Questions in the Science & Nature category.
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August 31

Film of visual proofs of the Pythagorean Theorem shown by Edward Tufte?

In the late 1990s I attended one of Edward Tufte's day-long seminars. Tufte screened several short films for us, including "Mona Lisa Descending a Staircase", "Powers of Ten", and another short presenting a series of visual proofs of the Pythagorean Theorem. There are a variety of such films out there on the tubes, but can anyone help identify which one Tufte is likely to have chosen? [more inside]
posted by Songdog at 4:33 PM - 2 answers

August 30

Solar System geometry - Neptune in solar conjunction

I'm writing an SF story which involves something akin to a space station/industrial complex in orbit around Neptune. I need to know whether Neptune ever goes completely behind the Sun when seen from Earth and if so for how long, or whether the line of sight between Earth and Neptune just grazes the edge of the Sun. [more inside]
posted by Devonian at 10:59 AM - 11 answers

August 29

Weird flower identification

My wife brought home this flower, which looks sort of like a fuzzy ear of corn made out of cotton on some very spiky leaves. Any hints on what it is? I've used online resources to no avail.
posted by eschatfische at 11:43 AM - 3 answers

August 25

What is this small shoreline fish found in surf of MA beaches?

Purchase of a cheap mask & snorkel has shown me that the surf zone of east coast beaches is an ecosystem chick full of crabs & fish & more- totally amazing! Within 2 feet of shore (in surf, not in tide pools) we recently found tiny puffer fish, pipefish & one mystery fish - what is this fish? pic 1 pic 2 (Found all over beaches of Martha's Vineyard. It's about 3 inches long, has wing-like fins that it uses to scoot along the sandy bottom. Some were all light brown, some had a lot more white. Pics look weird as the fish is inside an old 2 liter soda bottle.)
posted by chr1sb0y at 6:36 AM - 4 answers

August 24

Identify the fungus

What is this fungus? [more inside]
posted by hexatron at 2:14 PM - 15 answers

August 21

Physical Sensation When Driving by Electric Utility Fault/Arc?

While driving home from work yesterday afternoon during somewhat-cloudy daylight, I suddenly noticed a bright bluish glow on nearby objects, heard a loud hum that sounded like it had 60/120ish Hz components, and felt a strange tingling/vibrating sensation in my upper body. When I got home, I checked the power company's outage map and saw that there was a ~500-customer outage centered around the area where this happened, which started around the time I drove through the area. The stated cause of the outage was "equipment problem." Because of this, I am guessing there was some kind of fault in the roadside electric distribution system which caused all of this, and I have some questions about what might have happened. [more inside]
posted by Juffo-Wup at 5:48 PM - 9 answers

August 18

Are you a researcher or academic? I want to make neat software for you!

Dear academics who use online questionnaires in your research: help me understand how you get those questionnaires online and go about using them. I want to help make them better. [more inside]
posted by escape from the potato planet at 6:11 PM - 18 answers

Looking for analogy regarding how the brain makes decisions

I read an interesting analogy a few years back about the brain and how decisions are made prior to your consciousness realizing that a decision has been made. It was something along the lines of your consciousness being the queen while something else was doing the real thinking and then convincing the queen it was her idea all along.. Although I think there were three parts at play. Does this ring a bell with anyone?
posted by zeoslap at 1:32 PM - 8 answers

August 17

Is this the aurora borealis?

Do these photos taken on Saturday near Barry's Bay, Ontario show the northern lights? I checked with a compass and they were definitely in the northern part of the sky. To the naked eye, it just looked like vague brightness. Aside from rotation and cropping, these photos are straight from the camera, processed from RAW in Lightroom. [more inside]
posted by sindark at 7:00 PM - 10 answers

Biology books for DIYbio study group?

Our DIYbio group in Toronto recently finished all the chapters with review questions from Molecular Biology of the Cell. We're looking for a new biology book (or books) to tackle. Any suggestions?
posted by clawsoon at 9:52 AM - 7 answers

Did I saw a dinosaur?

Found this footprint shaped hole in a rock at the beach. Is it a dinosaur footprint? [more inside]
posted by popcassady at 8:53 AM - 5 answers

August 16

moon phase and path by specific location

I want to see a graphical representation of the moon and it's phase, elevation and path across the sky for my specific geographical location. You know, watch the moon come up on the right place on the horizon, with the crescent (or whatever) at the right angle, move across the sky at the right elevation, and with time indicators. Want to watch it on my PC. Is there a website, app or whatever (yeah I'm not too computer smart) that will do this?
posted by Jackson at 7:21 PM - 5 answers

Is there a maximum effective dose of psilocybin?

I have heard and read that psychedelics like LSD and shrooms act on serotonin receptors and that once those receptors fill up (either with actual serotonin or antagonists) no additional effect will be felt from taking a higher dose. I would really like to find actual academic references about this, but all I'm seeing is casual comments on message boards, backed up with nothing. Unfortunately, my Google Fu is failing me here and it's driving me crazy. [more inside]
posted by mysterious_stranger at 3:19 PM - 8 answers

August 15

how to measure electricity voltage transforming & surge protectors

I am using 100 volt 50/60 amp electrical devices in a 220 volt country. I have a few 100 watt transformers (100 volt to 220 volt) which are used for individual items. This is working well. I have additional questions regarding voltage transforming and surge protectors. Please join me inside: [more inside]
posted by gen at 7:51 PM - 8 answers

August 13

Size of objects in the Perseid meteor shower

So last night we packed up the car and enacted our yearly late summer ritual of NOT seeing the Perseids, except, breaking with tradition we actually saw something. How big are the objects we saw burning up in the atmosphere? Grain of rice? Tennis ball? VW Beatle? Your Mama?
posted by Keith Talent at 8:52 AM - 4 answers

August 12

Learning To Read Mathematical Notation?

I do not have a math background, but I have been learning statistics for work and while I understand the concepts, I am having a really hard time reading mathematical notation (proofs, formulas, etc). It feels like I missed the 101 class in reading the language of mathematics. Are there particularly good resources out there on reading Mathematical Notation?
posted by Spurious at 1:42 PM - 10 answers

August 11

Fano Plane and Hexagonal Tiling - a deep connection or a shallow one?

I've been chewing on the Fano plane a lot these last few weeks, and have just noticed something that seems really interesting to me. Notably, that the seven lines of the plane map very nicely to the 7-color hexagonal tiling. [more inside]
posted by NMcCoy at 1:24 AM - 10 answers

August 8

How does Super critical CO2 attract?

I've been reading about SC CO2 extraction. CO2 is neutral in charge (as I have come to understand), so I am uncertain how it attracts the stuff (caffeine, cannaboids, antioxidants, et al.) that it draws out in this process. Does the charge change in the fluid state? You don't have to explain it like I'm 5, more like I took Chem 101 a long time ago.
posted by falsedmitri at 7:06 PM - 8 answers

Best dark sky near Harwich on Cape Cod to watch Perseids?

I'm looking for your best dark sky recommendation near Harwich on the Cape to enjoy the Perseid meteor shower this week! Thanks!
posted by eggman at 2:14 PM - 4 answers

August 6

How do you match a paint colour from the past?

My brother-in-law who is a guitarist and guitar collector wants to paint a pre-CBS Fender Stratocaster in the original 'Sonic Blue' colour that the company sold in the early 1960s (used by John Lennon amongst others). The trouble is that if you google this you end up with several different versions of the colour that vary in terms of their blue/green balance, saturation etc. So the question is, without getting into the philosophy of colour perception, is there an easy way to obtain the right colour of paint? [more inside]
posted by jamespake at 4:28 PM - 9 answers

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