Propellant Definition and 25 Threads

Orbits around the Lagrange point are not stable, and you need to tweak your trajectory every now and then to remain in that orbit. Simulations of a non-accelerated body give spectacularly weird results: When the propellant runs out, is this what the JWST will do?

Now this is how I've tried to solve this $$ v_e = u0 \cdot ln \frac {M} {M- μ \cdot t} $$ After putting in the values I get this; $$ v_e = 200 * ln 0,36 $$ $$ v_e = 73,54 \frac m s $$ Now I'd say that this is the correct way to do it, but this part is confusing me "What is the speed of the...

Rocketry is not good enough for the standard scifi spaceship that can take off and land like it pleases with high payloads. Yet I still like rocketry because I like the fiery exhaust plumes. So I am considering linking the spaceship's rocket engine to a portal linked to to a planetary...

Black powder has specific impulse of around 80s, while rocket candy has up to 130s of specific impulse. Does that mean I could replace the propellant in a BP cartridge with 80/130 of the weight in rocket candy and obtain the same performance in an idealized gun? (as in without considering...

Is it possible to pressurize a spray can with gunpowder or something similar, in order to make a reliable spray can with high pressure? I’m asking this question because a small amount of gunpowder generates a huge amount of propelling gasses when ignited. I need to make a compact spray can...

I would think that the use of triple base propellants in hand-held weapons, such as assault rifles or pistols, would be greatly beneficial as its use would remove the muzzle flash. Also, it would decrease wear-and-tear on the weapon itself, I would think. I have found some people saying that...

Homework Statement [/B] I was wondering if you'd be able to help me with this problem: Given a two-stage launch vehicle with an engine that produces an Isp =400 sec, a payload mass of 10.000 kg, stage 1 structure mass of 10.000 kg, stage 2 structure mass of 10.000 kg, determine the mass ratio...

Time and again one comes across various authors using the sentence "" by the principles of propellant chemistry"", in order to determine the ratios of the complexant (fuel, like glycene, citric acid etc) and the metal salt, in preparatioin of ferrites by sol gel technology. Say for example in...

For the past year or so, I've been experimenting with Isobutane. I used to get it in relatively cheap canisters of r600a from amazon.com and AliExpress, and that worked fine. Now, however, AliExpress has NO purchase options for r600a, and amazon.com will not ship it to the US, even though they...

I want to ask about the differences between a photon rocket and a rocket which uses conventional propellant. A conventional rocket shoots exhaust matter out the back end, resulting in impulse and acceleration. A photon rocket shoots photons out the back end, resulting in impulse and...

Homework Statement Consider a cryogenic chemical propulsion system with Isp (specific impulse) = 450 s Enter the required propellant fraction as a proportion with at least two decimal places. The ΔVelocity is provided. ΔV = 9.6 km/s Homework Equations Rocket equation: ΔV = Vex x Ln (initial...

Ok, I am really close to this. d-Limonene dissolves Polystyrene (I have tested this) and Liquid Isobutane mixes with d-Limonene (I have also tested this) However, when I mix all three together, the Polystyrene becomes completely separated from the solution. Same thing with all polymer solutions...

Let's say a ship is beyond Earth's meaningful gravity pull, and has solar panels. Assume that it can collect solar power and use it in a system which blasts propellant away from the ship to accelerate through space. The ship's goal is to leave the solar system and reach a new star, but to...

This is a ridiculously easy question, so I apologize for bugging you all with it, but google has been less than helpful. Consistently when I watch videos of rocket launches I hear operators talking about propellant utilization being active (usually with individual stages singled out). What does...

The Swedish SMART-1 used a Hall effect thruster which used Xenon gas. Xenon costs 1200 USD per Kg. Why didn't they use Helium instead which costs 50 USD per Kg? New Horizons probe launch in 2006 used a Radioisotope Thermoelectric Generator which used Americium-241. Americium cost 1,5 million...

A livestream video feed from the event has started and can be accessed via the CS homepage [1] or the corresponding blog on Wired [2]. Some background information about CS can be found on [3] together with a (very) short description on the TM65 [4]. [1] http://www.copenhagensuborbitals.com/ [2]...

I've been doing some reading about Orion-drive spacecraft , but I don't understand the requirement of a high Z propellant like tungsten. Assuming that the pulse unit were detonated further away from the craft to prevent it from drilling a hole in the pusher plate due to its narrower angle, why...

Can hydrogen be burned and used to drive an engine?

Homework Statement What is the average acceleration until burnout of a spacecraft engine creating 53.2MN of thrust with a propellant velocity of 4.78km/s? The initial mass is 2.12x10^6 kg and final ,*** is 7.04x10^4. Homework Equations 0 = m(subscript_f)v(_f) + m(_r)v(_r) The...

Hi, I am new to building large candy rockets, and I have a target of building a candy rocket that can reach an altitude of over 40,000ft. I am mostly concerned with the safety when casting such propellants. I am looking at casting over 200 pounds of propellant. Any one got any advice. I have...

Homework Statement An astronaut in his space suit and with a propulsion unit (empty of its gas propellant) strapped to his back has a mass of 143 kg. During a space-walk, the unit, which has been filled with propellant gas, ejects some gas with a velocity of +30.9 m/s. As a result, the...

I have been flying some model rockets powered by commercially available solid propellant engines. I have been flying at an elevation of 2550 above sea level. I am headed to a competition next week and will be flying near sea level. The air density will change approximately 5% due to the...

Has arrived, eventually. http://www.sci.esa.int/science-e/www/area/index.cfm?fareaid=10 propulsion details here:http://www.sci.esa.int/science-e/www/object/index.cfm?fobjectid=34201

Eventually, if we want to establish outposts in our solar system, starting with the Moon, we will need a continuous source of propellants. A space station in LEO and in lunar orbit would be needed. Let's say the propellant of choice is hydrogen and oxygen. What would be the best way of getting...

I was bored earlier today, so I concluded the best way to elevate my boredom was to exercise my brain for next quarter. The best way to exercise your brain is to do a little physics, right? I started to think of a problem. I came up with a classic projectile problem: A cannon fires a...