02-08-2018, 07:43 AM

(02-08-2018, 05:57 AM)Rynn Wrote: Welcome to the forums what's your favourite part of OA?

That's not the correct way to calculate the flight time of such a journey no. Exhaust velocity relates to thrust but you can't use it to derive travel time directly. For that you need to know the velocity of the craft, though in a lot of science fiction (and OA) rockets exist that have enough delta-V to accelerate for the whole journey. This equation works out how much time an object would take to cross a given distance at constant acceleration:

t = sqrt(2d/a)

Where d is distance in metres, a is acceleration in metres per second, t is time in seconds. This equation isn't for a journey however, it assumes the object constantly accelerates. It's good for working out fly-bys or impacts. Assuming we want the payload to arrive in one piece it needs to flip over half way and decelerate. In which case we just work out the equation above for half the distance and then double it:

t = sqrt(d/a)*2

This website does the calculation automatically for you:

http://www.transhuman.talktalk.net/iw/TravTime.htm

For a mean distance trip to Mars a spacecraft able to maintain a constant 10 centigee acceleration would do the journey in just under 12 days.

Thank You, I love the hardness of the universe and the devotion to scientific realism without ruining the fun. For the last year I've been becoming increasingly addicted to Hard Science Fiction; of course I don't hate softer franchises like Star Wars, Star Trek, etc, but I can't watch A New Hope without thinking to myself about how unrealistic it all is. And don't get me started on the "Parsecs" quote, dear god! I love the aliens, original and not just Humans with prosthetics (even genuine hard sci-fi series do that). The Encyclopedia Galactica is very informative, though I'm not really a fan of the Bernd Helfert artwork, it doesn't really fit. I would like to see more original artwork in the Encyclopedia. The History is not bad, I like the basic set up; The Singularity > Nanodisaster > Technocalypse > Great Expulsion > Dark Age. I don't agree with some of the Transhumanist elements in the universe, I think sentient AI will exist but I don't know if they'll become godlike entities within the next several millennia. Definitely not within the next 15 years as Ray Kurzweil and Elon Musk propose. Clarktech/Godtech seem like a stretch, though the Wormholes are cool.

I expect that Provolved Tree Kangaroos exist in Y11k.

Thanks for the equations, I've used these before. I just wanted to find an easily way to calculate travel time of a spacecraft without getting into the complicated equations. I've been looking up equations from Atomic Rockets and translating them into Wolfram Alpha with mixed results. I like the calculator you sent me, wish it was more interactive it seems very limited.

I other news, did you watch the Falcon Heavy launch yesterday. Absolutely beautiful! The Tesla Roadster sent into orbit, (the dummy driving it has gotten the nickname Starman) I've been seeing it reference all over Reddit and 4chan.

What did you think of the launch?