What?! Are you serious?

Pretty much everything I said was wrong? How do you figure that?

Here’s my primary claim: “This article is debunking the idea that there are probiotic benefits to eating dirt, which isn’t what we’re talking about at all”

My claim was that the page you linked is clearly talking about digestive health, not the immune system.

Let’s look at the first sentence in the header

Will eating dirt improve gut health?

I’d say that’s pretty clear. But wait, that’s not the whole header, what does the rest of it say?

According to the Hygiene Hypothesis, ingesting dirt will strengthen our immune system right?

So it’s worse than I thought, immediately, right off the bat, this page is already jumbling the concepts of digestive health and immune system. Just odd.

Look, I’m perfectly willing to concede that there are no real digestive benefits to eating dirt. But then I never made that claim. I have no idea what your motivation is, but you should stop spreading misinformation.

Don’t infections lead to producing antibodies?

This article is debunking the idea that there are probiotic benefits to eating dirt, which isn’t what we’re talking about at all. We don’t care about the beneficial bacteria, they don’t build your immune system, they’re irrelevant. It states right at the beginning that there are harmful pathogens in dirt, which is exactly the point. Those harmful pathogens are literally the only thing that can build the immune system.

You should read Ministry for the Future. It’s about how people cope with the world after the effects of climate change get out of hand. It’s sobering.

The idea of just blowing up the offending petrol infrastructure made me think of it.

Audio is inherently analogue, but you can record it into digital formats just fine.

It’s tempting to say “well, that’s different though” but it really isn’t.

Just like with audio, you’ll need high enough fidelity encoding to make it all work, otherwise you end up with garbage.

Well there is no “data” per se, there’s voltages and a wiring map. And this article is talking about having the complete wiring map.

The neurons deliver electrical pulses across synapses. The thickness and length of the synapse can affect the voltage or amplitude transmitted across to the next neuron. And again, if we have this fairly complete map of synapses, we may have enough information to calculate the electrical outputs of each neuron when it fires.

My understanding is that neurons work something like transistors, they receive signals and when triggered by a strong enough signal, or by enough simultaneous signals, that neuron will also fire and transmit down its synapses. With this alone you absolutely have enough structure for very complex decision making, much like a microprocessor.

I guess the question is really how accurate is this map? If we have a clear enough picture of every synaptic connection, we could simply simulate behavior in software…

So can we model this now?

Can we use this data to essentially emulate a fruit fly’s behavioral patterns?

Like can we just wire this up in a software neural network, feed it some inputs, and see what happens?

So it’s printed on plastic, how’s that for dissipating heat?

We can already make processors pretty small, and we could make them in a lot of different form factors, but heat management is probably the trickiest part.

Or maybe the advantage is not having to counter any sail movement with gyroscopes… which cost energy too.

I think you nailed it right there.

Well that’s a really interesting application though… 9 times less thrust may not actually be a very big deal. A solar sail probe would likely be a lot lighter than a fueled equivalent, so that means you have the payload mass to send more probes on the same launch. And asteroids don’t have meaningful amounts of gravity, so you can take as long as you want to get from one to another (you don’t need much thrust to overcome their gravity well). So yeah, I think more than likely you could make up for a lack of speed with sheer quantity.

That’s such a badass design, I love it.

A variable thrust and thrust vectoring propulsion system with no moving parts. I doubt that’s ever been done before…

Yeah, we may well end up seeing a lot more use of solar light pressure to orient spacecraft over the coming years, especially deep space probes and higher orbit satellites. Telecom satellites need a lot of power for their transmitters, so they generally have quite large solar arrays, I wouldn’t be surprised to see some of those using this method for station keeping. (Though these days they’re already using very efficient ion thrusters for station keeping, so they may not really need to use this method)

But while solar sail propulsion takes a lot of very specific design requirements, using solar pressure just for maintaining orientation doesn’t actually require any fancy hardware (if you already have solar panels), it’s all an entirely software solution. Which means it’s always a viable backup plan when hardware failures occur.

Well… I’m afraid I’m not sure if they’ll be effective for the ISS. The ISS sits in low orbit (a relatively high part of Leo, but none the less), so it hits some extremely thin atmosphere, which has a noticeable drag over time. For that reason the ISS has to boost its orbit a little every few months. My fear is that a solar sail large enough to have an effect on the ISS is probably large enough to add a whole lot of atmospheric drag, even from just the trace particles it encounters.

Maybe someone can answer me this: I’ve always wondered if a solar sail can only generate momentum away from the sun or if it can be angled to create momentum in other direction.

Yeah, 100%. You can totally steer and control your orientation with a solar sail. This is one of the rare actually intuitive things when it comes to spaceflight. (with physics in space It seems like nothing actually works the way you’d expect it to, but this basically does)

We actually have some experience controlling orientation with “solar sails” too. I remember one example of a spacecraft which long after finishing its official mission was left to tumble out of control. Years later, some engineers were able to regain control, use the last of its propellant to counter its tumble and then keep it oriented correctly using only its solar panels as sails, light pressure was carefully controlled to keep the spacecraft oriented.

I believe this is one of those things that benefits from scale. Theoretically, the larger you make the sail, the better the thrust to mass ratio you can achieve (even before calculating a better payload mass to sail mass ratio). With improved materials, we can make stronger and lighter sails and support structures, and this will in turn result in higher velocities by the time the vehicle has left the effective range of the sun. I think speeds truly approaching c are unlikely, but they can still achieve “really freaking fast”.

But then new advanced materials could also change that, we’re developing metamaterials with some fascinating properties, carbon nanotubes are just the tip of the iceberg. Who’s to say that we couldn’t some day achieve those speeds.

Doesn’t “solar wind” refer to the physical particles emitted from the sun? Like hydrogen, helium, etc ejected from the sun’s outer layers?

My understanding is that the solar sail is propelled mostly by the photons themselves, not the atomic particles that may also be reaching it.

Of course this probably doesn’t change your argument at all, since the intensity of light drops off precipitously as you fly further and further from the sun.

Ok, a side note on etiquette here.

When I saw this reply it had a point score of 0, which means somebody downvoted the post.

When a user is freely admitting a lack of expertise, and defers to another user who seems to know better, I would say it’s extremely rude to downvote that reply.

This is an example of a user going out of their way to humbly rescind their previous statements when it appears they were mistaken (this is admirable and not a thing that usually happens on the Internet). They didn’t do it for their own benefit, but for the benefit of the community, to not leave misleading or incorrect information in the comments.

So to sum up, downvoting a selfless act is pretty shitty and not good for the community.

Although, I think our theories say that most planets have an ocean of molten rock at some point in their creation, right? Isn’t that part of the planet creation process?

Though of course, finding actual evidence to support those theories is always good.

That’s what it says!

Not so much conducive to life, but it’s still an ocean!

then our model of physics is totally fucked

Aren’t we discovering that all the time? We’re just making the most of the best models we have, but we know for certain that they’re very incomplete.