Continue to Site

# NASA Apollo 11 space mission to the moon.

Status
Not open for further replies.

#### alright1234

##### New Member
How much fuel was used to decelerate the 983 m/s CMSL at the moon?

Who knows?
Who cares?

But I bet they got a lot of points on their TESCO ClubCard when they filled up with petrol before they set off.

JimB

I am sure there was someone in the control worried about that.

NASA has a lot of info in their site. Try there.

NASA used to have specific links (IIRC, email adresses) for you to ask questions. I recall doing so twice and the answers were quite complete.

I did my own calculation and got---->

The amount of fuel required to decelerate the Apollo 11 Command/Service Module (CSM) and Lander (L) after reaching the moon is calculated. The kinetic energy of Apollo 11 command-service module and lander (CSML) that is propagating to the moon is calculated using the distance to the moon (363,104,000 m) and the time that the Apollo 11 space craft (CSML) propagated to the moon (4 days 6 hours and 45 minutes [364,900 seconds]),

v = (distance)/(time) = (363,104,000 m)/(364,900 s) = 983 m/s.......................................................85

The total mass of the command, service modules and lander (CSML) is,

(CM) + (SM) + (L) = 5,560 kg + 24,520 kg + 16,400 kg = 49,480 kg................................................86

Using equations 85 an 86, the kinetic energy of the Apollo 11 CSML is calculated,

1/2 mv2 = (.5)(49,480 kg)(983 m/s)2 = 2.39 x 1010 J.........................................................................87

Using the kinetic energy of the CSML (equ 87) and the energy of a kilogram of rocket fuel (4.2 x 107 J/kg), the minimum amount of fuel required to decelerate the CSML is calculated,

Fuel mass = (KE)/(fuel energy) = (2.39 x 1010 J)/(4.2 x 107 J/kg) = 569 kg...................................88

Using the rocket engine efficiency of 1% and the result of equation 88,

(569 kg)/X = .01 -------------> X = 56,900 kg......................................................................................89

Now that at 1% efficiency. At .1% efficiency it would be a whopping 500,000 kg and I even seen a value of .01 efficiency. See all that smoke during the space shuttle take off. Very inefficient.

From infinity and beyond your friend and Jedi knight

alright1234.

So, what are you saying?
ELI5.

Here is a BBC doc regarding the Apollo 11 mission.

BBC Doc.....you serious??
I tried to watch, but gave up at around t=5:30, after rolling eyes for a few mins prior to that....
Too much religious propaganda for it to be a legit BBC production.

Now that at 1% efficiency. At .1% efficiency it would be a whopping 500,000 kg and I even seen a value of .01 efficiency. See all that smoke during the space shuttle take off. Very inefficient.

A straw man argument and not worth a serious response.

After all that do we actually have an answer and is it a credible answer?

After all that do we actually have an answer and is it a credible answer?

Why would you expect an answer to a completely stupid question?

Fuel mass = (KE)/(fuel energy) = (2.39 x 1010 J)/(4.2 x 107 J/kg) = 569 kg...................................88
This assumes the CSML was brought to a complete stop and ignores the fact that the CSM part continued in orbit round the moon.

some of the calculations are incorrect because you are assuming the lunar orbital velocity is the same as the translunar velocity. you are also not figuring in the acceleration of lunar gravity which is 1/6 that of earth or 1.35 ms^2

also, the "efficiency" numbers are totally bogus, because rocket performance is measured with "specific impulse", which takes into account combustion product mass, nozzle velocity, and the expansion ratio on the low pressure side of the nozzle.

i've been wondering why there are so many bogus theories on a large number of technical and science subjects. i am beginning to think that the scientific method is not being taught at all anymore, or if it is, it's being taught with a subjectivist slant. it's as if the scientific method has been altered to read:
1) something is observed that isn't understood
2) develop a hypothesis
3) run an experiment and record the data
4) keep all data that supports the hypothesis, and reject all data that does not
5) if the hypothesis isn't supported, devise a new experiment and go to step 3, if the hypothesis is supported, publish the hypothesis.

Personally, I think it's just too many gullible teenagers / young adults looking at youtube videos and conspiracy site posts from trolls, who get some kind of kick out of making nonsense claims and getting people to believe them...

i am beginning to think that the scientific method is not being taught at all anymore,
Correct.

i am beginning to think that the scientific method is not being taught at all anymore,
IMO, the problem is largely due to political correctness, "everyone is included", medals just for participation, bowing to the demands of SJW's, and a growing number of other factors which, when combined, continue to erode the ideas and principles which science has been based upon for eons.
Naming conventions have come under attack, and now we can apparently no longer assign a particular gender to pins and sockets. They have been called "Male" and "Female" for Deity-knows-how-long, but someone got triggered:

Do we have to simply fold and now call them LGBTQI connectors, re-engineer them to connect in any possible combination of protruding/hollow styles at substantial cost, or do we draw a line and tell "Princess" to suck it up? If she is triggered so easily by pin/socket naming, maybe "Dance therapy" would have been a better degree to pursue.

BTW, no offence is intended toward any of the ETO membership, or guests viewing, who are of the LGBTQI community, in the example above.

Post #19.... Yup.

Here I go.
(Runs into the tunnel with tracks that has a strange loud rumble and an air horn? And ohh look a light way down there, wonder what that could be? )

Issues locally near me have resulted in the abbreviated terminology (Female terminal / Male Terminal) that implies FT and MT. Thus including the placement of the parts list context order as follows, must list the FT (part number) first if a female terminology part is included in the parts list then any MT (part number) .

This... this has been quite complex for many to follow. I just nod and go yup.... Head drops as in suddenly looking down are considered a form of Ostracism, that I can yet to correctly determine as to what "they" assume that to mean. I think "they" are referring to some form of malformed emotional abuse?

As for Science, was removed from that class and promptly informed by school staff that I was not going to get an easy ride in that school as I made the mistake of being actually wanting to be in that class and as a result I was mistaken in taking that class seriously.

Just played the system by being D - C avg then every EOG 92-95 %. I was even special enough that towards the end of that place I was taking the test on a separate form type from the other 2 different types of test to reduce cheating.

That was something. (most just wanted their "demeaning" paycheck and "turn screwdriver" the rest)

Status
Not open for further replies.