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[-] RobotToaster@mander.xyz 88 points 5 days ago

just 40 light-years from Earth

The word "just" is doing a lot of work here.

[-] arken@lemmy.world 55 points 5 days ago

One of the more optimistic estimates in this thread is that it would take us ~60 000 years to travel with existing technology.

Of course, now that we have ChatGPT, Gemini and Grok we're obviously gonna reach light speed travel within the next 10 years, so it won't be a problem.

[-] CarbonIceDragon@pawb.social 21 points 5 days ago

I mean, saying it would take half of forever with existing technology, when we do not have the technology to do it in the first place, seems a bit redundant. There are any number of hypothetical technologies for travel to relatively nearby stars that, while we don't have them presently, at least do not violate physics and are more an issue of requiring a civilization of much larger scale than ours to afford to build them rather than one of if they're physically possible.

An analogy I once saw was this: suppose you were to go back in time to meet a medieval blacksmith, and you show him the blueprints for a modern jetliner. You might, with a lot of explaining of the relevant physics and engineering behind all the parts, be able to convince the guy that the machine could work if constructed. But, he'd have no idea of the process for how many of the parts are made, or the materials they're made from, and if you included all that information too, the whole process would be so expensive and the size of the economy back then so small that in all likelihood, not even the richest kingdom on earth in his day could possibly afford to actually build and operate one. However, if the blacksmith took all that information and concluded "this can never happen, it's just too hard", time would prove him wrong.

[-] iAvicenna@lemmy.world 11 points 5 days ago* (last edited 5 days ago)

Achieving a velocity of 0.5 times the speed of light (ccc) for space travel involves solving advanced challenges in physics and engineering. The Python script below creates a simplified optimization framework to analyze the propulsion needed. It uses physics principles like relativistic mass-energy equivalence and propulsion mechanisms such as fusion or antimatter engines.

This code assumes you have the theoretical fuel and energy to achieve the speed, but it abstracts away complex challenges like time dilation, cosmic radiation, and material limitations.

Python Code

import numpy as np
import matplotlib.pyplot as plt

# Constants
c = 3e8  # Speed of light (m/s)
target_speed = 0.5 * c  # Target speed (0.5c)
ship_mass = 1e5  # Mass of the spacecraft without fuel (kg)
fuel_efficiency = 1e-3  # Fuel conversion efficiency (e.g., antimatter ~0.1, fusion ~0.001)
exhaust_velocity = 1e7  # Exhaust velocity of the propulsion system (m/s)
specific_impulse = exhaust_velocity / 9.81  # Specific impulse (seconds)

# Functions
def relativistic_mass(speed, rest_mass):
    """Calculate relativistic mass."""
    gamma = 1 / np.sqrt(1 - (speed / c) ** 2)
    return gamma * rest_mass

def fuel_needed(final_speed, ship_mass, exhaust_velocity):
    """Estimate fuel required using the Tsiolkovsky rocket equation."""
    delta_v = final_speed
    mass_ratio = np.exp(delta_v / exhaust_velocity)
    fuel_mass = ship_mass * (mass_ratio - 1)
    return fuel_mass

# Optimization
def optimize_propulsion(target_speed, ship_mass, exhaust_velocity, fuel_efficiency):
    fuel_mass = fuel_needed(target_speed, ship_mass, exhaust_velocity)
    energy_required = fuel_mass * fuel_efficiency * c**2  # Total energy for propulsion
    return fuel_mass, energy_required

# Perform calculations
fuel_mass, energy_required = optimize_propulsion(target_speed, ship_mass, exhaust_velocity, fuel_efficiency)

# Display results
print(f"Target speed: {target_speed / c:.2f}c")
print(f"Required fuel mass: {fuel_mass:.2e} kg")
print(f"Energy required: {energy_required:.2e} joules")

# Visualization
speeds = np.linspace(0, 0.5 * c, 100)
fuel_masses = [fuel_needed(speed, ship_mass, exhaust_velocity) for speed in speeds]

plt.figure(figsize=(10, 6))
plt.plot(speeds / c, fuel_masses, label='Fuel Mass Required')
plt.xlabel('Speed as a Fraction of Light Speed (v/c)')
plt.ylabel('Fuel Mass (kg)')
plt.title('Fuel Requirement vs. Speed')
plt.legend()
plt.grid()
plt.show()

How it Works:

Relativistic Mass: Accounts for relativistic effects as the spacecraft approaches significant fractions of the speed of light.
Tsiolkovsky Rocket Equation: Estimates fuel requirements based on the propulsion system's exhaust velocity and initial mass.
Energy Requirement: Evaluates energy needs assuming the specified fuel efficiency.

Limitations:

Idealized Assumptions: Assumes perfect efficiency and ignores engineering constraints.
Simplified Physics: Doesn't account for external factors like gravity, drag, or realistic propulsion systems.
Energy Storage: No consideration for how energy would be stored or delivered.

Would you like more refinement or details on specific subsystems?

FIRE ALL THE PHYSICISTS

[-] abbadon420@lemm.ee 10 points 5 days ago

perpetually within the next 10 years

[-] finley@lemm.ee 6 points 5 days ago

I think you’re forgetting Stargate technology…

[-] ThePowerOfGeek@lemmy.world 4 points 5 days ago

Grok 2.0 alone will move heaven and Earth to reach alien civilizations. It's sole reason for that will be to insult them. But hey, a motivation is a motivation.

[-] RunawayFixer@lemmy.world 8 points 4 days ago

I read a science fiction book from Iain M Banks over the holidays that was set in a rogue star system that was millions of light years away from the nearest galaxy. No matter how advanced that society could get, they would never be able to travel to the nearest star. They were doomed to isolation in their 1 star system basically. Compared to that, a mere 40 light-years at least gives the hope that it might one day be possible to travel there within a few life times (or less) of traveling.

[-] Telodzrum@lemmy.world 4 points 4 days ago
[-] RunawayFixer@lemmy.world 2 points 3 days ago

Against a dark background

[-] SlapnutsGT@lemmy.world 8 points 5 days ago

What do you mean? It’s just a quick 2.351 × 10^14 mile drive. No biggie

[-] scaramobo@lemmynsfw.com 6 points 5 days ago

Can Elon, Jeff, Mark, Bill and that Virgin Atlantic weirdo please quickly hop on the next Starship rocket and fly to that planet to check it out? Just a quick there-and-back? Have a looksy? Go on, you know, for mankind, be an(sic) hero...

[-] Gigasser@lemmy.world 4 points 5 days ago* (last edited 5 days ago)

Wouldn't we have to terraform that shit too? We can probably send a probe out there or some shit, maybe the "Breakthrough Starshot" concept would be able to do it in a few hundred years or some shit

[-] CarbonIceDragon@pawb.social 8 points 5 days ago

Terraforming would seem a bit unnecessary if you can send a crewed ship there. Manned interstellar travel, unless we're wrong about the whole speed of light thing, is going to take decades at least to reach the very nearest stars (I'd imagine that it is more likely we'd go to those stars first, and only reach Trappist when people from those stars later launch their own ships, until eventually the outer edge of settled space reaches 40ly).

That implies that, if you can send some colony ship to another star, you necessarily have the technology to build a space habitat that can sustain large numbers of humans in sufficient comfort to run a small civilization and all relevant industry, self-sufficiently using only the materials available in space from asteroids and such as inputs. You have this tech first, because the colony ship is itself just one or more of these habitats, on top of some massive propulsion system.

As such, why even bother with terraforming planets? That's a process that may potentially take millennia to truly finish, longer than it took your ship to even get there with some of the possible propulsion options, will only be viable on a fraction of worlds, and will still get you a place that probably does not have an earth like day or gravity or any number of other differences. You would then be back in the bottom of a gravity well, which requires a ton of energy expenditure to get back into space again. Why not instead, find some asteroids and comets in your target system, there's probably going to be some around somewhere if our solar system is any indication, and build more of those habitats as needed.

[-] TimeSquirrel@kbin.melroy.org 4 points 5 days ago

unless we're wrong about the whole speed of light thing

Technically, if we could reach relativistic speeds close to the speed of light, the trip could be very short for the crew. Just don't expect to ever be able to see anyone you knew back home ever again. We can do just fine on sub-FTL tech if the crew accepts the consequences. We can use very high ISP continuous propulsion methods like the Orion nuclear bomblet and pusher plate concept, or beefed up ion engines, or lasers pushing a solar sail, etc.

[-] RobotToaster@mander.xyz 4 points 5 days ago

You then just have to figure out how to stop, preferably without killing any life that may have already evolved there.

[-] CarbonIceDragon@pawb.social 1 points 5 days ago

Those are the ideas I was referencing as taking decades tbh. Technically a few, especially the laser sail, can potentially get to high enough fractions of lightspeed to get that noticable time dilation effect, but given that makes something that already costs a huge amount of energy, much more expensive than it already is, I'm not sure if you'd actually want to go to those speeds very often.

[-] Klnsfw@lemmynsfw.com 12 points 4 days ago

40 light years to reach a potentially habitable planet with a carbon dioxide-rich atmosphere?

Just wait 40 years on Earth.

[-] Tabula_stercore@lemmy.world 21 points 5 days ago

I must say I'm quite intrigued that we know it has beer before knowing it has a carbon atmosphere

[-] kreskin@lemmy.world 7 points 4 days ago

Maybe oceans of beer.

[-] Gsus4@mander.xyz 3 points 4 days ago* (last edited 4 days ago)

I'm not sure about beer (hah, I got it, the survey name), but vodka for sure: there are giant clouds of ethanol in space https://www.mentalfloss.com/article/51271/there-are-giant-clouds-alcohol-floating-space

Discovered in 1995 near the constellation Aquila, the cloud is 1000 times larger than the diameter of our solar system. It contains enough ethyl alcohol to fill 400 trillion trillion pints of beer. To down that much alcohol, every person on earth would have to drink 300,000 pints each day—for one billion years.

Sadly, for those of you planning an interstellar pub crawl, the cloud is 58 quadrillion miles away. It’s also a cocktail of 32 compounds, some of them as nasty as carbon monoxide, hydrogen cyanide, and ammonia.

Ok, so this vodka smells like old pish and bitter almonds :D

[-] PumpkinSkink@lemmy.world 21 points 5 days ago

I always like when people talk about potentially habitable exoplanets. It's like "this planet is not literally on fire or frozen solid, and it's atmosphere is 80% carbon dioxide with a measly 20% hydrochloric acid". Like we've got a planet here that we're struggling to not kill ourselves on from doubling the Co2 from 250 ppm to 500 ppm. We're never getting to that other planet, bro. If we were gonna, solving climate change would be trivial by comparison.

[-] very_well_lost@lemmy.world 23 points 5 days ago

Nobody is seriously looking for 'habitable' planets because they expect humanity will someday inhabit them — this is all about the hunt for other life out there in the universe.

To astronomers, "habitable" just means that the planet gets to correct amount of energy from its star that liquid water could potentially exist on its surface. Liquid water may not actually be a requirement for life, but since we only have a single data point to work from, it makes sense to look for the preconditions of the kind of life we're familiar with on earth, of which liquid water is a big one. (Another is carbon chemistry, so finding lots of atmospheric carbon isn't necessarily a bad thing when searching for other life out there.)

[-] SharkAttak@kbin.melroy.org 13 points 5 days ago

....................how thick? õ_O

[-] SkaveRat@discuss.tchncs.de 7 points 5 days ago

thicccccccc

[-] ian@feddit.uk 1 points 3 days ago

Oh great! The planet has already got a carbon dioxide atmosphere. So we can't go there and burn stuff to mess it up like web did to the last one.

[-] MonkderVierte@lemmy.ml 2 points 5 days ago

Tell again if it is.

[-] _sideffect@lemmy.world -4 points 5 days ago
[-] AmidFuror@fedia.io -1 points 5 days ago
[-] _sideffect@lemmy.world 0 points 4 days ago

Anal bum cover

this post was submitted on 31 Dec 2024
199 points (96.3% liked)

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