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I feel like something similar to this is announced every year, and nothing ever comes of it.
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Interestingly, while on earth 50 years will have elapsed, because of time dilation on the ship only about 40 years will have elapsed. It will get exponentially closer to 0 elapsed time as the speed approaches c. At 90% c only about 20 years will have elapsed [1]. Equivalently, as the travelers approach c, the distance to the destination will appear shorter. [1] disclaimer: I didn't do the math, i just googled the tab…
The math is actually quite simple to do yourself, your dilation factor is just 1 / sqrt(1-x^2), where x is a percentage of c from 0 to 1. So at 0c, your factor is 1 (obviously), at .5c it's 1.15, and at .9c it's 2.294. Divide the elapsed time in the stationary reference frame by the dilation factor and you get values that roughly agree with yours.
Ok, let's assume we find a warm, watery planet like Earth's within ~20 light years, and we figure out a way to travel >= 50% the speed of light, making it somewhat reasonable to get there. If the planet's gravity is greater than 10% different from Earth's, or its Day/Night cycle is much different from Earth's, wouldn't it still be a nightmare to live on. Anatomically modern humans have lived on Earth for 200,000 year…
People will get more sick, they will need more attention. But that doesn't mean that it is not possible.
Umeå is a Swedish city with a population of over 120,000. January has 33 hours of sun, while June has 286. That's fairly different from your usual place to live. But the city is a completely normal city. You need to go to more extreme situations to get a city that needs extreme changes.
So yes, there are challenges. People living in zero gravity has a lot of health problems, for example. But the most similar the planet the fewer problems there are. And it is cheaper and easier to move there.
Ok, let's assume we find a warm, watery planet like Earth's within ~20 light years, and we figure out a way to travel >= 50% the speed of light, making it somewhat reasonable to get there. If the planet's gravity is greater than 10% different from Earth's, or its Day/Night cycle is much different from Earth's, wouldn't it still be a nightmare to live on. Anatomically modern humans have lived on Earth for 200,000 year…
I'm going to show my nerd colors here but having a thought like this has almost ruined Star Trek for me. For me I often think about atmospheric pressure. There's no way that beings from so many different planets could exist on a single star ship set at 1 Earth atmosphere. Maybe someone knowledgeable in this space can tell me, but is a planet's atmospheric pressure reliably proportional to its mass?
Ok, let's assume we find a warm, watery planet like Earth's within ~20 light years, and we figure out a way to travel >= 50% the speed of light, making it somewhat reasonable to get there. If the planet's gravity is greater than 10% different from Earth's, or its Day/Night cycle is much different from Earth's, wouldn't it still be a nightmare to live on. Anatomically modern humans have lived on Earth for 200,000 year…
Even at 50% the speed of light, adding in a fudge factor for acceleration/deceleration, you're still talking about a trip time of 50 yrs. Even if you go all Neon Genesis and send 15 year olds on the journey, they'll be at retirement age by the time they arrive. In other words, you'd almost definitely have to send a generation ship. Which means you'd have to have already figured things like artificial gravity, giving…
Some kind of sleep hibernation tech, might make it possible to kind of stop or dramatically slow down aging.
Ok, let's assume we find a warm, watery planet like Earth's within ~20 light years, and we figure out a way to travel >= 50% the speed of light, making it somewhat reasonable to get there. If the planet's gravity is greater than 10% different from Earth's, or its Day/Night cycle is much different from Earth's, wouldn't it still be a nightmare to live on. Anatomically modern humans have lived on Earth for 200,000 year…
I'm going to show my nerd colors here but having a thought like this has almost ruined Star Trek for me. For me I often think about atmospheric pressure. There's no way that beings from so many different planets could exist on a single star ship set at 1 Earth atmosphere. Maybe someone knowledgeable in this space can tell me, but is a planet's atmospheric pressure reliably proportional to its mass?
One common solution in SF novels is for aliens to be in an atmosphere suit, typically very high tech (thin and floating). In extreme cases, the suit would encase the whole body in gel fluid and also inject it into lungs and other orifices to withstand pressures from different gravities or ship acceleration.
In essence, you need a lot of tech to allow diverse aliens to spatially co-exist.
Edit: All of this ignores food. Typically, stories solve that with some kind of nano-replicator that can make any combination of chemicals safe for aliens to eat.
The fastest spacecraft ever built would take 4000 years to travel one light year.
In 4000 years we can build way way more faster ships and catch up to those poor guys launched a centuries earlier just because they thought they are fast enough :) On the serious side, we only need antimatter and the drive problem is kind of solved (yes, I might be the one in the good enough ship :)).
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150 years by what calculations? Are you also factoring in deceleration time?
An "EmDrive" is a pseudoscience device. Poor calculation rigor is not the biggest error component in that number.
So you need a reactionless drive, which thus far is entirely science fiction.
This is even before you start thinking about micrometeorites in the way (which long transits increase the danger from), and simply maintaining complex machines in perfect working order for decades or centuries in the harsh vacuum of interstellar space with no external power source (no solar panels).
And that's before you start thinking about how we don't even know how to colonize an alien world, and unless you're willing to wait centuries to get intelligence on the planets you're flying in blind.
IMHO the answer to the Fermi Paradox is the most depressing one. Interstellar travel is too difficult and expensive. By the time it's feasible you are already well past the point of needing it. You can build endless orbital colonies and mine your home system and it's nearly unlimited resources forever. There is no need to embark on a colossally expensive boondoggle to colonize a distant solar system when everything you need is at home.
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I guess you're right. I know there aren't any observed transits, but I also don't know what the current constraints from monitoring the star's brightness for transit is (the star is actually so bright that it becomes hard to monitor for planet transits). However, we have a good prior on the inclination of these planets, because we know the inclination of the dust disk around the star ( https://www.scientificamerican.…
Since they are watching the star wobble, they probably have exact inclinations.
If we could hit 50% speed of light we could do a fly-by mission in ~25 years. Then another 12 years waiting for the data. Honestly, ~37-40 years isn't bad for an interstellar mission. Remember the Voyager program has been going on for that long! So we already have experience with long space missions.
https://breakthroughinitiatives.org/Initiative/3 https://en.wikipedia.org/wiki/Breakthrough_Initiatives#Break...