Spacescifi

Behind the ship? Where the photon rays are shooting? That will burn up the radiator fins. The math does not look good if you calculate the radiator fin size for a 1g photon rocket. It's extreme. Nevermind the weight, which would be massive. Which means the RCS will use large amounts of propellant unless you want to take days rotating the vessel. And photon rockets require working mass to get their power... antimatter. And the slower option? Have a nice voyage. You're leaving home as you know it forever. Wayyy too slow.

Hmmm... hard scifi? Photon rockets of 1g requires radiator fins several kilometers or much greater in length and width. How are going to shield those? When all factors are taken into account, hard scifi falls apart at tasks that more or less require making stuff up.

Congratulations! You have a fighting chance of surviving the Oort cloud! Where there is will... there is a REALLY hard way at times. I hardly need excuses, if I can't find a way out of a paper bag I find someone who can. If they tell me I will have do a bunch of things that will take more time than I want to take... then making it up is preferable. Time dilation leads to a very specific kind of story I cannot afford for the plot to work at all. Imagine Star Wars with time dilation... or Star Trek. Neither would be the same. Not that I am doing that. I understand... but part of the appeal is the thrtll of space travel. It's expensive IRL, but I can surely let the reader experience what it's like to float in weightlessness. That's my primary reason against AG fields. Adventures through writing. What if questions. Ironically when creating aliens physics gives a lot more freedom and leeway than making their spaceships. So honestly, I have to make up more with the spaceships than the aliens themselves LOL.

Honestly... I had to sift through google images to get one that was appropriate. This one appears to be a modded look that does not naturally occur ingame. People mod a lot.

Not to the same extent... humans have put it to the test and died or nearly died. Like no one in his right mind will kill a bird, eat some of it, bury it in dirt, and eat the rest a few days later (barring the gross parts). One thing I do like about cats is they are are not keen on eating poo of other species or each other. In fact, if they sniff the bile sac of animal they will rip that out and put it aside, they won't eat it. Cats have 'street smarts'. Like they know what and what not to eat when it comes to the natural world. It is human food that tricks and confuses them at times.

Sure... and actually... yeah, cats do have really strong digestion. Sand cats just bury whatever they cannot eat in the sand and come back to it later, so I suppose that could work for my cat people, no brine or human level salt tolerance required as kerbaloid and ARS implied. Sandcats get much of their water from the blood in the meat they eat (gross), but will happily drink water or milk if available. So I will do that, the non-human features are where the fun is, whereas the human side of them allows them more depth and interaction than would be possible otherwise.

I have. Humanoid cats as I envision them take only specific cat traits I want them to have. Sure the sand cat can make it, but a humanoid cat is much larger, and will need to work a human style work shift rather than sleep much of the day like the sand cat does. Otherwise culture and tech will take too long to develop. More active life equals more water and food intake required. I don't do a 1.1 corrolation from animal to human, since nor all abilities translate as useful. Like cat eyes... not so useful for a humanoid cat, better to keep the human ones. At most you could give them tapetus lucidum that allows better night vision at the expense of reduced distance vision in daylight making distances of 20 feet blurry. Think more dr moreau... I know cats cannot tolerate much salt... but these are not pure cats. These are humanoids with cat traits and features. So they actually could tolerate a human salt intake, yet they would need a high water intake to balance it out. While they do have digestive systems able to digest stuff that would challenge or harm a normal human, they also have limits to that. I think some sort of food preservation would be in order, since eating rotten meat like vultures is not something cats are keen on... or are they?

No... I am saying with human intelligence and the feast or famine routine cats do, cat humanoid folk would spend days without eating working out plans on how to get meat more efficiently the next time. They would sooner or later work out that fishing and storing it away in brine is safer than chasing down terrestrial prey whenever they become hungry. Being carnivores, they could likely eat fish fresh as well as cooked. Thus civilization growing from and around water sources. Historically human civilization grew around water sources, but for far many more reasons than the carnivore catfolk... who absolutely need it. Carnivores have less options, but they can still prosper and grow within them. I don't see them dwelling in deserts at all.. until their technology catches up. Strangely enough they could do fine in arctic conditions so long there is prey, they would be like Eskimos.

Not sure he did... science is an ongoing thing, and scifi will always need to be updated with new knowledge so long humans are not all knowing... which will likely always be. If google is correct in what I read, the Oort cloud is a SPHERE. Flying above the solar disc won't help, as even if you flew above the solar plane you would hit the cloud eventually. It's the cloud. Absent hyperspace, wormholes or some super warp drive... deal with it. The Oort cloud. Or don't. Which is what we have done so far. Scifi either should... or find a way to circumvent it I believe. Rather than ignore it as if it is not out there.

Really this thread demonstrates how difficult space travel is... even with impossible tech it is still easy to die. So it actually encourages making stuff up... not arbitrary... necessary if you want a specific space opera plot. What IS NOT NECESSARY: Artificial field gravity. Other realistic easier ways to do it, and while 1g constant acceleration is currently a dream, it is at least a concept readers can understand as opposed to a totally arbritary 1g field we make up with arbritray limits imposed. Plasma weapons: We know in previous thread why. Basically, where necessary make stuff up, where reality does a good job... KEEP IT. I actually find the idea of death by space rock amusing. Could have been very anticlimatic: "We are doomed! The enemy flagship outclasses us in every way!" "We were. A space rock hit them along the way. What happens to 9000 ton space battleship when it hits a 500 ton space rock while traveling at 99% lightspeed." "Boooom!" *Fist bump with an explosion gesture afterward*

Low densiity just means the rocks are spread out... it does not mean some of the rocks are not big like this: A cursory google search of oort cloud object size supposes this: The outer Oort cloud may have trillions of objects larger than 1 km (0.62 mi), and billions with absolute magnitudes brighter than 11 (corresponding to approximately 20-kilometre (12 mi) diameter), with neighboring objects tens of millions of kilometres apart. Wikipedia › wiki › Oort_cloud Oort cloud - Wikipedia So maybe you won't hit it, maybe you wiil. It may be closer to a 50/50 chance than it is 99% certainty you will get hit by a massive object. But we simply do not know. Scifi will attempt to 'splain' things meantime lol.

If you want to avoid flying through lightyears of rocks or come back home without everything changing you do. No one has even addressed how to dodge stuff at 99% lightspeed. I think even the so-called hard scifi ignores that, pretending that it is a sure thing the vessel will fly through oort clouds without hitting any of them or having to deflect or shoot them. Like, one would either need scifi shield generators or weapons stashed right next to the engines to fire backwards as they retroburn! Well not all scifi ignore travel collisions.... the movie Passengers showed the interstellar space vessel hit a rock along the way, though it looked as if they had a scifi shield, otherwise one hit should have nuked them. The time dilation makes it worse, as it gives the ship even less time to make course corrections.

No intention to go full relativistic. Not once I learned that solar systems carry their own WHIPPLE SHIELDS to kill incoming relativistic masses flying at ludicrous speeds. 2 LY of oort cloud dodging or blasting is hardly a nontrivial concern LOL. Make that 4 yrs or more if you count the next system over. I have a sneaking suspicion that most solar systems have oort clouds, some with more rocks, some with less.

So much for that idea then LOL! Too long for plot. No problem I can use older ideas. Yet it is fascinating how hard space travel is even with scifi abilities thst are impossible. Long story short... we NEED FTL warp or a hyperdrive or wormhole analog to ever travel interstellar distances safely and efficiently. Since if you tried that with constant acceleration... impossible as such currently is... you risk dying here at the oort cloud or in the next solar system's version over. Wow.

The oort cloud is a region where the sun's gravity is more or less null and void. The oort cloud is about 2 LY accross if I read correctly. It would take the Voyager probe 300 years of inertia driftng just to reach the edge of the oort cloud, but by then it's instruments will be long dead anyway. It is the edge of the solar system if you consider where the sun's influence ends. So if you had a scifi 1g constant acceleration propellantless drive how long would it take to reach the oort cloud? From low Earth orbit? My guess? Months. Or over a month at the fastest. Reason? In scifi it could be that interstellar wormholes are only formed where star gravity is virtually nonexistent, requiring travel to the edge of solar systems. Why go through the trouble of such long travel times? Makes near lightspeed RKV attacks via a wormhole at the edge of the solar system easier to guard against. Plus if it hits one of those ice rocks it's probably mission killed anyway. It also demonstrates that leaving the solar system for another at 99% lightspeed is not easy even if you can go that fast. It is rather hard to dodge rocks in your path at that speed, and we are talking TWO light years worth of rocks scattered about. Any one of which could ruin your lovely trip. Like you either need an UBER deflector shield to protect a vessel from asteroids or need to go in guns blazing with several antimatter particle beams to blast the rocks before they reach you. As per the usual... offense is easier to do than defense... it would take a truly scifi deflector field to deflect rocks when you're going at 99% lightspeed.

Is building a magnetic rail 30 kilometers high practical? I mean... it might be plausible, but such a feat limits how heavy you can launch.... leading to time consuming launch a piece, rendezvous in orbit assembly.

Haha... pastoralist cat-girls... funny imagery. It is the inverse actually I am thinking. Cat humanoids preferring to live NEAR beaches and rivers where access to meat is easy. Any alien bears trying to get fish in the river are likely going to get speared to death sooner or later as a meat source. So they would start their civilization near water sources, and only as food preservation technology advances will they progress to animal husbandry. Besides... although my cat humanoids will have human intellect, they will be known by other races mostly for the three P's. Paranoia: Because real cats definitely act that way. Persistence: They are this way too. Predation: Hardwired carnivourous need to hunt for meat, acomplished through hunting when no tech options are available.

I barely even know what that is... but I get you.

We discussed to death how lame plasma weapons are... but I digress. Assuming that vessel is using a high powered particle beam instead it would require an INCREDIBLE amount of energy to cut through all those layers of atmosphere. Since they appear to be flying extremely low orbit. And a laser would be much the same, just likely weaker overall. It would be arguably cheaper and more efficient to just fire some railgun or coilgun rounds. Way more damage, less energy to fire and or produce I might add.

What other options? Generally... keeping the amount of antimatter low is a good thing when launching from a planet or even landing due to safety concerns. Also... how would the exhaust plume look? My instincts say steam... lots of it. But I don't know why but having flamey plumes come from water reacting with AM seems odd. Yet for all I know it would probably be a flamey bluish plume with a lot of steam exhaust. Am I even close?

Turns out I was wrong about carnivourous humanoid cat-folk being unable to develop technologically as a scifi civilization. Provided human intellect is at work. In an earlier post I said they would not due to a lack of food resources, and that animal husbandry would be difficult if not impossible due to a predatory drive as strong as is the human desire to to mate. Upon further research I learned they have options that could easily lead to sustainable animal husbandry. 1. Fishing. Assuming rivers and oceans teeming with fish, all they need is to bring in a big, big catch and find a way to store the meat... or not. The GREAT thing about being a carnivore is you don't have to eat everyday, but you feast like a king or queen and share with family and friends when you do. 2. Don't know if making dried fish jerky is practical, but I am sure in the early era they will try this. 3. Advanced hunting techniques will abound. Given their innate need for meat, they will be more adept at hunting animals then your average human. So much so that in general, every animal they ever see they will be thinking... "I wonder what they are like to hunt?" Traps for prey will abound, and being humanoid apex predators, they will feel free to hunt predator animals for meat too. 4. Expert fishing would lead to a ready supply of meat, which could allow them the time to develop cattle herding. Eating the cattle would thin it out fast though, so I suspect that cattle herds will be smaller than human ones usually are, reserved for celebratory or special occasion meat. That said, anyone with a lot of ready meat supply would be wealthy early on. 5. With technological innovations like refrigeration and gas ovens, suddenly average citizens can eat without even hunting, leading tech innovations to explode. Since carnivores can spend days without eating doing other pursuits. 6. Thus they could develop space travel. All they need is a WHOLE lot of frozen meat to dethaw and water supply. 7. Their predatory desire would remain though, so they would need to pack meat jerky on them to snack, on, since if they run out of meat on a spacecraft, the slaves or least valuable crew members will start to look like a good substitute.

Interesting. So you are saying that trying to induce antimatter triggered nuclear reaction is just an expensive way to kill the self and everything around three kilometers out and maybe a bit further? It's a bomb? No record os fission reactions? Too bad...I had hoped that we could make mini reactors ALA Ironman. Jury of experiments is still out though... since absent data to disprove it we can still experiment. And modernt tech may yield somewhat better results? Or not?

Cryo-sleep is pure fiction. So are sustained pure fusion reaction right now (burns down the container it's in if it touches it, and magnetic fields can't keep it totally contained). The ideas presented here only work when the assumptions are true, but past research has shown otherwise. Yes you can freeze a sleeping human body body. Know what happens when you unfreeze them? They. Are. Dead. Frogs survive what appears to be a frozen state, thaw them out and they are fine. Frogs also have a different biological system with a kind of antifreeze in their blood that prevents the blood from freezing over. We do not have that. Frogs are also cold blooded. Your ideas here could certainly work in and even seem inspired by scifi, but they are not practical for real life applications. Bussard ramscoops are great.... when there is enough hydrogen to scoop. Interstellar space is about the worst place to get it. You want to be near a star, not far away for a bussard scoop to be most effective. So if you want to write SF go right ahead, many either won't care or know of it's inaccuracies. But as per the usual, scifi tropes hardly ever work the way they in do in fiction as they would in reality. Also... why are you so keen on sending human bodies to another solar system? Before we have the requisite iterative abilities to make the most of the situation? I assure you... we don't.... yet. The time will come. If you want it sooner, write scifi.

In scifi there is.... I don't really mind if IRL it is rare because it is purposeful. We explore the hypothetical what if's in scifi, not what is.

Depends on how determined a civilization is about colonization. Colonization involves.... conquest. There, I said it. Does not matter who or what already lives there, they must be assimilated to service the colony... or wiped off the face of the planet if they cannot be of any service... which is also highly unlikely. More likely greed would cause that, not practical concerns.