Apollo 11 - I have a question

I wrote this in a thread I had about Buzz Aldrin but the thread went down the tubes as they do.

I'll write this out first and ask my question at the end:

Okay, the Moon is 238,857 miles (284,403 kilometers) from the Earth.

Neil, Aldrin and Collins (first trip to the Moon)

Apollo11

Launched July 16, 1969 at 1332 GMT --- 09:32 a.m. EDT

Safely lands on the Moon July 20th at 2017 GMT ---0417 p.m. EDT

Neil steps on Moon at 0256 GMT ---10:56:15 p.m. EDT

Location --- Sea of Tranquility

They were there 21.6 hours and on the surface for a total of two and a half hours.

Left Moon's Orbit July 22 at 1750 GMT ---1:54 p.m. EDT

Landed back on Earth July 24th at 12:50 p.m. EDT

Duration: 8 days, 3 hours, 18 minutes, 35 seconds.

When I add this timing together it seems to work as a whole BUT my question is ---- why would it take four days 7 hours to get there and a nitch less then two days to get back? Am I missing something here?





[edit on 28-6-2007 by observe50]

Their velocity was greater on the return trip due to decreased spacecraft mass, and greater trans Earth injection V due to lower gravity of the moon?

Also, another minor point regarding your summary.... Apollo's 8 and 10 also went to the moon, but did not land.

Apollo 9 tested Command module/LEM docking proceures in Earth orbit.

I have to say that I don`t believe they went there in the first place.

Why.

NASA are currently developing the next trip to the moon and will take around 20yrs to put everything needed in place.

Why?

Can`t they just redevelop the original tech with obvious 21 centurary technology

Wasn't there a needed slingshot orbit around Earth needed to boost the speed? Maybe they included that in the itinerary?

Don't think there's anything especially suspicious in the time table. What did you have in mind?

I know of the others I guess I didn't write that correctly but I think most know what I'm talking about.

I think coming back two and a half days faster is a bit much myself, this is why I'm asking.

My thoughts are that they (NASA) times everything. People have questioned if they (Armstrong, Aldrin, Collins) even went to the Moon. Back in those days people didn't question stuff.

When I add the time it seems right but when I see it takes approximately 4 days and 7 hours to get there and like 47 hours to get back I wanted to question it.

There are so many people that know about this type of stuff here at ATS so I wanted to bring this up. To me, the return trip just seems off.

103 hours to get there and like 47 to get back.

nescafe,

I agree with you it doesn't make sense.

I don't know how I feel about all this. I always believed they went to the Moon. In my days we didn't question much of anything and if we were being shown and told this, we believed it, I don't think people back then thought about the government lying to them.

Times are different now and we have all kinds of technology. People have learned to question things and discovered that our governments are great in the lying department.

If the timing of getting there and getting back is doable (back then in 69) then maybe they did go. I would really like to know as I am sure millions of others are aslo.

Originally posted by observe50

Safely lands on the Moon July 20th at 2017 GMT ---0417 p.m. EDT

Neil steps on Moon at 0256 GMT ---10:56:15 p.m. EDT

i realize that time has a way of making memories fuzzy,

but didn't a camera televise the 'Eagle' spacecraft in less than
an hour after they landed??

i recall about 5PM, at the "Admiral Benbow's" on Conneticut Ave, having a bottle of Champagne & watching continuous Apollo 11 coverage - the talking heads at NASA, & the Big-3 TV-News, and then (if i recall correctly) a TV remote from Tranquility Base on the Moon...that afternoon.

[btw, the champagne wasn't for the moon landing, it was in celebration of a hippy marriage at 2PM that day]



?? - i was wondering what source you got the detail of the times from,
because i've searched before but never had it laid out, for the reason of jogging my memories of the events that day.

Here is the official Apollo11 Final Flight Plan from NASA. Maybe you can find your answers in it.

history.nasa.gov...

From what I found in a quick scan, the Trans Lunar coast took 73 hrs., while Trans Earth Coast took 59 Hrs. Like I said before this is most likely due to greater return V due to lower mass. Also the return trajectory was probably considerably shorter since Earth isn't a moving target, unlike the Moon.

A full day was spent in Lunar orbit before descent. That added a considerable amount time to your initial Earth to lunar landing time of 4 days.

Happy reading and good luck!

[edit on 6/28/2007 by darkbluesky]

sORRY, I should have put that in:

science.ksc.nasa.gov...

[edit on 28-6-2007 by webstra]

Don't forget that during the Earth-Moon trip you have the Earth's gravity holding you back during most of the trip while during the Moon-Earth trip you have the Earth's gravtiy pulling you in for most of the trip.

I was trying to compare with the previous test run Apollo 10 and trying to see if I found time for return.

So what I am gathering so far is I have a couple of you saying the timing is doable.

Approx. 103 to get there and approx. 47 to get back.

I hope others join in, I would like to get a few more opinions on this. What you are saying sounds logical, but I'm not fully convinced.

Originally posted by observe50

I hope others join in, I would like to get a few more opinions on this. What you are saying sounds logical, but I'm not fully convinced.

Is it your suspicion that the records are falsified and/or they never actually went to the moon?

Originally posted by Badge01
Wasn't there a needed slingshot orbit around Earth needed to boost the speed? Maybe they included that in the itinerary?

No, that doesn't work. You need a third body to get a gravity assist, and there isn't one in this case.

Originally posted by nescafe8572
I have to say that I don`t believe they went there in the first place.

Why.

NASA are currently developing the next trip to the moon and will take around 20yrs to put everything needed in place.

Why?

Can`t they just redevelop the original tech with obvious 21 centurary technology

The technology they used back then were like comparing a slinghot to a gun. (Well almost..)

So a lot more things has to be in place, but the benefit is that it is more safe I guess.

Originally posted by darkbluesky
Their velocity was greater on the return trip due to decreased spacecraft mass, and greater trans Earth injection V due to lower gravity of the moon?

Just a thought, but why would decreased mass matter in space?

Or am I being thick?

Originally posted by budski
Just a thought, but why would decreased mass matter in space?

Or am I being thick?

Not at all. It's not really that intuitive.

Force = Mass x acceleration

Therefore acceleration = force / mass

In rocketry, the force of the engine thrust is referred to as impulse or specific impluse.

If we have a constant impulse (thrust force) and the mass decreases the velocity (acceleration) increases. For much of the trip to the moon the Apollo spacecraft consisted of the SM, CM, LEM and the J-2 third stage. Much more mass than the returning craft (SM and CM only). Surely the thrust was different, but I'm guessing the ratio still gave the return trip configuration a higher V.

Don't confuse mass with weight. Mass is mass and doesn't change in different gravity fields, Weight is the the measurement of gravity's affect on a mass. A 80 km/hr fast ball with a mass of 1 kg will exert the same force on a catchers glove in space as it will in the Bronx even though it will "weigh" almost nothing in space.



[edit on 6/28/2007 by darkbluesky]

Originally posted by nescafe8572
I have to say that I don`t believe they went there in the first place.

Why.

NASA are currently developing the next trip to the moon and will take around 20yrs to put everything needed in place.

Why?

Can`t they just redevelop the original tech with obvious 21 centurary technology

Because
1. Throughout the 1960's NASA spent A LOT more money -- nearly twice as much -- on the Moon mission (in 2007 dollars) than they are now.

2. That was just about the single goal of NASA in the 1960's-- get a man to the Moon. Today NASA has many goals and various missions to concentrate on (unmanned Mars exploration, for insatnce).

3. NASA's mission in the 1960's was to get a Man to the Moon...That's it...not much more than that. This new Moon project (which will hopefully only take 15 years, not 20 as you mentioned) will be all about getting to the Moon AND STAYING THERE. This project is all about long-term missions which will eventually set up permanent bases on the Moon which will serve as a launching point (figuratively and maybe literally) for manned missions to Mars. They plan on doing the kind of science and human habitat research on the Moon which will help us on our quest to set up permanent bases on Mars. In a nutshell, it's taking longer because they are building the infrastructure required to do it right this time instead of some "let's plant a flag and go home" type of mission.

[edit on 28-6-2007 by Soylent Green Is People]

Think about it this way. When they start, with the rocket on the ground, their velocity relative to Earth is 0. As they go to the moon, they build up a lot of velocity relative to the Earth. Even while they're orbiting the Moon, relative to the Earth they're going very fast. So they've already got all that velocity behind them to bring them back to the Earth, so of course the trip is going to be shorter.

In Earth-based terms, think of a car sitting at a standstill, and then accelerating in a straight line for a quarter mile. Let's say that takes 15 seconds. Now consider a car that's driving in a circle at 30mph, and suddenly it takes off in a straight line for a quarter mile. That takes 10 seconds, because the car was already going 30mph when it started the trip.