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Achondroplastic dwarves are resistant to osteosarcoma. Ionizing radiation is a problem for space travelers.* It is very difficult to block energetic particles and as the cumulative dose rises, the incidence of cancer rises with it. The most common radiation-induced cancer is sarcoma, and of these the most common is osteosarcoma.* In the recent past of ...


133

Nope, we don't even use them today. Reverse thrusters are completely unrequired. Just flip the ship and use the normal thrusters. All the ship needs is: A means to rotate the ship. Normal main engines. Once rotated so that the main engines are pointing in the way the ship is traveling, just ignite those engines. Take a look at a SpaceX booster, the ones ...


125

Edit: The OP updated in a comment that communication is possible through the portal. My answer assumed that you had to figure out where you were from the other side, using only the information you brought with you. If you can do observations from both sides of the portal, then there is a way to find out where the other side is, so long as the event ...


123

Not sure quite what definition you want to give of "being a mercenary", but I spent a few years as a contractor in Africa, Asia and the Middle East after leaving the Army, so I can tell you why I spent a bit of time wandering around the smellier parts of the world between contracts. Connections You get hired and find contracts by making sure people know ...


123

A quick web search for "CLI vs. GUI" (Command Line Interface vs. Graphical User Interface) shows that many developers hold the following1: CLI is faster for an experienced user It is much faster to type than to navigate layered menus with a mouse. You can type with both hands, and it's easy to type blindly - so you don't have to keep your eyes on the ...


120

But in most stories, FTL doesn't actually follow Newton's 1st law; everybody knows that once your hyperdrive fails, you're dead in the water. Otherwise, the Enterprise could hit warp 9.9 and easily coast across the galaxy. And that actually makes sense in the warp-style of FTL: FTL travel is only possible within the field generated by a functioning FTL ...


118

Someone detected an asteroid There are lots of small asteroids. Even in 2100, when the solar system is well mapped, carbonaceous asteroids with low albedo will be very hard to detect passively. Further, radar is relatively ineffective for scanning the vast distances between Earth and Mars. A few hours before scheduled departure, a freighter coasting to Mars ...


112

They won't be crushed. In fact, they will feel less than Earth gravity, so they will need exercise to preserve their bones and muscles' integrity. 0.2c equals 59,958,491.6 meters per second. Two years have exactly 63,115,200 seconds. What this means is that if they were to accelerate at 1m/s2, which is pretty close to 0.1g, they would be going faster than 0....


99

In this reality, it would be impossible to successfully fake a moon landing at anytime. The moon landings happened. They were real with real competitors watching every move. A little back history will explain my point of why they could never be faked. As you may remember, the United States and the Soviet Union were in a space race to see who could make the ...


98

For the same reason some do in real life. Ship (or landing pod) landing isn't perfect so when they arrive back on earth the astronauts need to defend themselves against hostile animals or scavengers.


96

Put the food into cryosleep as well. If the people don't degrade, neither will the food.


96

These Torch ships have both the speed and acceleration to make a round trip from Mars to Earth in a week Average distance between Earth and Mars is 1.5AU, or 224,396,806,000 meters. Half a week is 3.5 days, or 302,400 seconds. Each leg of the trip is half spent accelerating and half decelerating, so we can calculate how fast we need to accelerate to do half ...


94

The crews have evolved on worlds with orientation, so their psychology and conventions reflect the reality that they are planetary creatures. Orson Scott Card captured the importance of orientation to human psychology very well with his "The enemy's gate is down" line in Ender's Game. Changing the perception of orientation changed the psychology of the ...


91

To make sure no space flight, just make the planet a little heavier. Based on chemical rockets, the cost to LEO is pretty terrible. If you increased the planet mass by a relatively small percentage, creating a chemical 3 stage rocket to deliver a payload (not payroll) becomes prohibitive or even just impossible. 25% more mass for the earth should do it. ...


86

As you said, any FTL drive is implicitly a time machine. Let’s review the reasons why. As a prerequisite you need to understand spacetime and the ideas of space-like and time-like intervals. first you need… We will make use of space—time diagrams which show that events (points in spacetime) have different x and t values depending on your reference frame. I ...


84

A pulsed fission engine like project Orion would have been able to move a 10 million ton ship into earth orbit. The downside is that they were achieving the propulsion with nuclear detonations. They would launch the atomic-bombs out of the back and detonate them a good distance away with a giant hemispherical "pusher-plate" which was basically a giant shock ...


83

Yes! And I shall do it by totally violating the low-tech spirit of your question! The biggest part of the challenge is your desire to go to Mars. Mars is a helluva long way away. If you were going to the moon from Earth, then I'm pretty certain you'd be fine. But a trip that far, with this kind of challenge? Doesn't appeal! Here's the key thing: no ...


80

You need more than dead. You need dead and weird. Interstellar spaces are huge. Ships need to be able to traverse these distances. The fact that there are clumps of matter - "dead worlds" - in between that are not useful to these ships should make no difference. It is like the fact that there are some empty office buildings on my route home. Who cares?...


79

I have a few ideas: Good ol Speed limits Look this a bit lower tech than your probably aiming for, but with an average distance between galaxies of about 10 million light years, and an average distance between stars of about 5 light years. Just pick a max speed that means they'll die and turn to dust before arriving in the next galaxy. If you can do 100ly / ...


78

The simplest way is probably to leave them with a shortage of unobtainium. A substance named for obvious reasons, that happens to be required for the production of FTL drives. Perhaps the limited quantity they had in their existing drive was destroyed (causing the accident) or dispersed in the accident. Either way, they're now limited to space habitats and ...


77

1. Space is mostly empty If you pull the trigger on this, you're ruining someone's day, somewhere and sometime Well, not necessarily. There's so much empty space between anything interesting in the universe, that it's very likely that those "shots from a cosmic shotgun" will just keep traveling through the cosmic void, never even approaching ...


77

Nope! (but you can still make this story work!) So the short answer is no - the power source would run out the physical hardware of the computer, thrusters, etc. would degrade high energy particles and high-speed dust collisions would slowly convert the spacecraft into a ball of metal and rock 50 years is probably about the limit of what is achievable ...


77

A few options ordered from "difficult but can be done at any time" to "easy, but requires an opportunity". Measure the gravitational lensing effect of the ship Every mass in the universe bends the space around it. This can be observed because stars behind the object appear displaced. This is how current day astronomers estimate the masses of astronomic ...


77

A simple humanitarian reason. If the problem is normal-serious, the troubleshooter can fix it, eventually awaking specific other persons. This individual is highly trained, augmented, decked out in Freeman class hazardous environment gear and given administrative privileges for every part of the ship. If it's so beyond-serious that not even the ...


75

I think one cannot use distant stars as reference points since we only know stars by their geocentric coordinates. We are smarter than that. The Pioneer golden plaques, besides having porn, also had this: With this you can locate the sun, by figuring out where the signals of 14 pulsars meet in a specific way. If you can track objects of interest, you can ...


74

A few little lies never hurt anyone, right? The problem of love and marriage falls into a major problem (DNA variety) and a bunch of minor problems (not so many fish in the sea). Surprisingly, the Major problem is far easier to fix than the minor, and it actually fixes a lot of the minor problems in the process. Gene Banks The main reason why love and ...


73

You're going to need to handwave this universe something awful Gravity is what keeps planets together. It's also what created them in the first place. Planets and stars form by pulling together all that breatheable gas. Solar systems can be thought of as cosmic vacuum cleaners. The star and the planets keep pretty much all the light-weight stuff "swept ...


72

I have painstakingly assembled a highly realistic relativistic raytracing 3d renderer and plausible geometry and position for nearby stars. Here's a render of the view to starboard: I'm sure you can appreciate the thousands of hours of compute time that went into this. Less facetious answer: Leaving aside the issues of whether there's any time for your ...


71

This is a simple solution rooted simply in the fact that Space is really, really big. In fact, have two solutions... If you are hungry but not starving, you have been unconscious for a day or so, at most. Certainly less than 3-4 days, or you would have died of dehydration. Unless the asteroid propelled you to super-luminal speeds or punted you into a ...


69

You Do Not Instead, the optimum response is to accelerate an unmanned ship from Earth (or LEO) such that at some point it matches the speed of the oncoming returnees, offload, turn the rescue ship around. Why unmanned? Because g. You can accelerate faster without fleshy squishy things on board, so intersect maybe even inside Sol proper, which means our ...


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