Rocket thread! Talk about space (mainly rockets and the iss with space programs) and share images!

Ion engines, but the thrust of everything we have working is terrible

Theres nothing better you can do with ion engines, they are limited by availible electricity

>all this retarded popsci bullshit

ion engine is more efficien in delta v terms? like, for the same mass you get more delta v?

how bad can the thrust be? doesnt that mean that it just takes more time to accelerate ? why not just make it go brachistrochorne and accelerate till halfway then decelerate till it gets to mars?

could it be improved by massive solar cells or would the added weight be too much of a penalty?, how about making it run on a nuclear reactor?

what about it? im not claiming anything, im just asking questions, why not just put your take on it, just say "this is impossible, this is not feasible because... " that would be very interesting and i would greatly appreciate it. I dont really see the point of you coming here just to complain

but gotta admit ilolled at your picture. I think your skepticism woul dbe greatly apreciated in this thread i made also:

Not true, there are engines in development with much better thrust but still have a plausible power draw, or you could just get the power from a nuclear reactor

>much better thrust
while keeping the same isp benefits?

>ion engine is more efficien in delta v terms
Efficiency is measured in ISP, to get more delta-v you just add more fuel

>how bad can the thrust be?
Dawn, which has over 10km/s of delta-v, has 3 ion engines on it. Each produces less than 1 newton of thrust, and it only fires one at a time. It accelerates constantly for months at a time

>could it be improved by massive solar cells or would the added weight
Weight is a big issue with current gen ion thrusters due to the low thrust

en.wikipedia.org/wiki/Magnetoplasmadynamic_thruster

If they get this thing to work then yes

They can build bigger engines, maybe with better thrust to weight, but its still a question of electricity & their efficiency turning it into thrust.

Meanwhile chemical engines can dump their thrust in LEO to take advantage of oberth effect, and travel direct to their destination.

Noone has built any space nuclear reactors yet, I suspect it would probably be more weight efficient to use solar panels anyways.

is it possible to join this field with a physics major? if so, where could I go?

I'm from whiteland though I'm okay with travelling to another country.

>Efficiency is measured in ISP, to get more delta-v you just add more fuel
your right of course, what i meant is more delta-v for the same total weight of the craft

>a question of electricity & their efficiency
is massive amounts of solar panels a solution? how about a nuclear reactor? batteries? a diesel reactor?

Its really just a question of which option gets the needed delta-v for the least amount of money, and at this point its an open question, although on paper at least chemical rockets are not the best method

Ion engines get far more delta-v than chemical engines for the same amount of mass

>is massive amounts of solar panels a solution?
This is where Dawn gets its power, but weight is a big issue

i know but how do they measure with nervas?

how about orion and other types of nuclear propulsion?

is there a theoretycal limit for electric propulsion?
it all boils down to how fast they can accelerate the particle right?

> measure with nervas?
Still a lot better, but nerva is a decent compromise between ISP and thrust to weight

>is there a theoretycal limit for electric propulsion?
I have no idea

>it all boils down to how fast they can accelerate the particle right?
Partly, but also how many particles you expel at once

I think NASA should focus on is building nuclear thermal upper stages for commercial rockets
Thats certainly a way to keep America's lead on rocketry.

i kinda agree, its quicker. But if electric propulsion can achieve higher ISP¨while mantaining decent thrust its a no brainer...

nasa is too dependant upon public opinion, and nuclear energy just has too much of a bad rep.

Space Shuttle booster rockets were modified Peacekeeper ICBM's. They were modified for parachute recovery. All of the Peacekeeper ICBM's have been deactivated. Once a year, people from FE Warren AFB in Wyoming would send one to Vandenberg CA to launch toward the Kwajalein Test Range.

High thrust ion engines are a long way away if they are realistic at all. Nuke engines are the logical choice for interplanetary missions in the near future. Also I use them in KSP so that proves it

Electric engines are most efficient at high Isp, which means very low thrust

Anyways NERVA engines are potentially in thousands of megawatts, whereas electric engines are like 200 kilowatts. I think they WILL be used as extra Isp during the trip to mars but not the main source of deltaV

But nuke engines get enough thrust and delta-v on their own

?
nuke engines are nerva

Nerva was one specific american project to design a nuke engine.It wasnt the only one, and it is not the one currently in place. America doesnt have a monopoly on the nuclear rocket concept

I would say Saturn or the shuttle

when we say nuclear propulsion we mean nerva engine, which means a nuclear reactor that directly heats the propellant before expelling it. The exhaust is radioactive

there is another more literally nuclear drive that uses actual nuclear bombs to propel itself, but thats unfeasible for now, for obvious reasons

there is also the more interesting choice of a nuclear reactor that generates electricty which in itself is used to power an ion drive, i wonder how that looks like

>saturn
yeah, you would need something as big as the saturn to feel something at this point

If the sts program did work meaning that the shuttle was orbiting the moon, we would have nuclear engines

Orion isnt actually unfeasible, its just that no one has the balls to try it, for obvious reasons

The US government killed nuke engines so they wouldnt be commited to a few more decades of the space race. That shit is expensive and they had already won

political and economical feasibility is also a thing

theres no way they'd let you take off with an orion from earth, the most you would get is an orbitally constructed orion or a ton of chemical boosters to get it to higher orbit

either way its a project that cannot be done in a small scale, even the most modest orion drive would be a HUGE investment in infrastructure, R&D and manufacturing. Like, in practice it would be a lot cheaper in terms of say.. $/kg to the moon or to mars, but the cost of it would be like another apollo program, maybe more who knows its just a big ass project no matter how you see it

The Soviets on by most accomplishments
But the space race was good. They made a Saturn v every 6 or so months now it takes a lot longer for SLS. The space race was good.

Won***

>The Soviets on by most accomplishments
At the end of a war you dont tally up the numbers of battles won by each side to determine the winner

>The Soviets on by most accomplishments
personally, from a scientifc and personal point of view i agree. The soviets, with a budget a really small fraction of that which american had accomplished everything except the moon landings, some of it first, most of it using really clever technology, they even invented the safest method of LEO space travel known to this day, which is actually the only current way to get to the ISS

On another interesting note, there was a very realistic, very possible project of a Soyuz moon landing(the soyuz was designed for this purpose originally) using already tested technology

the trick was to assemble the craft in orbit using proton rockets (which were already proven to work just fine). Too bad Serguéi Koroliov, who favored this approach, died tragically.

Then they just blew most of their moon mission money on the N1 tests, and it is a real pity because if they had just go on with their "smart" plan they originally had instead of their "brute force" aproach they did later, they might have made it
That being said, the space race was essentially a propaganda race, and the moon landings make the US undisputable winners of it from this point of view.

>theres no way they'd let you take off with an orion from earth
With a media blitz teaching people the negligibility of "fallout" threat, or an actual need to do it, it could easily happen.

>even the most modest orion drive would be a HUGE investment in infrastructure, R&D and manufacturing.
Not really, its just a matter of starting up the production lines for nuclear bombs again.
Or using the existing stockpiles of plutonium.

I don't know why you think it would cost so much money, theres no real development of new technologies needed, more a matter of alloting the budget.

If you need to go somewhere in a hurry, there is nothing with the Isp or the thrust of a Nuclear Pulse rocket

>The exhaust is radioactive
No it isn't
It's just exposed to the heat of the reactor

Soviets truly are some of the best at spaceflight at a lot of it. The space shuttle was amazing but it killed more than 14 people that is astronauts+ civilians. Soyuz was more reliable as it had a escape mechanism that did not rely on staging times and it can be adjusted. Soyuz ≠ Shuttle

>No it isn't It's just exposed to the heat of the reactor
It is actually. How do you think a nuclear reactor would heat something up that much without irradiating it?

>Not really, its just a matter of starting up the production lines for nuclear bombs again.

yes, if you start from the idea that you can take off with nukes then maybe

but that would be a REALLY REALLY REALLY hard sell to the public, dont you think the us goverment doesnt try to make people more nuclear friendly, they tried for ages, but people are just too stupid, they think they know more about radioactivity than the scientist

so maybe MAYBE you could sell the public that youre gonna put a couple of nukes in orbit but that they will explode far far away from their precious blue marble (lets not even get into the salt treaty) but no way youre gonna convince them to do a nuke take off, so that means that you have to put in orbit a fully supplied orion vessel with all the nukes via chemical rockets, that will be expensive

what do you think of the soviet moonshot project?

dont you think that it would have been kinda feasible to do it, i mean imagine just 3-4 proton rockets and you have the assembly in orbit, they could have used a soyuz as command module and that shitty one person lander they designed

why do you think they didnt do it?

Russia designed stuff to be compact and have a use. I would not care to much that I am in a small space but I would be scared of the unknown

> I would not care to much that I am in a small space
You might after a few days of it

It gets heated by the reactor to 2000 degrees, its not made radioactive

I think you greatly overestimate how relevant popular support is, even in a democracy.
For now I believe republicans might be holding nuclear back because they are coal/oil shills, and because Obama was pro-nuclear.

I would because I am lonly. And I would.

actually, all current spaceships are essentially claustrophobic and will continue to be for a long time. the difference between one and another couldnt have been more than a few cubic meters.

Travelling in the soyuz is like being buried alive for a couple of days, true story

Op here
I admit defeat
I am more interested in the iss and space shuttle o rings

>It gets heated by the reactor to 2000 degrees, its not made radioactive
Once again, how do you suppose it is possible to get fuel close enough to a nuclear reactor to heat it to 2000 degrees without irradiating it?

youre not op, im op

Uh, im pretty sure i'm op

I'm op I am positive.

You think civilian nuclear reactors make millions of gallons of water radioactive?

fuck you guys its not funny

ok then

so, the main question here is ...

WILL ELON MUSK SUCCEED?

WHEN will the first falcon refly

WHEN will they be 99% sure they can recover boosters

HOW MANY times will the boosters be able to refly

HOW MUCH will it really cut down costs?

Civilian reactors dont pass the working fluid through the reactor core

>WILL ELON MUSK SUCCEED?
BE MORE SPECIFIC

>WHEN will the first falcon refly
50/50 before the end of the year

>WHEN will they be 99% sure they can recover boosters
When they start routinely recovering them

>HOW MANY times will the boosters be able to refly
Maybe 10 or so times if they are lucky

>HOW MUCH will it really cut down costs?
By half maybe, but not for a while and that will be quite a stretch

civilian reactors only need to heat water to make it go trough a turbine

a spaceship reactor needs to get the fucking propellant as fucking hot as fucking physically possible without fucking fuck shit melting the fucking ship itself

every percentage of a fraction of a portion of a degree celsius that the propellant is not heated up to becomes a loss in delta v

I don't see any mention at all of solid core NTR design causing radioactive exhaust
Things do not magically become radioactive just because they were exposed to radiation

Will be by far more than half, what SpaceX charges isn't what it costs them.
I believe they will have a reusable upper stage soon

So rapidly it's going to turn into how fast they can launch rockets.

>I don't see any mention at all of solid core NTR design causing radioactive exhaust
web.stanford.edu/~rhamerly/cgi-bin/Ph241-1/Ph241-1.php
"While the rocket is designed to avoid radioactive leakage products, inevitably a small amount of radioactive waste will make it into the rocket's exhaust"

>Things do not magically become radioactive just because they were exposed to radiation
?!?!?!?!!?!?!?!?

I dont care about fanboy pipe dreams

I got a question; what if STS 27 lost another tile?

are the barge and land landings pipedreams?

everythings a pipe dream in space travel, anything is wacky until it gets done

Agreed
But then explain the odds of STS 51l and 107 happening again

Look like the radioactive exhaust is being made by pieces of the reactor call degrading/falling off
Possibly could be eliminated or greatly reduced
Radiation is one of those hugely overstated issues anyways

reactor core*

Oh im not saying the radiation is particularly bad or worth worrying about, just the fact that it is there. That report also mentions that a 340 day trip to mars is expected to deliver 5 rems to the astronauts from the engines

I would make it so there is a layer of lead that is thin but can reduce radiation

>I would make it so there is a layer of lead that is thin but can reduce radiation
The thinner it is, the less radiation it absorbs. All spacecraft have this anyway, space is full of radiation

It's impact can be described like this: imagine one snowflake then a snowstorm a small thing can make a large impact

Thats a question of shielding & proximity to the engine

Or a changeable sheet. I would work on radiation proofing stuff

Its space, you go with whatever option does the job for the least amount of weight

I can not agree more.
Was there ever a ares launch?

if that were true we would have nuclear spacecraft in 1955, germans already knew how to build em

but its not
politics goes against economics sometimes

And money ruined a moon colony or the space shuttle visiting the moon

>space shuttle visiting the moon
please tell me there were real plans for that, taht would have been cool as fuck

is it me or is the space shuttle built to look cool, it is by far the nicest looking spacecraft ever

maybe its the fact that its aerodynamic, skylon also looks cool to bad its not real

One day my friend, one day

You have a stupid interest OP.

The year is 2045,somehow youre still alive...

you check your email

SURPRISE YOU HAVE BEEN WON A SPECIAL CONTEST WHICH MAKES YOU GO TO SPACE

this is very lucky for you, since most working or middle class people who live on earth usually dont go to space...
and to think that a ticket to luna is almost THREE TIMES as expensive as an airplane ticket to japan!, thats a lot of money indeed who can spend that? not many people unless you have job or family there

ok, this means they will either put you on a reusable rocket or one of those skylon spaceplanes, they both been competing head to head since space became viable for civilians, they say skylons are safers, but a rocket sounds cooler, i hope i get the rocket

anyway, that will probably take me to one of the LEO node from where i will catch the ion ferry to luna, or maybe mars, who knows?? oh gee im so excited to live in the time when humans became intelligent and decided to put down their stupid actions like war and put up their god tier actions like science

Why must you make me feel these feels?

the pain, it makes us strong, it makes us go on with more passion

At least two empties, I'd think.
>Also depends what you mean by "left"

There are none left because no one has ever been to space, its all a lie to allow nasa to steal my tax dollars

implying the goverment needs a lie as complex as the space program to steal your measly illiterate redneck salary whole

i mean jesus, most of the people in the country give money to a guy only because jesus said so, and that is objectively confirmed by science to be a false non truth opposite of reality fairy tale

>are most efficient at high Isp

Is this not tautological?

yeah, this guy knows
youre falsely indicating that high isp must always necesarily mean low thrust

it kinda TENDs to be like it, but its not necesarily like that

I have a question... is NASA any better than it used to be? I read Richard Feynman's report on the challenger disaster and the management sounded like shit

its easy to talk shit about nasa, it now has the same amount of money as any other scientific endeavour

back in the cold war day it had FUCKING 5% OF ALL OF AMERICAS MONEY

i think even a retard could have gotten to the moon on that budget

>engines are most efficient at high Isp
This really depends on what you mean by "efficient." High ISP demands less propellant mass per unit of impulse, but actually requires more energy per unit of impulse. So, with a limited but steady power input (i.e. solar panels), you can either feed propellant to it slowly and eject it at high velocity providing low thrust at high ISP (i.e. ion engines), or you can feed it more quickly producing greater thrust at lower exhaust velocity and ISP (i.e. thermal rockets).