Science questions not worth a thread I: I'm a moron!

hobbsyoyo said:

In space, don't know the velocity of the gas flow yet (the system is still being designed). This would be used while under acceleration so we may be able to separate the soot via it's higher density.

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I can't explain as well as I'd like. And can't draw worth a damn at all.







So the gas goes in, then the intake widens to reduce velocity. It sprays down into a settling tank, and the lighter gas is pushed up to the top where many tiny holes let it out.

uppi said:

I can think of three effects that could be a problem:
1) Redshift: As space is expanding, the signal will be shifted to lower frequencies. A lower carrier frequency has less bandwidth, so a densely coded signal might lose information.
2) Attenuation: At large distances, any signal will decrease in intensity with one over the square of the distance. At interstellar distances, you would have to start out with a huge signal so that you can recover a tiny amount of it.
3) Dispersion: Although space is mostly empty, it still has some matter that amounts to a tiny amount of dispersion. If the signal travels long enough through a dispersive medium, it will lose information.

So no, a signal emitted by aliens is not guaranteed to be recognizable when it reaches us. How much a signal is degraded and by what effect is probably specific to the signal and the exact nature of the space in between, so I do not think there is a general answer.

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Over interstellar distances, would gravity, gravitational lensing like effects, distort the waves enough to make them incoherent?

Cutlass said:

Over interstellar distances, would gravity, gravitational lensing like effects, distort the waves enough to make them incoherent?

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They could. But I would guess, unless the waves pass an extreme gravitational gradient, you have a huge detector, or you are in exactly the wrong spot, the effect would not be that big.

I haven't really read most of the posts regarding Hobbsyoyo's question, but I just want to remark how crazy it is that an aerospace engineer asks for help with aerospace engineering on this video game forum

Lohrenswald said:

I haven't really read most of the posts regarding Hobbsyoyo's question, but I just want to remark how crazy it is that an aerospace engineer asks for help with aerospace engineering on this video game forum

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You never can tell where brainstorming will come from. And while CFC OT is at a low ebb for brainpower, there's still a hell of a lot here.

Lohrenswald said:

I haven't really read most of the posts regarding Hobbsyoyo's question, but I just want to remark how crazy it is that an aerospace engineer asks for help with aerospace engineering on this video game forum

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Cutlass said:

You never can tell where brainstorming will come from. And while CFC OT is at a low ebb for brainpower, there's still a hell of a lot here.

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This. I'm at the purely brainstorming phase of problem solving - and it's the kind of problem that a) isn't taught in textbooks and b) no one else in my lab has experience with. So why not widen my search avenues to get some early feedback to trim back the literal infinite possible solutions down to a few that have a chance of being workable? And as Cutlass remarks, this forum seriously over-performs in the brain department which is part of the draw for me.

@Cutlass- yeah, I got your point before you posted the drawing and I think it may work because the whole system would be under acceleration. Thanks!

Thanks, uppi!

You could use some kind of separator wheel (in German they are called Sichterrad)

The gas with the soot will come from the outside and tries to enter the spinning wheel to leave the container. Due to the centrifugal forces the air separator wheel will keep all soot above a certain size out of the wheel. The particle size can be adjusted by a variation of speed and size of the lamellas. Air separator wheels are usually used to separate grounded from ungrounded particles in powder mills (e.g. from Netzsch) but should also work for your application.

Thanks, I will look into them!

Perhaps more a mathematical question than a scientific one, but I feel people here are probably best placed to comment. The news came out today that bacon, ham and sausages are carcinogenic - specifically, that eating two slices of bacon (50g) per day increases your risk of colorectal cancer by 18%.

I had a look at some of the numbers. 41,600 people per year are diagnosed with colorectal cancer in the UK, 95% of whom are over 50. 65 million people live in the UK, of whom about 21 million are over 50. This means that, on average, you have a 0.0047% chance per year of getting colorectal cancer before you are 50, which works out to 0.24% over the fifty years. Assuming that you then live for another thirty years, you have a 0.19% chance per year of getting it, which works out to 5.7% overall.

Assuming that these are the rates (which they aren't) for people who eat no bacon, sausages or ham at all, we know that they increase by 18% for people who eat a relatively large amount of the stuff. This means that, if you eat two rashers of bacon a day, every day, until you turn fifty, you have not a 0.24% but a 0.28% chance of getting colorectal cancer before your fiftieth birthday. If you carry on doing this until the age of eighty, you then have not a 5.7% chance but a 6.7% chance of getting it. By my reckoning, this means that changing consumption habits will affect 4 under-50s out of 10000, and 100 over-50s. For the other 9960 under-50s and 9900 over-50s, it will make no difference.

I suppose the overall question is as follows: is this all a big fuss over nothing?

Flying Pig said:

[SNIP] some maths that may or may not be correct.

I suppose the overall question is as follows: is this all a big fuss over nothing?

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I do not want to comment on your sums, but the beeb says:

Estimates suggest 34,000 deaths from cancer every year could be down to diets high in processed meat.

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Which assuming this is global then your chance of dying from this is about 5 in a million per year, which I would say approximates to "a big fuss over nothing".

The chances of getting a cardiovascular disease from living on a high fat diet (like lots of processed meat/bacon) are probably much worse than getting colon cancer.
I am also not sure if every polypus, as a lot of them are easily removed during the diagnostic screening are already considered colon cancer.
Also colon cancer has a huge genetic factor (between 5-30% of all colon cancer cases) i.e. inheriting it from ancestors is quite probable compared to other diseases.

I would think many people eat 50g of processed meat a day, so the current rates already contain a lot of bacon eaters, and the bacon-free cancer rate would be lower than the current average rate.

i'd rather die at 75 eating red meat than die at 85 eating kale.

Bacon is my biggest processed meat vice, but I only eat it 3-5 times a month, mostly when I'm traveling.

madviking said:

i'd rather die at 75 eating red meat than die at 85 eating kale.

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I think it does come down to that, at some level. If we believe the news, we can extend our lives by a few years by avoiding just about everything that makes them interesting, but I'm not sure I'd want to.

yea as great as it would be to live for really long, you're getting way into diminishing returns by the time you're 75-85.

If eating kale makes you miserable, I doubt if that is healthy either then.

That's a great point.

It isn't really an either or case.