1

Just Chat! / I hate seasonal references

« on: 11/11/2013 00:00:35 »

Since this is the only forum I'm a member of, I'll use it for my rant. As a southern hemispherer, I HATE when release dates or schedules are tied to a season. "Autumn release", "Due Spring 20XX" for example.

In the age of the internet where pretty much everything is international WHY THE FROG DO PEOPLE STILL DO THIS?!? Drives me mad. Don't people realise that seasons change depending on which hemisphere one is?

Anyway, that's my rant.

2

Physics, Astronomy & Cosmology / do supermassive black holes exist anywhere other than at the centre of a galaxy?

« on: 28/10/2013 02:28:00 »

Is it possible that one might form in a spiral arm for instance? or that a galaxy might have a multitude of "super-massive" black holes?

And while we're talking about it, is there even a scientific description of what one is?

3

Plant Sciences, Zoology & Evolution / How do birds pick up multiple bugs at a time in their beak?

« on: 22/10/2013 02:57:46 »

I was gardening the other day and had a peewee wandering around collecting various small grubs and ants, then flying off.
I noticed it was able to hold several things in it's beak, but then it would peck down and come back up with yet another grub, without dropping the rest.

Does anyone know how they do this? are they just really quick?

4

Chemistry / Can a fire be scaled down to Smurf size?

« on: 19/08/2013 03:29:28 »

I've wondered this ever since watching the smurfs as a child. If a smurf gathered together a bunch of smurf-sized twigs and sticks and scrunched up a bunch of smurf-sized newspapers which they lit with a smurf-sized match...

How big would the flames be? Because if I tried to light a 'campfire' that small it would just burn up in no time.

5

Physics, Astronomy & Cosmology / Does the effect of gravity bend with warped spacetime?

« on: 16/07/2013 06:02:38 »

I was thinking about gravitational lensing and the ability for a large mass (or technically any mass i guess) to bend the light and make an object seem to be from a different direction. I know that the effects of gravity propogate at the speed of light - ie. the gravitational we feel from the sun corresponds to the position we see rather than where it has travelled since the light left.

So. If we see the light from a star during an eclipse that is actually behind the sun, but appears to the side, do we feel the effects of gravity as if it was behind or do we feel the effects of gravity from where it appears.

I realise that for this example, the effects of gravity of a distant star are next to nothing, but does the concept hold? If so, and the gravity propogates in direct lines when light is bent, does that mean that we could possible feel the gravitational effects of some far off thing before the light reaches it?

And more importantly, can we exploit this fact for some sort of faster-than-light communication?

6

Physics, Astronomy & Cosmology / Can air pressure replace gravity?

« on: 18/04/2013 06:53:26 »

I was listening to the ask TNS podcast recently where Ben was discussing the tremendous pressure air puts on us at all times. It made me wonder:
a) would our weight change on a atmosphere-less Earth? and
b) would it be possible to simulate some sort of "gravity" on a space ship by somehow increasing the air pressure on top and decreasing it below.

Actually, just thinking about this as I type, that would just be a really big ceiling fan for a space ship. So now:
b)i) would a really big ceiling fan on a space ship put enough pressure on bones to reduce the osteoporosis (spelling?) suffered by astronauts?

7

Just Chat! / Star Wars. LIVE!

« on: 12/04/2013 02:08:48 »

If the events of Star Wars happened a long time ago in a galaxy far, far away, does that mean if we had a good enough telescope, that we could watch it be played out before our very eyes?

8

Physiology & Medicine / Is it possible to completely relax all our muscles?

« on: 03/04/2013 03:21:17 »

I've heard that muscles either contract, or relax but we can only create movement by contracting a muscle. So..
a) Is this correct?
b) If so, what would we look like if all of our muscles were relaxed at the same time?
c) What would happen if someone managed to simultaneously contract all their muscles at the same time? (I have an image of horrible muscle damage due to all the muscles pulling away from eachother).

9

General Science / Is there any reason for parents to make their children eat crusts?

« on: 03/04/2013 03:15:13 »

If we're talking about regular white bread, surely the crust holds no more nutritional value than the rest of the bread. So why make kids eat something that is the same as the rest but a bit chewier and (for some) unpleasant to eat?

I know the crusts give you curly hair, but is that the only reason?  []

10

Marine Science / Does anything eat whale sharks?

« on: 18/03/2013 05:13:24 »

This came from my 5 year old son. I know there are bigger beasts in the ocean, but would they bother with a whale shark?

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Physics, Astronomy & Cosmology / What comes first? The comet or the tail?

« on: 18/03/2013 01:06:54 »

I'm led to believe that the comet's tail is caused by the solar wind heating the surface and turning the ice into vapour. The pop-culture view is that of a tail streaming out behind a comet as it hurtles through space.

Now, this seems obvious while the comet is heading towards the sun, but what happens when it is on it's way back to the outer solar system? Is the tail still behind the comet's direction of travel, or does it continue to be pointing away from the sun, in which case, the comet would actually be travelling through it's own tail?

12

Physics, Astronomy & Cosmology / How is an absolute reference for GPS maintained?

« on: 13/03/2013 23:37:30 »

After skimming through a slightly related post, I find myself wondering how GPS satellites (is that a tautology?) know where the lines of lattitude and longitude are. It seems possible for the equator to be the most stable baseline, but how is that measured? And what about lines of longitude? If there is a slow but measureable shifting of all landmassess, how can we establish a permanent reference point?

13

New Theories / Nostalgia - a by-product of crazy teenage hormone-induced emotions?

« on: 18/02/2013 05:31:13 »

I often find myself inexplicably emotional when remembering days of old. I'm not that old now (early 30s) so "days of old" are really my teenage years.

Music is something that often brings back old feelings and emotion, and it was something that was integral to my life in my teens. I remember being obsessed with bands and wanting to hear them over and over again marvelling at the fact that I never seemed to get bored, or the emotional highs the music gave me never went away.

Then I grew up, and I don't think I'll ever feel as passionate about a band as I did when I was younger. Is this something to do with what's going on in teenager's brain during puberty?

Could nostalgia simply be that our memories of our childhood have been tampered with by teenage hormones and thus give us the illusion that our past was emotionally richer than it is now?

14

General Science / What happens to combed hair?

« on: 17/02/2013 23:08:28 »

Okay, I wasn't sure how to condense this question into a snappy question, but what I'd like to know is that when we comb our hair, I have heard that the comb strips electrons off the atoms in the hair and then some other stuff happens and you get a shock when you touch the metal door frame.

How can electrons be stripped off something without changing the structure on an atomic scale? Is hair still "hair" after combing it?

15

Geek Speak / How does a computer generate a random number?

« on: 15/02/2013 04:15:08 »

Or how does my ipod decide what order to play songs when I "shuffle"?

Is it truly "random" or is there always a pattern?

16

Physiology & Medicine / Why do I find breathing difficult when I have a cold shower?

« on: 13/02/2013 09:30:11 »

It doesn't seem to be a problem with asthma or any sort of condition, it's just that when I stand under the cold water in the shower, I have to breath deeply through my mouth and I feel short of breath.

Does anyone else get this? Any ideas why?

17

Physics, Astronomy & Cosmology / Is there a minimum orbital radius?

« on: 07/02/2013 02:22:41 »

Is a stable orbit acheivable at any distance, or is there some fundamental reason why something really fast couldn't orbit at, say 100m of the surface of the Earth (other than the obvious buildings and terrain limitations)?

18

General Science / What is the difference between electrons and photons?

« on: 06/02/2013 23:29:44 »

I've never really understood the relationship between electrons and photons. I'm told that electricity is the flow of electrons through a circuit, however I'm also told that the electro-magnetic force is quantised (is that the right word?) by the photon.

When I hear science fiction stories about advanced societies harnessing the power of light for all their technological needs i think, isn't light just a form of electro-magnetic radiation and therefore electricity? But then how does the electron fit?

19

Physics, Astronomy & Cosmology / Does light have harmonies and octaves?

« on: 20/01/2013 22:29:34 »

I recently learned (on this forum) that the primary colours are merely just based on what frequencies our eyes pick up the best, and hold no intrinsic value outside our anatomy.

I always thought that harmonics and octaves etc. are intrinsic properties of waves and are true regardless of what the ear's anatomy can detect.

a) Am I wrong?
b) Are there any equivalent properties of light that would be true regardless of the aparatus used to detect and analyse it?

20

Physiology & Medicine / How do immune cells "learn" how to fight infections?

« on: 17/01/2013 04:27:47 »

My understanding thus far...

At some stage, our immune system comes up against a bug that it has never seen before and somehow makes antobodies to combat it. These antibodies stay in our system so that the next time we get the same bug, our immune system already "knows" how to fight it.

What's the mechanism by which these antibodies are created? Is it just trial and error or are there some sort of immune stem cell that can change into any antibody you like?