Stream of Stuff

[owlice]

Python is a programming language that is very popular with astronomers. Here's a good place to start: http://software-carpentry.org/v4/python/

ETA: There's also this: https://developers.google.com/edu/python/

[Chris Peterson]

I want to begin to understand what you guys are talking about when you are discussing computers (e.g.s at random: writing code, python, anti-aliasing fonts, WINE) : have you any thoughts on where I might start?

There are two questions there. For something like anti-aliasing fonts, just ask when you hear a term you don't know. This is just a piece of information, like a million other things discussed in this forum. (FYI, as you know, a display is made up of discrete pixels. When you draw a shape- a line, circle, character- its edges will be "pixelated", that is they will deviate from the smooth shape you'd expect. The lower your screen resolution, the more obvious the pixelation. Anti-aliasing is a trick that fills in surrounding pixels with intermediate color or intensity values to smooth out that effect. As is usually the case for technical subjects, Wikipedia has a nice article. You can turn the anti-aliasing of fonts on and off and compare the difference. The method used in Windows is called ClearType, and is manageable in the Display Properties. It's on by default, because even though it very slightly fuzzes out writing, most people consider that preferable to the jagged little characters you get otherwise.)

The same advice for Wine: read the Wikipedia article. You can almost never go wrong with Wikipedia as your first stop when it comes to technical subjects. (Wine is an emulation tool that lets you run some Windows apps under Linux.)

As to programming, that's very different. What is your learning style? I recognize at least three- learn by taking classes, learn by reading books or other material, learn by doing. I'm in the the third category, aided by the second. If you Google "learning programming" you'll be inundated with online resources, including courses, guided tutorials, and reference material. If it suits your style, I'd suggest walking through some tutorials. Programming is not difficult, doesn't require any math (although some specific programs might), and is more of an exercise in breaking down a problem into very small bits. If you think logically, programming is likely to come naturally.

All computer languages are fundamentally similar, looking different mainly on the surface. Languages can be implemented two ways- compiled or interpreted. Compiled languages require you to write the program, then convert it into something executable with another program. They generally provide the most efficient results, but are harder to test and debug. Interpreted programs run directly from within their development environment (or directly from within the operating system, in which case they are called "scripts"). These days, languages may be a sort of hybrid between compiled and interpreted, as well.

If you follow a tutorial, you can use whatever language they recommend. Python is a popular interpreted language. It's supposed to be easy, although personally I don't like it and think it has ugly syntax that is hard to read. I prefer languages in the style of C, such as PHP, Java, Javascript, C#. But it really doesn't matter that much. If you get serious about programming and want to engage in a complex project, I'd recommend the Microsoft Visual Studio environment. A very powerful version is freely downloadable and includes C++ (try to avoid), C# (superior), Visual Basic (superior). Your Windows machine already includes Javascript and PowerShell interpreters, so you could start programming in either of those right away, again just following online tutorials to get you going.

[MargaritaMc]

Very many thanks, Nitpicker, Owlice and Chris for your really helpful replies. I appreciate them very much indeed.

After I'd posted my initial query, I did some serious googling and the search came up with this course:
http://ocw.mit.edu/courses/electrical-e ... pring-2011 . I've downloaded the written course material and will preview it over the next week or two.
Like the other courses offered by OCW at MIT, it is available free and to do at one's own pace.

This is helpful, as I won't want to begin it, or any other venture, for the time being, as I'm just beginning the Calculus course (also from OCW MIT) and will want to stay focused on that for a while without distractions... I'm not totally sure that I've got all the background necessary for beginning calculus, and am doing rapid revision of pre-calculus before undertaking it in earnest.
The course is only an introduction called The Highlights of Calculus and I was encouraged by the first lecture. (The lecturer, Professor Strang, is an utter gem. I continue to be flabbergasted at the generosity of institutions such as MIT in providing such marvellous free courses. Clearly, one gives a grateful donation, but that is not the point.)

From what nitpicker said, focusing on honing my mathematical abilities will be helpful when I take up learning to program. I can see that: I am thoroughly enjoying the way that doing mathematics is training my ability to think in a disciplined, focused manner. Indeed, my husband (himself a scientist), feels that, having reached my sixties, I've finally discovered, in Astronomy and Maths, what I really love. The years of being a social worker are fading fast!

Margarita

[geckzilla]

Because of the football shape discussion in the other thread, I started looking up lapidary shapes and ended up finding this:

Click to view full size image

Photo and gem cut by Richard P. Homer

At some point Pat and I were looking at engagement rings and I decided they were all incredibly boring. At one store, I suggested that I would like an alexandrite gemstone and was scoffed at by the sales person because "those are too expensive" (along with a rant about how they are only mined in Siberia once a year or something) but they are cheap if you get them created, which I was also scoffed at for even suggesting such a thing. Way to make a sale, buddy. Anyway, I'm definitely not above created gems (it's all star stuff to me!) but the stuff for sale is still so pedestrian. After seeing what can be done I have clearly been to the wrong stores.

[neufer]

[b][color=#0000FF]Tourmaline is notable for exhibiting strong pleochroism.[/color][/b]

---

<<Pleochroism is an optical phenomenon in which a substance appears to be different colors when observed at different angles, especially with polarized light.

Anisotropic crystals have double refraction of light where light of different polarizations is bent different amounts by the crystal, and therefore follows different paths through the crystal. When the mineral is observed at some angle, light following some combination of paths and polarizations will be present, each of which will have had light of different colors absorbed. At another angle, the light passing through the crystal will be composed of another combination of light paths and polarizations, each with their own color. The light passing through the mineral will therefore have different colors when it is viewed from different angles, making the stone seem to be of different colors. Pleochroism is an extremely useful tool in mineralogy for mineral identification, since minerals that are otherwise very similar often have very different pleochroic color schemes. In such cases, a thin section of the mineral is used and examined under polarized transmitted light with a petrographic microscope.

Tetragonal, trigonal and hexagonal minerals can only show two colors and are called dichroic. Orthorhombic, monoclinic and triclinic crystals can show three and are trichroic. For example hypersthene, with two optical axes, can have red, yellow or blue appearance when oriented in three different ways in three-dimensional space.>>

Purple and violet

• Andalusite (strong): green brown / dark red / purple
  Corundum (high): purple / orange
  Hypersthene (strong): purple/orange
  Spodumene (Kunzite) (strong): purple / purple / clear / pink
  Tourmaline (strong): pale purple / purple

Blue

• Cordierite (very strong): orthorhombic blue brown / yellow / greenish brown / gray blue / blue to purple
  Alexandrite (strong): Dark red-purple/orange/green
  Apatite (strong): blue-yellow/blue-colourless
  Benitoite (strong): colorless / dark blue
  Corundum (strong): violet-dark blue / light blue-green
  Iolite (strong): colorless / yellow / blue / dark blue-violet
  Tourmaline (strong): dark blue / light blue
  Zoisite (strong): blue / red purple / yellow green
  Zircon (strong): blue / clear / gray

Green

• Alexandrite (strong): dark red / orange / green
  Andalusite (strong): brown green / dark red
  Corundum (strong): green / yellow green
  Emerald (strong): Green / Blue Green

Yellow

• Hornblende (strong) light green/dark green/yellow/brown

Brown and orange

• Corundum (strong): yellow brown / orange

Red and pink

• Alexandrite (strong): dark red / orange / green
  Andalusite (strong): dark red / brown red
  Corundum (strong): violet red / orange red
  Tourmaline (strong): dark red / light red

Art Neuendorffer (Alexandrite, Virgin.)

[MargaritaMc]

Because of the football shape discussion in the other thread, I started looking up lapidary shapes and ended up finding this:

Click to view full size image

Photo and gem cut by Richard P. Homer

At some point Pat and I were looking at engagement rings and I decided they were all incredibly boring. At one store, I suggested that I would like an alexandrite gemstone and was scoffed at by the sales person because "those are too expensive" (along with a rant about how they are only mined in Siberia once a year or something) but they are cheap if you get them created, which I was also scoffed at for even suggesting such a thing. Way to make a sale, buddy. Anyway, I'm definitely not above created gems (it's all star stuff to me!) but the stuff for sale is still so pedestrian. After seeing what can be done I have clearly been to the wrong stores.

That is beautiful. I'm not into jewellery (my engagement ring sits in its box), but I liked this one, too.
[img2]http://www.concavegems.com/GemPics/6963 ... rgazer.jpg[/img2]

I think I'd wear that one if I had it...

[geckzilla]

Here is a cool combination of scientific disciplines: High energy physics and entomology.

VIDEO: Watch Muscles Move in 3-D Inside a Flying Insect
More info: http://blogs.discovermagazine.com/d-bri ... zL4NYWa__k

Click to play embedded YouTube video.

[neufer]

Here is a cool combination of scientific disciplines: High energy physics and entomology.

VIDEO: Watch Muscles Move in 3-D Inside a Flying Insect
More info: http://blogs.discovermagazine.com/d-bri ... zL4NYWa__k

Shouldn't this be in the "Cute stuff goes here; you have been warned!" thread

[geckzilla]

There are a lot of cute insects but even I am strained to find cuteness in blowflies.

[Chris Peterson]

There are a lot of cute insects but even I am strained to find cuteness in blowflies.

As in many species, cuteness diminishes with age. Actually, with blowflies, it's only the maggots that are cute... especially when they poke their little butts out of skin lesions as they delicately nibble on the underlying tissue.

[geckzilla]

There is virtually nothing more revolting... man, the other day I was telling Pat about fly strike and then for some reason something at dinner reminded him of it and he had to bring it up right then and there. At least I was at my last bite already.

[Chris Peterson]

There is virtually nothing more revolting...

Oh, that's a dangerous assertion. Some might even take it as a challenge...

[geckzilla]

Ok, but we need to use spoiler tags for those sensitive souls out there.

What is more revolting than maggots in flesh? I mean, this includes the frigging botfly. You could loosely throw in the nematode parasites with that. That's pretty abhorrent.

[MargaritaMc]

Ok, but we need to use spoiler tags for those sensitive souls out there.

What is more revolting than maggots in flesh? I mean, this includes the frigging botfly. You could loosely throw in the nematode parasites with that. That's pretty abhorrent.

I'm married to a parasitologist! The gruesome stories I've failed to prevent him telling over dinner (during what was meant to be a romantic candlelit restaurant meal for example) mean that I am totally inured to "revolting"

He has books with photographs too... (We need a barfing emoticon, geckzilla!)

M

[geckzilla]

Haha, lovely. I'd like to say the same has happened with me since Pat does nearly the same thing with random enterology horror stories (he's not even an enterologist but C. difficile is on every intensivist's mind), but my appetite is more sensitive than I'd care to admit. I could probably grab a handful of maggots if I needed to but for some reason if someone brings up an inappropriate topic over dinner it bothers me. I think it's very rude.

[MargaritaMc]

Haha, lovely. I'd like to say the same has happened with me since Pat does nearly the same thing with random enterology horror stories (he's not even an enterologist but C. difficile is on every intensivist's mind), but my appetite is more sensitive than I'd care to admit. I could probably grab a handful of maggots if I needed to but for some reason if someone brings up an inappropriate topic over dinner it bothers me. I think it's very rude.

I have to hang my head in shame and confess to joining in with Top The Ghastly Story competitions back in my social worker days... The worst/best people for this competition included, of course, medics and nurses, but even better/worse were cops! The "URGH!!" factor amongst police tales was very gross
BUT - this would be in the pub over a pint after work, NOT at the dinner table!
Paul, by the way, now keeps parasites and meal times separated I'm glad to say.
M

[MargaritaMc]

I'd read the Guardian article a couple of days ago but the significance hadn't struck until watching this clip from the BBC on YouTube.

Click to play embedded YouTube video.

The Guardian: Crows' reasoning ability rivals that of seven-year-old humans

Margarita

[Chris Peterson]

I'd read the Guardian article a couple of days ago but the significance hadn't struck until watching this clip from the BBC on YouTube.

The Guardian: Crows' reasoning ability rivals that of seven-year-old humans

At which point, the reasoning ability of many, perhaps most humans begins to be systematically wiped out by special interests, leaving the crows well ahead.

[MargaritaMc]

I'd read the Guardian article a couple of days ago but the significance hadn't struck until watching this clip from the BBC on YouTube.

The Guardian: Crows' reasoning ability rivals that of seven-year-old humans

At which point, the reasoning ability of many, perhaps most humans begins to be systematically wiped out by special interests, leaving the crows well ahead.

Mmmm. I didn't like to say, but the reasoning ability of the crow in the video FAR exceeds that of many humans that I know...
M

[neufer]

Click to play embedded YouTube video.

I'd read the Guardian article a couple of days ago but the significance hadn't struck until watching this clip from the BBC on YouTube.
The Guardian: Crows' reasoning ability rivals that of seven-year-old humans

At which point, the reasoning ability of many, perhaps most humans begins to be systematically wiped out by special interests, leaving the crows well ahead.

Mmmm. I didn't like to say, but the reasoning ability of the crow in the video FAR exceeds that of many humans that I know...

[MargaritaMc]

May I be so bold as to draw attention to this new thread in the Handbook?
http://asterisk.apod.com/viewtopic.php?f=28&t=33201

It only has had 25 views as of just now. It points to a SPLENDID article about Apod and how it is edited!

Margarita

[geckzilla]

Norwegians, skydiving, and a meteor. I'm a little dubious but the geologist seems certain!

Click to play embedded YouTube video.

Seen at http://www.universetoday.com/110963/nor ... t-on-film/

[Chris Peterson]

Norwegians, skydiving, and a meteor. I'm a little dubious but the geologist seems certain!

Click to play embedded YouTube video.

Seen at http://www.universetoday.com/110963/nor ... t-on-film/

The video looks pretty good (not like most meteor hoaxes and fakes... and there are quite a few of those). Of course, the extreme improbability of the event should make anyone skeptical. The geologist doesn't know too much about meteorites, but not many do.

In the absence of anything obviously problematic, I'm reserving judgment. Most of the amateur meteorite community thinks it's a fraud, but they've seen a lot of that. Of course, the story came out awfully close to April 1, and everybody on the video does seem to find things very amusing.

[geckzilla]

That is in direct opposition to what is noted in the article at NRK:

“The film caused a sensation in the meteorite community. They seemed convinced that this was a meteorite, perhaps I was the one who was the most sceptical.”

Hmm. It seems like a tough nut to crack. One thing that seemed obviously wrong to me is where the geologist says it would have cut the skydiver in half if it had struck him. It could probably break his back, but I have a very hard time believing there's enough force in that thing to cut him in half or even put a hole through him especially with his conservative estimate of it moving only 300 kph. This is not that much faster than the velocity of the skydiver himself. Why would he say that?

[neufer]

I'm with Chris on this one.

The friend Jon Vegard was, in fact, along the direct path of the stone
that he dropped/tossed beneath him (but only after he was quite
sure that it wouldn't hit the extremely well helmeted Anders).

The only real meteorites that I know of with nice flat well cleaved sides
only got that way after having landed on Earth.