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Joined 2 years ago
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Cake day: June 12th, 2023

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  • What did the doctor say? You may have a fungal infection, where the welts and itch aren’t caused by dryness or the scratching, but by the fungus. It’s actually really common and can be extremely annoying if left untreated. Some miconazole nitrate cream can really help out with this, just a few weeks of applying twice a day and it’ll clear up.

    But never take medical advice from the internet, go see a doctor and ask them what to do.



  • Yes

    As long as the object doesn’t reach escape velocity, it’s in orbit and thus bound by the primary object. Now this orbit can by very weird and huge, but it’s still a loop. Only above escape velocity does the loop “break” and leaving the object without a guaranteed return is possible.

    So in theory if an object is in orbit and the boost is sufficient, it can just leave. However even then it is subject to the gravity fields and will make an arc instead of just a straight line. So “point and shoot” is never really an option. But often in movies a small spacecraft is seen making a small maneuver and somehow being seen as lost to space. That will for certain not be the case, a small boost just gives you a different orbit, but an orbit still.

    For example the movie Life (2017) comes to mind. Spoiler alert. In the end they decide to use an escape pod to launch into “deep space” with the alien. The escape pod just points up and fires the rocket for a short while and now is lost to deep space forever. This is total nonsense. The reason escape pods can work with very little fuel is they often have just enough oompf (or delta-V if you want to be technical) to put the pod into a slightly lower orbit. This lower orbit means more drag from the atmosphere which slows it down further, lowering the orbit again etc. until the thing is slowed enough it can totally re-enter and land. It isn’t like an escape pod pointed down goes to Earth and pointed up goes into outer space. The pod actually fires in the direction of the orbit, so horizontally, in order to slow it down.

    Orbital mechanics get really weird really fast. For example slowing down can cause the orbit to become higher before it goes lower. And putting in energy sideways can alter the angle of the orbit just like those spinning flywheel desk toys. Playing around with orbits in Kerbal Space Program can give a better understanding and can even make the concept of delta-V very easy to understand. KSP players would be unable to watch the movie Gravity (2013) for example without screaming at the screen: “THIS IS NOT HOW ANY OF THIS WORKS”.

    It’s hard to figure out, that’s why we refer to hard things as “rocket science”. It’s not just the complexity of the rocket as a machine and engineering challenge. But also figuring out stuff like orbits, taking into account the different gravity fields of objects that are of note. Doing things like gravity assists or Hohmann transfer orbit, taking into account the influence the extremely thin atmosphere has. And remembering everything moves, so shoot for where the target is going to be, not where it is now.


  • There is a few different concepts here in conflict, which is why the question is hard to answer.

    What do we mean when we say space? Usually we mean above the Kármán line, or above 100km. At that point you are above almost all of the atmosphere, so we consider that space. The atmosphere does actually extend quite a bit above that, but at that point it’s so thin we consider it to be space.

    However as we know, the Earth has a bunch of gravity from its mass. So when you get up to 100km you just fall back down. Space isn’t free of gravity, the gravity of the Earth extends basically for ever. It’s influence does get less (thanks to Newton we know by how much), but considering the Earth is thousands of km wide when we get up to 100km we are basically still on the ground as far as gravity is concerned.

    So why do we see astronauts fly around? They are weightless, so there is no gravity right? This is something popular media gets wrong a whole bunch, it’s not like there is some magically line called space and beyond there you are weightless. Those astronauts are actually in orbit, that’s why they don’t experience gravity from the Earth. To understand orbits, imagine we fire a big ass cannon. The ball flies through the air in an arc and lands on the ground. How far away it lands, depends on how fast we shot the ball. The faster it went out of the cannon, the further it flies. Now imagine we shoot the ball over the horizon, so it lands so far away we can’t even see it anymore. It still lands right? Yes, but only up to a point. It turns out if you shoot the ball fast enough, the arc just continues falling beyond the horizon until it loops around the Earth. As it is falling, it doesn’t experience gravity except for the arc it follows.

    Usually when we put stuff into space, we mean put it in orbit and especially something called Low Earth Orbit . That means it needs to have a speed just like the cannon ball, to keep falling indefinitely. The speed we need is dependent on how large the arc we want to have, or in other words how high the orbit is above the Earth. For context, if we want to fly in orbit in space so at an altitude of 100km, we would need to go almost 28254 km/h. Imagine driving that fast on the highway, it’s crazy fast.

    That’s why we use rockets, it’s not as much about going up, it’s more about going really fast. So a rocket takes off and goes vertical for the first bit, this is to get to a thinner part of the atmosphere to reduce drag. Then it does something called the pitch over maneuver, usually in the form of a gravity turn. This is to go mostly horizontal and get that speed up. At the speeds rockets are going, they get to the 100km altitude in no time. So they pitch over as to not overshoot and use all their energy to go as fast as they can horizontally and thus into orbit. Then you get into the realm of orbital mechanics, which popular media also gets wrong a whole bunch. You can’t just point you spacecraft into space, give it a boost and be flying off into the void forever. If you want to learn more I would recommend playing Kerbal Space Program, to get a feel for how orbits work.

    But say we are totally done with Earth and just want to leave it all behind, go into Deep Space. How would we do that? For that we need even more speed, something called escape velocity. If we get to that speed (40270 km/h), we can leave the Earth and go wherever we want, right? No not just yet, we might have left Earth behind, but we are still in orbit around the Sun. So we are still following orbital mechanics, only the Sun is the primary body we have to account for instead of the Earth. We can use orbital mechanics to fly around the solar system.

    If we want to leave the solar system, we would need to go even faster. But the issue is there is nothing out there. To get anywhere interesting, we would need to travel close to the speed of light for years. Even our fastest spacecraft are standing still compared to the speed of light, so leaving the solar system isn’t very useful right now. But we do have the Voyager space probes which kinda sorta left the solar system and we got some interesting data from them, which is cool!


  • I have both kinds and I don’t really care. I just buy the pants because I like how they look, don’t even check what kind of fly they have. I have the ones with a regular zipper and 1 button, zipper with 2 buttons, no zipper just buttons, a little hook thingy button and fly combination. There are more important aspects of pants for me, like the fit, feeling, price and how they look.



  • My personal advice: Take notes.

    Just write everything down. I recommend an actual physical little paper notebook and a pencil. If you think: “Oh I must remember that” or “I’m almost out of …, I must buy more”, write it down.

    Now don’t go writing down stuff like fun facts or YouTube videos you want to watch. Make it all practical stuff, stuff you need to do or is important in your life. It’s your brothers birthday next week, write down the date and what you need to do to prepare. Your stomach hurt and you think you ate something that didn’t agree with you, keep a log of what you ate and how your stomach felt. That way you can identify allergies or things you can’t eat (anymore). Having trouble remembering names? Write down after you met someone: “Today I met Steve, Steve is in charge of accounting at Megacorp.” Measured the room you want to put new flooring in? Make a little sketch and put the measurements in.

    Writing stuff down physically forces your mind to pay attention and remember it later in a structured way. It also feels really good to physically tick off a task or cross it off. It can be a bit hard to keep up with and not go the other way and put so much into it, it doesn’t help anymore. But it can help a lot, especially if you are the kind of person that thinks 8 times a day to put out the garbage, only to wake up the next morning and you’ve forgotten to actually do the thing.



  • Not true actually, there are many hotels with excellent food. There is a hotel not far from me where a lot of people go to their restaurant even if they aren’t staying at the hotel, it’s just a really good restaurant in it’s own right.

    I’ve also been on holiday where we had excellent breakfast options in the hotel, even the ones included were very good. You just need to check for those when selecting a hotel. I’ve definitely had worse meal in some restaurants than I’ve had in some hotels, there’s plenty of overlap there.



  • I agree, but with a security device this is probably not the best idea. Any kinds of tampering physically would most likely trigger the alarm, sometimes in a way that can only be fixed by calling a tech. Software tampering if you do get it connected would probably have the same result.

    We’ve had this at work once, they were doing some remodeling and somebody accidentally hit a sensor with a large machine. The sensor was destroyed and the alarm went off (even though it wasn’t even “on” at the time, as it was in the middle of a day). No codes on the panel could turn off the alarm, not even our super duper override code. We called support, they gave us a temporary override code and even that one didn’t work. They said with physical tampering a tech must come by on location to tell the system all is OK. We had to work for 4 hours that day with the most annoying alarm sounds in the background. The worker that hit the sensor was very embarrassed about it.


  • Thorry84@feddit.nltoSelfhosted@lemmy.worldMy First Homelab
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    1 month ago

    Just so you know, operating spinning drives this way is a bad idea. If the platters are spinning and the drive tips over, the rotation of the drives resists the movement. This gyroscopic force is enough for the platters to touch the heads which are flying a tiny distance above the platter. Obviously this is a bad thing and will damage the drives.

    A quick fix is to just lay them flat or fix both of them together so they have a more stable base to stand on. Putting it in an enclosure is even better.




  • With a custom made staircase? Why would the holes already be drilled? I’m not sure that blue color is the final color, or just a primer to prevent rust.

    With the staircase I had it was simply 4 holes drilled in each stair and a short but fat screw driven through. This lead to bowing in the middle over time which made the stairs creak. So when I refurbished it, I drilled extra holes in each stair. As well as a thin strip of rubber over the top of the metal. Drilling in a relatively thin flat piece of steel like that is pretty easy. It wasn’t particularly hard as it was designed to flex with use instead of being super hard and being subject to metal fatigue. The holes weren’t that big, iirc they were 8mm.

    I drilled the holes by hand and it was fine. Sure it’s a pain in the butt because there were so many stairs. But that was kinda par for the course in a project like that, especially since every stair was unique with it not being a perfect circle. But for people who do projects like this for a living, they have one of those fancy magnetic base drills. Those make easy work of something like this.

    The wood would most likely not be fixed to the wall and be designed with a small gap to allowing movement. Wood tends to move around a lot, so you want to have it free to move where possible. Just bolted to the metal would be just fine.



  • Thorry84@feddit.nltoFunny@sh.itjust.worksWhy? A e s t h e t i c
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    2 months ago

    The lights are embedded in the wall and the stairs are fixed to the wall. So they probably wanted to finish out the wall before they put in the stairs. The wood of the stairs would also need to be fitted to the wall exactly, so it makes some kind of sense to finish the wall first. I would have opted for little nooks for the stairs to fit in, but there were probably reasons that didn’t make sense in that situation.


  • Thorry84@feddit.nltoFunny@sh.itjust.worksWhy? A e s t h e t i c
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    2 months ago

    This has been reposted so many times. It’s obviously a work in progress, with the wood from the stairs missing. The floor doesn’t look finished as well.

    I used to live in a home with a spiral staircase very similar in construction to the stairs in the picture. Once I removed all the wood in order to clean, fix and re-finish the wood. With the wood removed it was in fact a death trap like shown in the picture. I replaced the wood with temporary OSB cut to the right size, which actually looked kinda cool.


  • Yes the myth that irradiating something makes it radioactive is a very persistent one.

    The reason radioactive material is so dangerous, is because it has the tendency to spread around. Not the radiation, but the material itself. Then people get exposed to that radiation and hurt themselves. There is a particularly tragic accident that happened in 1987 in Brazil where thousands of people got exposed to a stolen radioactive material. Especially when the material sheds dust it’s very dangerous because it can then easily be ingested and even low levels of radiation which normally wouldn’t penetrate the skin can cause issues inside the body.

    https://en.wikipedia.org/wiki/Goiânia_accident

    Another reason the myth persists is because high enough levels of radiation can cause other materials to become radioactive. However on Earth this is only the case inside of fission and fusion nuclear reactors. And the source of a lot of the radioactive waste. But outside of that, nothing on Earth will make another thing become radioactive.

    I know a lot of the food used in the military is normally irradiated. This allows for a long shelf life, which is particularly useful if you are killing kids spreading freedom on the other side of the world.


  • The name for the insect probably originated in the Caribbean. Then brought over by the Portuguese and transferred to Spanish. The English got it from the Spanish, where other languages like French and Dutch got it from the Portuguese.

    In English it went from the Spanish cacarucha to the English cacarootch. Which later changed to cockroche and eventually became cockroach.

    The original Caribbean word was most likely kakalaka. This went to cacalacca in early Portuguese and then into the Spanish cacarucha. Interesting enough the newer Portuguese word of caroucha was based on the Spanish word. So the word went from Portuguese to Spanish and back again.

    People always forget languages are a living thing and words for a lot of things were very different hundreds of years ago.