Community > Forum > Technology & Science > Orbital Mechanics

Orbital Mechanics

Posted by: campbelp2002 - Thu Dec 23, 2004 7:49 pm
Post new topic Reply to topic
 [ 160 posts ] 
Go to page Previous  1 ... 4, 5, 6, 7, 8, 9, 10, 11  Next
Orbital Mechanics 

Could an object spiral into the Sun?
Of course! 64%  64%  [ 16 ]
No way! 28%  28%  [ 7 ]
I used to think so, but now I don't. 0%  0%  [ 0 ]
I didn't think so before, but now I do. 8%  8%  [ 2 ]
Total votes : 25

Orbital Mechanics 
Author Message
Moon Mission Member
Moon Mission Member
User avatar
Joined: Tue Oct 05, 2004 5:38 pm
Posts: 1361
Location: Austin, Texas
Post    Posted on: Fri Jan 21, 2005 3:12 pm
Ekkehard Augustin wrote:
The special situation I have in mind already is well defined

Please define it for me now, so I can use my own calculations to get to the same situation.

(EDIT) I have made additional improvements to the Java simulator. It now has the capability to simulate any thrust continuously for any duration you need.
http://home.austin.rr.com/campbelp/orbit.html
And please let me know how it performs on your computer. I am still trying to find out why it runs so slowly on some computers.


Back to top
Profile WWW
Moderator
Moderator
avatar
Joined: Thu Jun 03, 2004 11:23 am
Posts: 3745
Location: Hamburg, Germany
Post    Posted on: Sun Jan 23, 2005 4:21 pm
Peter,

previous to my comment to your post an additional explanation concerning my steps.

At or before the beginning of a step I look for special goals to be achieved by and during that step that make sense. The sense could be mathematical - helpful for my calculations and insights etc. - , physical, economical, regarding safety and else more perhaps. Each step provides a special milestone I will list when I have ready the step and corrected all errors detected.

I want to keep my steps for these reasons - and I want to keep the order of all steps including definitions, numbers etc AND SPECIAL SITUATIONS.

I do that because without any order the danger of becoming puzzled arises.

The special situation I have been speaking of and the definition of you want to know NOW instaed of waiting for it is that simple that you can detect it yourself easyly if you think about the goal of the mission I'm calculating. When might be the optimal situation to release the package and to decelerate and turn the vehicle?



Dipl.-Volkswirt (bdvb) Augustin (Political Economist)


Back to top
Profile
Moon Mission Member
Moon Mission Member
User avatar
Joined: Tue Oct 05, 2004 5:38 pm
Posts: 1361
Location: Austin, Texas
Post    Posted on: Sun Jan 23, 2005 10:08 pm
Ekkehard Augustin wrote:
When might be the optimal situation to release the package and to decelerate and turn the vehicle?

You don't know? You are just guessing at a speed and direction and sending your space craft that way and hoping that something will look good after some unknown time? And you cannot define clearly how you will know when it looks good, you only state that when you see it, you will recognize it? And after all these weeks you have no result from all your calculations, during which time I have written and posted an Excel program and a Java program, successfully calculated dozens of different orbits and posted the results, allowed you to use these tools to calculate your own orbits and explained in great and clear detail how all calculations work, all of which you have rejected.
You obviously don't know what you are doing.
I have stated many times, and proven it mathematically, that if you decelerate by 27 km/s from Earth's orbital velocity of 29.8 km/s, drop the package and then accelerate 27 km/s in the other direction to return to Earth, the object will hit the Sun. There are other maneuvers that could hit the Sun but they all require MORE acceleration.


Back to top
Profile WWW
Moderator
Moderator
avatar
Joined: Thu Jun 03, 2004 11:23 am
Posts: 3745
Location: Hamburg, Germany
Post    Posted on: Mon Jan 24, 2005 8:17 am
Peter,

you took my question "When might be the optimal situation to release the package and to decelerate and turn the vehicle?" from the wrong side (you are interpreting me).

I know the answer very well and I the vehicle is on its way to the point where this situation will be the actual situiation.

I have put the question to you as the answer to your question for the definition of the "special situation" - please think yourself what the answer to the question may be. YOU don't know - that's the reason why you were asking me. I MYSELF know very well. My posts in this thread and in the thread about the disposal of radioactive materials contain all informations you need to identify what a situation I have in mind calling it "optimal" or "special".

Please think about the question and when you find an answer ask me wether it was that answer what I have in mind.

I CAN define but I DON'T WANT to do it currently. I'm NOT guessing but experimenting and analyzing and playing.

My calculation will go on when I have time for them again - which by chance will be this week. I have nearly ready my repairs and savings of data after a sudden HDD-drive-damage. And this discussion here has been requiring time I'm missing to continue my calculations and their correction.

I don't reject your concept of thinking and calculation but I have started my own as you know and want to continue with them now. May be that we both at the end come to the same result by different ways - would be a good success.



Dipl.-Volkswirt (bdvb) Augustin (Political Economist)


Back to top
Profile
Moon Mission Member
Moon Mission Member
User avatar
Joined: Tue Oct 05, 2004 5:38 pm
Posts: 1361
Location: Austin, Texas
Post    Posted on: Mon Jan 24, 2005 1:32 pm
Ekkehard Augustin wrote:
please think yourself what the answer to the question may be. YOU don't know

Yes I do. My “special situation” is
Peter Campbell wrote:
decelerate by 27 km/s from Earth's orbital velocity of 29.8 km/s, drop the package and then accelerate 27 km/s in the other direction to return to Earth

You have only said
Ekkehard Augustin wrote:
I MYSELF know very well

But you have given no numbers. No exact definition. And you do not agree with my numbers. You do not agree with my exact definition. My definition which is posted here and now. 27 km/s slower than Earth along Earth’s orbit. If you already have a different situation in mind, post it here and now. If you can’t define it clearly here and now then stop saying you “know very well”.


Back to top
Profile WWW
Moderator
Moderator
avatar
Joined: Thu Jun 03, 2004 11:23 am
Posts: 3745
Location: Hamburg, Germany
Post    Posted on: Mon Jan 24, 2005 2:05 pm
I have a quite different situation in mind - and you already have all informations required to find out yourself which situation it is and what are the special properties of that situation.

The definition of YOUR special situation has its problems.

1. How long would you decelerate?
2. What distance of Earth will be reached then?
3. What is the gravitational acceleration at the point where the package is dropped? This third has its special problem. Assume the gravitational acceleration is 0.000001 km/s°2 and multiply this number by the number of seconds per year - then the package will have fallen 31,55855 km after one year. It is still nearly as close to Earth as it was at the time when it has been dropped. Assume that the gravitational acceleration is ten times higher - the package will have fallen 315,5855 km after one year then. That too is still nearly as close to Earth as at the time of dropping. The correct number will be somwhere between these numbers or less than the first number. For this reason I'm going the other way which is providing a special situation.
4. Does the vehicle go back along Earth's orbit only? Then the package will be much closer to Earth after one year than calculated in the examples under 3. It would collide to Earth I suppose.



Dipl.-Volkswirt (bdvb) Augustin (Political Economist)


Back to top
Profile
Moon Mission Member
Moon Mission Member
User avatar
Joined: Tue Oct 05, 2004 5:38 pm
Posts: 1361
Location: Austin, Texas
Post    Posted on: Mon Jan 24, 2005 2:28 pm
Ekkehard Augustin wrote:
you already have all informations required to find out yourself

So you are unable to restate it here. In other words you don’t know either. I will restate mine again. 27 km/s slower than Earth and in the same direction as Earth’s orbit around the Sun.



Ekkehard Augustin wrote:
1. How long would you decelerate?

It does not matter. For example, I could decelerate at 1g for 2700 seconds. Or I could decelerate at 1/10g for 27000 seconds.

Ekkehard Augustin wrote:
2. What distance of Earth will be reached then?

This also does not matter. I assume far enough so that Earth’s gravity can be ignored, because I am not calculating the effects of Earth’s gravity. And neither are you.

Ekkehard Augustin wrote:
3. What is the gravitational acceleration at the point where the package is dropped?

0.000005897 km/s^2. But this increases to 0.00000677after the object has moved to 1/10 of the way to the Sun. And in increases to .00059 km/s^2 after the object has moved 9/10 of the way to the Sun. And it has increased to 0.273 km/s^2 just before it hits the Sun. You can’t just look at the gravity where you are now. You have to integrate the acceleration over the entire path. It would take about 68 days to reach the Sun. You can easily do this same calculation in a few seconds with the http://home.austin.rr.com/campbelp/orbit.html if your computer runs it fast enough. You still have not said how well this applet runs on your computer.


Back to top
Profile WWW
Moderator
Moderator
avatar
Joined: Thu Jun 03, 2004 11:23 am
Posts: 3745
Location: Hamburg, Germany
Post    Posted on: Mon Jan 24, 2005 2:54 pm
I have posted several numbers going into my calculations during the other thread. And we both know waht the purpose is - to throw a package into the sun.

The numbers and the purpose are sufficient information to find out the properties of the special situation yourself.

That Irefuse to staet the properties here doesn't necessaryly or logically mean that I am unable to state them here nor does that mean that I don't know either. What you wrote simply is an interpretation and it's a kind of interpretation often used by people to get statements or information from someone who refuses to give the statements or informations - a well-known political trick. :lol: I simply don't want to do the thinking for you - I wnat you to think youself to find out. If I would state it here I quickly will have another discussion keeping me from my calculations, data repairs and data reconstructions and I don't want to be kept from my calculations. The special situation is a milestone of one of my steps and relevant for achieving the purpose successfully. When my vehicle reaches the point where the special situation is valid I will say that explicitly.

What I said in my last answer didn't have anything to do with Earth's gravity - it has to do with adding up or integrating the gravitational acceleration. I didn't integrate in that previous post but I'm adding up during my own calculations - and it is still less than the number you are stating here after the first 1,300,000 seconds.

If the acceleration by 0.000005897 km/s^2 is the acceleration at Earth's distance or close to Earth's distance from sun then the number is too large by 10 - compared to the numbers my sources are stating. These sources I have listed in a thread under "The Spaceflight Cafe".



Dipl.-Volkswirt (bdvb) Augustin (Political Economist)


Back to top
Profile
Moon Mission Member
Moon Mission Member
User avatar
Joined: Tue Oct 05, 2004 5:38 pm
Posts: 1361
Location: Austin, Texas
Post    Posted on: Mon Jan 24, 2005 3:30 pm
Ekkehard Augustin wrote:
often used by people to get statements or information from someone who refuses to give the statements

Exactly. The politician does not want to give a direct answer to a simple question because the true answer would be too embarrassing. You are doing just that. You are playing the politician, which is only to be expected since you are the Political Economist.

Calculating the path of the powered space craft to the point of release is useless unless you have already calculated the path of the package from the point of release to the Sun and confirmed that it will actually hit the sun. You have skipped that necessary first step!

Ekkehard Augustin wrote:
If the acceleration by 0.000005897 km/s^2 is the acceleration at Earth's distance or close to Earth's distance from sun then the number is too large by 10

That number is correct.
Universal gravitational constant G = 6.6742 X 10^11 m^3 kg^-1 s^-2
Or in different units G = 6.6742 X 10^-20 km^3 kg^-1 s^-2
Mass of Sun M = 1.989 × 10^30 kg
Distance to Sun R = 150,000,000 km.
GM/R^2 = 6.6742 × 10^-20 * 1.989 10^30 / 150,000,000^2 = 0.000005899
So I may be off in the 9th decimal place, but not off by 10 times.


Back to top
Profile WWW
Moon Mission Member
Moon Mission Member
User avatar
Joined: Tue Jul 15, 2003 8:46 pm
Posts: 1215
Location: Kapellen, Antwerp, Belgium, Europe, Planet Earth, the Milky Way Galaxy
Post    Posted on: Mon Jan 24, 2005 3:50 pm
Maybe it's time to end this discussion ;)

I know how physics works... as game programmer... I even wrote my own physics engine..

I'm not willing to read all your posts... so I'll "guess" about the question, if it's wrong the question please fix me, so I can give a right answer.

The question:
Can an object "spiral" with vector change of atleast 360 degrees, back to same vector direction before coliding with the sun ?

Answer:
Yes and no:

No: if you're pushing an object from earth to the sun, it will collide with the sun BEFORE it can change it's vector 180 degrees, OR it will bend it's vector and go back into space with high speed.
It will NOT go into an orbit with each time a small altitude change.

yes: if the object is "powered" into a sun orbit, and lower it "manually", but you would be just colliding with the sun in the end, OR if not mannaged manually, there is a large chance it will also fly into deep space to be never seen again.

With other words, it's only possible if human brains are putting energy into it, else it can only be a direct "collision".

_________________
Heavier-than-air flying machines are impossible. - Lord Kelvin, 1892


Back to top
Profile WWW
Moon Mission Member
Moon Mission Member
User avatar
Joined: Tue Oct 05, 2004 5:38 pm
Posts: 1361
Location: Austin, Texas
Post    Posted on: Mon Jan 24, 2005 4:12 pm
You are correct. The poll shows, so far, that 6 out of 16 people agree with you. Would you prefer that Ekkehard and I continue this with private messages?

Also, how does the Java applet run on your computer? I really hate Java because it is not as portable as it claims. But I still don't know how much success other people have had running it on their computers.
http://home.austin.rr.com/campbelp/orbit.html


Last edited by campbelp2002 on Mon Jan 24, 2005 4:22 pm, edited 1 time in total.



Back to top
Profile WWW
Moon Mission Member
Moon Mission Member
User avatar
Joined: Tue Jul 15, 2003 8:46 pm
Posts: 1215
Location: Kapellen, Antwerp, Belgium, Europe, Planet Earth, the Milky Way Galaxy
Post    Posted on: Mon Jan 24, 2005 4:21 pm
campbelp2002 wrote:
You are correct. The pole shows, so far, that 6 out of 16 people agree with you. Would you prefer that Ekkehard and I continue this with private messages?

Also, how does the Java applet run on your computer? I really hate Java because it is not as portable as it claims. But I still don't know how much success other people have had running it on their computers.
http://home.austin.rr.com/campbelp/orbit.html

No need for private discussions, I want to know when Ekkehard Augustin understands the math ;)

About the java applet, it seems to run normaly, but havn't tested it in detail.

_________________
Heavier-than-air flying machines are impossible. - Lord Kelvin, 1892


Back to top
Profile WWW
Moon Mission Member
Moon Mission Member
User avatar
Joined: Tue Oct 05, 2004 5:38 pm
Posts: 1361
Location: Austin, Texas
Post    Posted on: Mon Jan 24, 2005 4:26 pm
I really want Ekkehard to understand too, but I am loosing hope.

The Java applet runs great on my Windows 2000 machine at work but horribly on my Windows 98 and XP machines at home. At home it is extremely slow and not all the numbers display. In particular the elapsed time, current speed and distance are frequently missing from the display.


Back to top
Profile WWW
Moderator
Moderator
avatar
Joined: Thu Jun 03, 2004 11:23 am
Posts: 3745
Location: Hamburg, Germany
Post    Posted on: Mon Jan 24, 2005 6:33 pm
Peter,

I checked my sources when I arrived at home two hours ago - sour number is NOT wrong by a factor of 10.

Concerning the special situation I give you one special and last hint - look for a Berak-Even-Point. There is one and I don't nedd a complete calculation of the path to define it - I do need the numbers already posted only.

My calculations don't have the purpose to prove something or to argue against YOUR calculations. They are simply a different way than yours and their purpose is to calculate the movements of a vehicle that is able to react to gravity by strong and crafty engines. It can operate freely. Compare the acceleration of 1 g the pulsed fusion engine is providing to the gravitational acceleration of 5.92 * 10^6 km/s at Earth's distance from sun.



Hello, Sigurd,

I agree that this discussion can and should be terminated.

If desired I will send my Excel-spreadsheet to each person interested in them. I too have no problem to post the formulars here that I#m using in the spreadsheet. But the numbers I#m calculating are too much to post them here - tens of thousands are ready.

As far as I could see during this thread and during the other thread I#m getting nearly the same results as Peter - except the consequences of using engines and the like. This may be due to firing them at other times and locations than Peter does in his own calculations.

The Break-Even-Point I'm speaking of above and that is a property of a special situation I this moment really don't want to post here - to slow down this discussion. I am a little bit tired of it.

The "spiral" is simply a raw description of a graphical shape I got a few years ago as the consequence of an error caused by wrong scaled vectors.

Now I will lock this thread.



Dipl.-Volkswirt (bdvb) Augustin (Political Economist)


Back to top
Profile
Moon Mission Member
Moon Mission Member
User avatar
Joined: Tue Jul 15, 2003 8:46 pm
Posts: 1215
Location: Kapellen, Antwerp, Belgium, Europe, Planet Earth, the Milky Way Galaxy
Post    Posted on: Mon Jan 24, 2005 7:10 pm
I don't think thread should be locked... (I unlocked it)... anyone who wants to add something.. should be free to do so...and it does NOT force anyone else to reply to it..
and personally, I think only Ekkehard Augustin and campbelp2002 reads it all...

_________________
Heavier-than-air flying machines are impossible. - Lord Kelvin, 1892


Back to top
Profile WWW
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 160 posts ] 
Go to page Previous  1 ... 4, 5, 6, 7, 8, 9, 10, 11  Next
 

Who is online 

Users browsing this forum: No registered users and 18 guests


cron
© 2014 The International Space Fellowship, developed by Gabitasoft Interactive. All Rights Reserved.  Privacy Policy | Terms of Use