread email:
label:unread label:ImportantMessages
Tuesday, September 18, 2007
New Job
I've never posted my biggest news here. After 22 years I left Emory and moved on to new employment. My last day at Emory was actually 20 July 2007, so this post is a little late.
Who's my new employer? You have to ask me for that information.
I'm still in IT, still in Linux, still doing basically the same things at the same level that I was before.
I started the new job on 6 Aug.
Who's my new employer? You have to ask me for that information.
I'm still in IT, still in Linux, still doing basically the same things at the same level that I was before.
I started the new job on 6 Aug.
Monday, September 17, 2007
Tuesday, August 21, 2007
Scale of the Universe
Someone recently posted an article explaining the scale of the universe via various analogies. We do have a hard time percieving a wide range of scales where distance is involved. However, humans seem to have a perception of time that has a large dynamic range. So, I've found the best way to talk about the size/scale of the universe is in terms of light-travel time. (In other words, how long would it take light to travel that distance).
Oh, and you can basically ignore any talk of distances to the farthest galaxies, clusters, or talk about the size of the universe or distance to the edge of the universe. Most of those distances are highly model-dependent, and the concept of distance barely applies. After all, everything is moving on cosmological scales, the universe is expanding. That's all another discussion.
- to the Moon - ~1.25 seconds
- to the Sun - eight minutes
- to Pluto - about four hours
- to Alpha Centauri - about four years
- to Sirius - about eight years
- to the Orion stellar complex - about 1500 years
- to the center of our Milky Way galaxy - 30,000 years
- Diameter of our Milky Way galaxy (visible arms) - 100,000 years
- To M31 the Andromeda Galaxy - 1.5 million years
Oh, and you can basically ignore any talk of distances to the farthest galaxies, clusters, or talk about the size of the universe or distance to the edge of the universe. Most of those distances are highly model-dependent, and the concept of distance barely applies. After all, everything is moving on cosmological scales, the universe is expanding. That's all another discussion.
Tuesday, July 31, 2007
RIP Tom Snyder
RIP Tom Snyder. I always enjoyed the Tomorrow show and later the reincarnation on CNBC. In addition the pretty well-covered history in this article, I thought the tight, close-up shots they used were pretty cool.
Tuesday, July 24, 2007
Python Now
Okay, I've been using Python for a handful of months. I've gotten over the white space as langauge element business. I still don't favor it, but I get it. I personall still prefer braces or something like them for delimiting statement blocks, but I can live with the white space.
There are two unforgivable sins in Python.
The first is that instance variables and method names in an object class definition occupy the same name space! This means you can't have a variable called file and then a method to get/set it cadlled file(). As soon as you write a value to the variable (self.file = something) you've overwritten your method definition! Am I missing something here?
So you either have to use the built in direct access obj.file = something which you can do directly to set (and get), but you've lost the ability to massage data as you set or get it. Or you have to resort to obj.get_file() and obj.set_file(), or a method that does both.
Okay, I forgot what the second one was.
Update 18 Oct 2007: Okay, there is a way. See this post.
There are two unforgivable sins in Python.
The first is that instance variables and method names in an object class definition occupy the same name space! This means you can't have a variable called file and then a method to get/set it cadlled file(). As soon as you write a value to the variable (self.file = something) you've overwritten your method definition! Am I missing something here?
So you either have to use the built in direct access obj.file = something which you can do directly to set (and get), but you've lost the ability to massage data as you set or get it. Or you have to resort to obj.get_file() and obj.set_file(), or a method that does both.
Okay, I forgot what the second one was.
Update 18 Oct 2007: Okay, there is a way. See this post.
Wednesday, July 18, 2007
Crossing the Rings of Uranus
From Sky and Telescope, the Earth will cross the rings of Uranus for the first time since their discovery!
On Thursday, August 16th, Earth will cross the equator and ring plane of Uranus, and astronomers all over the world will be on watch. The unusual geometry offers a unique view of the planet's atmosphere, satellites and ring system.
…
Uranus's orbital period of 84 years means that we get ring-plane crossings only every 42 years. During the last one, in 1965, little was known about the distant planet, the ring system hadn't been discovered, space telescopes sounded like science fiction, and the 5-meter Hale telescope on Palomar Mountain was the world's largest.
Sunday, July 15, 2007
Comet Linear C/2006 VZ13
From Sky and Telescope:
Comet LINEAR (C/2006 VZ13), now crossing through Draco and Boötes, has far exceeded expectations. It was originally predicted to peak in brightness around magnitude 10, a pleasant spectacle for people who enjoy viewing faint comets through telescopes. But the latest magnitude estimates range from 7.5 to 8.0, making it an easy sight through 10×50 binoculars in a dark, transparent sky.
As of July 10th, the comet appears as a bright, round fuzzball roughly 8' across, with little hint of a tail. It will probably peak in brightness shortly after July 14th, when it comes nearest to Earth. Then it should fade gradually until perihelion, its closest approach to the Sun, on August 10th. But it will be disappearing into the evening twilight by the end of July.
Saturday, July 14, 2007
Who's the Emptiest?
So after the amazing web page, Seth and I embarked on a discussion of emptiness, where I claimed:
Which led to an interesting question. Which of these is the emptiest? My first intuition was that the average distance between objects, cubed, would give a rough indication of emptiness. Now, as I write this, it's obvious that emptiness is just density. In this case we're talking about particle density (things per cubic-length) and not mass density (grams per cubic-length).
Here's my first, rambling shot at the question.
Other things, the Solar System, and even galaxies are similarly sparse. I find it fascinating that two galaxies can pass through each other with probably no stars colliding. (Gas, however, is a different matter, uh...so to speak, and gravitational, tidal forces are really, really a different matter!)
Which led to an interesting question. Which of these is the emptiest? My first intuition was that the average distance between objects, cubed, would give a rough indication of emptiness. Now, as I write this, it's obvious that emptiness is just density. In this case we're talking about particle density (things per cubic-length) and not mass density (grams per cubic-length).
Here's my first, rambling shot at the question.
As a start, the Sun is about 100 Earth's in diameter but the nearest star is four LY away which is about 24e12 miles. The earth's diameter is about 8000 miles, right? (I never can remember, but we are headed east at about 1000 mi/hr meaning the circumference is about 24,000 miles and over pi * d gives 8000 as d).
That make the Sun about 8e5 miles in diameter. So the nearest star distance is 24e12 / 8e5 = 3e7 diameters.
The web page you sent says the proton diameter to atom diameter ratio is about 1e5 so that makes a galaxy maybe 300 times emptier [sic] (3e7 / 1e5 = 3e2), or taking it in a volume sense, (3e2)^3 = 9e6 =~ 10 million times emptier. Wow. I wonder if that's right...
Now take the Solar system. If the Sun is 8e5 miles in diameter, we know the earth-sun distance is about 93e6 miles. 93e6 / 8e5 =~ 12e1 = 120. So the Earth is only about 120 solar diameters away so the solar system isn' t nearly as empty as an H atom. By volume 1e5 / 1.2e2 =~ 8e2. By volume (8e2)^3 =~ 6e8 so the atom is 600 million times more empty!
Neptune is at about 35 AU I think so that makes it about 4000 diameters, still less ``empty'' than an atom.
H-Atom Scale Model - 11-Mile-Wide Web Page!
Seth sends this link that is the coolest, most clever, and shocking thing I've seen on the web!! It's a scale model of a hydrogen atom.
It's a relatively simple web page with an electron as a single pixel, a proton as an image 1000 pixels across, and enough pixels between them that, at 72 pixels/inch the web page itself is 11 miles wide!!! That said, at least in Firefox it renders instantly and you can easily scroll to the right where the electron is.
Fascinating!!
It's a relatively simple web page with an electron as a single pixel, a proton as an image 1000 pixels across, and enough pixels between them that, at 72 pixels/inch the web page itself is 11 miles wide!!! That said, at least in Firefox it renders instantly and you can easily scroll to the right where the electron is.
Fascinating!!
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