Dick Tracy’s communicator watch actually seems pretty shitty by today’s standards. His didn’t have a high def LCD screen in it.
Star Trek’s PADD also seems obsolete by real world standards. Those were just e-readers. A tablet is an entire computer, and a smartphone is an even smaller, pocket size computer. There are even phones and devices that connect to phones that do tricorder like scanning of vital signs, the atmosphere, even analyzing the elements that make up an object through spectrographic analysis. Meaning we have the ability to combine the ship computer, a PADD and a tricorder into one device.
Well, the Tricorder had very advanced scanning capabilities. We can’t diagnose and cure cancer with a handheld device yet, but I did get some viral and bacterial tests done in a manner of moments by some desktop lab equipment the other week, so we’re definitely getting there.
Toothbrushes were mentioned, and I'd assume that the toothpaste does a good enough job at killing bacteria that it doesn't make a difference, aside from that the bacterial load is probably low enough to be negligible.
But yeah, you don't want to be thinking about putting a pooey stick in your mouth either.
I mean, we still CLEAN our toilets when they’re still just visibly stained with hard water or whatever causes rings and whatnot, so I can see the feeling better about being a huge component
This isn’t exactly a ‘science debate’ but I’ve met several people that still think the ‘Great Wall is the only man made object visible from orbit.’ I read somewhere that may come from a dream some Chinese king had like 1000 years ago.
Almost crazier than flat-Earth in terms of being easily disprovable just by thinking about it for 20 seconds, but people have stated that to me as a fact and were kind of incensed when I explain it’s obvious nonsense.
Using your choice of words it would be “stable/static”. Effects of gravity moves at the speed of light. Perhaps a better example would be Earth orbiting the Sun.
The Earth is 8 light minutes away from the Sun. Meaning, the sunlight we see on Earth at this exact second left the Sun about 8 minutes ago. If we wave a magic wand and make the Sun blink out of existence in a fraction of a second, the Earth would continue to orbit the, now non-existent, Sun for the next 8 minutes. After 8 minutes the Earth would stop its circular orbit and head straight out of the solar system at what ever direction it was traveling at the end of the 8 minutes.
That’s amazing, thank you! A ghostly remnant of gravity still exerting 8-ish minutes of influence on earth (in the event of the sun’s instantaneous disappearance) is something I never heard or thought about before, but it makes sense. It’s hard to visualise it though. Like the earth is a marble circling a drain after plug has been pulled and the water is all but gone. Then the minute it is gone, the marble just keeps going in a straight line 👀
That’s amazing, thank you! A ghostly remnant of gravity still exerting 8-ish minutes of influence on earth (in the event of the sun’s instantaneous disappearance) is something I never heard or thought about before, but it makes sense.
Also for us standing on the sun facing side of Earth when the magic wand was waved would still see the sun shining in the sky for 8 minutes because that light had already left the sun before it blinked out of existence. We on Earth would experience the loss of the Sun’s gravitational influence on the planet and the light of the sun at the same moment as both light and gravity travel at the speed of light.
I think it's easier if you imagine space/time like a flat plane that dips depending on how much mass the central object (like the sun for example) has. Earth circles around that dip much like your drain plug analogy. If the sun disappears, it still takes time for that dip to rise back up to a flat surface. That's the speed of gravity.
As soon as space/time begins to flatten beneath the earth, its momentum begins to turn into a straight line, rather than an orbit.
You are seeing the exhaust plume while it is still dense enough to reflect enough light from the sun.
There are several massive thermal layers in the atmosphere that effectively make isolation barriers at various heights. That is why the exhaust on the left appears unique in structure within a certain boundary. The upper layers of the atmosphere get really hot before getting really cold again. Like commercial jets fly in the cold part, but it gets hot, then cold above that. The rocket plume on the right is in that upper cold region; the outer most puffy/sparse/low Earth orbit region. You can tell because of how enormous the exhaust plume is expanding when there is very little atmospheric pressure to contain it.
There is very little atmosphere way up there and certainly not enough to produce Rayleigh scattering. If there was enough to produce Rayleigh scattering the exhaust plume would be hard to see with very little contrast against the background, but without, it makes a much higher contrast view against the mostly empty void of LEO space.
Exhaust products and a small amount of either O^2^ or unburnt. IIRC SpaceX is a fuel rich cycle, so mostly +unburned fuel.
Think of it kinda like you’re seeing an isolated atmosphere made by the rocket suspended in a place nearly without atmosphere. It is like a cloud of atmosphere in space where there is no atmosphere.
It’s mostly in the sun which is super hot without the filter of an atmosphere and how it buffers temperature. As soon is the particles are below the shadow of the Earth, they get super cold and likely freeze.
The rocket is clearly not at orbital velocity yet and that stuff is going backwards fast, so it will all deorbit fairly quickly.
You’re not seeing turbulent flow quite like what happens on the ground or what is seen in other parts of the exhaust plume because there is not very much pressure in the surrounding region to create the Eddy currents that make the mixing/chaotic flow patterns seen within another medium. I don’t think it is entirely linear flow, but it is much closer to linear flow than what happens in a thick atmosphere.
The problem would be that you would need a very heavy gas in that mixture. Which would soon unmix, with the heavy gas at the bottom and breathable gas at the top.
Also be careful with breathing even minute amounts of such heavy gasses, as they will accumulate at the lowest parts of the lungs.
I remember a TV show where they breathed such a heavy gas to show what it does to your voice (it transfomed it way down, just like helium transforms it up). They had to stay upside down after that for some time to get the stuff out again.
According to your link, this is actually used in big plants:
Vacuum distillation is often used in large industrial plants as an efficient way to remove salt from ocean water, in order to produce fresh water. This is known as desalination. The ocean water is placed under a vacuum to lower its boiling point and has a heat source applied, allowing the fresh water to boil off and be condensed.
Using bioelectric microcurrent waves to disturb the biological metabolic reaction and structure of bacteria that forms an impenetrable biofilm
Well, it certainly sounds like jargon designed to obfuscate the actual process. At a minimum they’re relying on scientific opacity to render a buyer “convinced because it sounds smart”.
I’m always skeptical of these things. Anything that can truly destroy the biological elements that make up plaque bacteria will also likely destroy the cells in your gums. So you’re left with either a very mild human-cells safe process that is so mild that it also does little to nothing to the other things, or you actually have a dangerous process that is also dangerous to your human cells. Like drinking bleach to cure COVID… I’d rather that, if they are doing anything at all here, it’s entirely placebo (beyond the usual brushing effects).
In the US PNW coast area Douglas Fir trees are harvested for lumber within about 30 years, plus or minus. Maybe the person you were talking to was considering the harvest of the tree to be the moment when the CO2 is "reclaimed"?
Wrt to when the tree pays off the carbon footprint generated by raising and planting the seedling, I guess it's less than three years.
Fun fact: Douglas Fir reach peak carbon fixation rate at about 120 years.
I highly question this. A Dougie at 30 is about a foot across. I just took 7 Dougie’s down on my lot, the largest was 24in at chest height. I can see Puget sound from my place. In fact, I actually counted the rings on one of them and it was 101 years old. Shit. Now I’m gonna go look and measure the 30. I dyed every fifth ring when I counted it initially.
K, so at 30y/o the only stump I left in the ground was only 8.5 inches across and 20in in diameter at 101, so that’s an easy 24in with the bark. The tree was 120ft tall when I felled it in July. A real shame too, I wanted to keep all of them but fire damage. The next day beetles had already hit all of them. I dropped the trees a week after the fire and debarked them to help protect the wood before i could mill them, and there were hundreds of beetle tracks under the burned bark. Pine beetles live under the bark, in the cambium, no bark=no beetle. But the California wood wasps showed up the day I dropped the bark. Those things are terrifying, jet black, 2.5 inches long with an inch long stinger on top of that, so about the width of your palm. Adult pine beetles are about 3inches long when they emerge too. Wicked little fuckers, the both of them
Awesome, so if I’m reading that right UV can contribute to growth, and IR doesn’t contribute much at all. The blue and red end of the visible spectrum encourages growth, however it can pretty much occur at any visible wavelength, just not as efficient as the bands listed on the image.
Blue and red are the biggest drivers for photosynthesis, but other wavelengths have effects on the plants as well. For example, far red light (infrared) has a huge influence on flowering and stem elongation in many plants. They really rely on light for a lot of cues for regulation.
That chart is a good starting point, but it doesn’t tell the whole story. It only shows the absorption spectrum for Chlorophyll A, which is a key pigment for photosynthesis in all plant species, but there is also Chlorophyll B, and there are numerous other so called accessory pigments (beta carotinoids are the most common examples), that can work in conjunction with chlorophyll in a photosystem to collect light of different wavelengths. Algae in particular show a greater diversity of accessory pigments. They have evolved use light at different depths below the water surface, where it reaches them with a different spectrum, because water itself absorbs part of it. Have a look at red algae and brown algae, for example.
So if you want to grow algae in a controlled environment, you should do some research about the particular absorption preferences of the species you’d like to grow.
What would be ideal IMO is a bug with a gut bacteria exclusive to that species alone that could eat plastics and digest them fully so microplastics aren’t an issue. Likely, a species for each type of problem plastic. A natural analogue would be termites, which can only digest wood because of such a relationship.
It would have to be an artificially engineered relationship, and an insect that’s not particularly proliferate. Preferably with a narrow set of habitat tolerances. That way they could be farmed, but be unlikely to get into the environment and become a nuisance by eating plastics we don’t want them to.
Black soldier flies are prolific and when proper conditions to reproduce are met, the females do not wander far from the place they are born and because of this are already used in organic waste disposal.
Using a complex organism to treate waste, even if only plastic, requires specialized infrastructure, designed to contain any event possible to pose a threat to the environment; this is not something we want or can do at home. Specialized infrastructure would make possible ideal conditions for the flies.
Black soldier flies also have the advantage that adults do not live for very long, do not feed, do not pose threat to human beings and the larvas die quickly if no food is available.
These flies also are vulnerable to cold and extreme heat conditions.
Most allergic reactions start with milder symptoms, and some get worse each time you’re exposed. You would probably notice (and hopefully see a doctor about) the burning/itchy/numb mouth and throat, and/or upset stomach, before it progressed to a lethal allergy
This is what I thought - I just wanted to make sure I hadn’t failed to consider something obvious. Am meeting up with some old friends who are science geeks next month and wanted to throw out the line “for all we know, the center of the galaxy exploded 25,999.9 years ago and we could all die tomorrow” and I didn’t want anyone coming back with “well actually…we would have detected that by now thanks to technology xyz that was in ivented in 20XX”.
I totally misread your post as you were meeting up with some old friends who are science geckos and I wanted the story behind all of that, but then I read it again and was disappointed in the lack of geckos.
If the black hole specifically disappeared, it would have no effect on us. The solar system would not even be launched on a 100 million year trajectory out of the galaxy, as galactic rotation is dependent on the masses of stellar and interstellar matter in the disk and dark matter in the halo. The supermassive galactic black holes, despite being supermassive, still only make up a tiny percentage of total galactic mass.
If you want to wow your friends, tell them about false vacuum decay. We could have bubbles of true vacuum expanding out in space from multiple directions towards us at lightspeed, and no way of knowing about them, stopping them, or outrunning them. Any point in space could nucleate a new true vacuum bubble at any time, just like a given uranium atom could decay now or in 5 billion years or never. Even spookier, by principle of quantum immortality, the Earth could have been engulfed by vacuum bubbles many times before, and we are just the one tiny sliver of probability space where by luck alone we survived long enough to talk about it here and now.
Thankfully false vacuum is just an idea and there is currently no evidence that it is real.
Many worlds is a fun idea, too. But also being regarded as not real for a while now. The cat in a poison box living or dying doesn’t mean it lives and dies.
I never heard about the false vacuum before, that’d be some good sci-fi
There isn’t a link in your post, but it looks like you’re referring to this preprint. The article has been published in a peer reviewed journal paywall warning.
This is a review article, so it isn’t proposing anything new and is instead giving a summary of the current state of the field. These sorts of articles are typically written by someone who is deeply familiar with the subject. They’re also super useful if you’re learning about a new area - think of them as a short, relatively up-to-date textbook.
I’m not sure how you’re interpreting this review as an alternative to the standard model of cosmology and the Big Bang. Everything is pretty standard quantum field theory. The only mention of the CMB is in regards to the possibility that gravitons in the early universe would leave detectable signatures (anisotropies and polarization). They aren’t proposing an alternative production mechanism for the CMB.
Haha it’s in the title: “Cosmological Particle Production: A Review”. Also the journal it was published in is for review articles: Reports on Progress in Physics. Mostly though the abstract promises to give a review of the subject.
Another indication is its lengthy (28 pages) with tons of citations throughout. If someone is doing new work, citations will mostly be in the introduction and discussion sections.
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