Defense Technology & Military Forum

Defense Technology & Military Forum (http://www.defencetalk.com/forums/)
-   Space & Defense Technology (http://www.defencetalk.com/forums/space-defense-technology/)
-   -   mars mission (http://www.defencetalk.com/forums/space-defense-technology/mars-mission-11820/)

crazydevil March 20th, 2012 12:54 AM

mars mission
 
what would be the minimum velocity increment required for a two impulse transfer from earth to mars about the sun??

StingrayOZ March 20th, 2012 03:10 PM

Quote:

Originally Posted by crazydevil (Post 241631)
what would be the minimum velocity increment required for a two impulse transfer from earth to mars about the sun??

Are you asking what would be the velocity for a simple earth - Mars journey? Unmanned, with no time pressure. You could do it over years, decades.

If you didn't have a two firing mission, then lowest energy would be the inter planetary transport network. I think the original NASA proposals had a possible Venus flyby so the direct route may not always be the best one to take.

crazydevil March 21st, 2012 01:45 AM

Quote:

Originally Posted by StingrayOZ (Post 241701)
Are you asking what would be the velocity for a simple earth - Mars journey? Unmanned, with no time pressure. You could do it over years, decades.

If you didn't have a two firing mission, then lowest energy would be the inter planetary transport network. I think the original NASA proposals had a possible Venus flyby so the direct route may not always be the best one to take.

yes , im talking about simple earth mars journey with no time pressure based on hoffmans transfer.Neglection the escape velocity of earth, we can assume the unmanned aircraft rotating in earths orbit around the sun.From there , with two velocity increments , it can be transferred to the orbit around mars.If so what would be those velocity increments.(im just doing some theoretical work on the same and would love to have your inputs )

StingrayOZ March 21st, 2012 03:34 PM

Its been ages since I studied orbital mechanics, I have a feeling its between 3-5.7km/s if you want a single shot from earth orbit. I see a bit of casual googling turns up loads of crap, I can see why your asking. I'll do a journal search at work and have a go at doing a napkin calculation.

PhysicsMan March 21st, 2012 06:44 PM

Quote:

Originally Posted by crazydevil (Post 241730)
yes , im talking about simple earth mars journey with no time pressure based on hoffmans transfer.Neglection the escape velocity of earth, we can assume the unmanned aircraft rotating in earths orbit around the sun.From there , with two velocity increments , it can be transferred to the orbit around mars.If so what would be those velocity increments.(im just doing some theoretical work on the same and would love to have your inputs )

Don't be lazy, just wiki "hoffman's transfer" and plug in the numbers, the formula is already there.

StingrayOZ March 21st, 2012 11:09 PM

Hmm is this a home work question? Lack of context and how it structured implies yes.

If you are after the velocity required with instant velocity (ie unrealistic) then it is a simple application of the Hohman (as the new texts call it) orbit formula which is really just the conservation of energy.

Remember your changing orbits around the sun.

It however isn't the ideal equation to calculate interplanetary travel because it doesn't take in effect all of the factors that realistically happen.

crazydevil March 22nd, 2012 02:23 AM

Quote:

Originally Posted by StingrayOZ (Post 241764)
Hmm is this a home work question? Lack of context and how it structured implies yes.

If you are after the velocity required with instant velocity (ie unrealistic) then it is a simple application of the Hohman (as the new texts call it) orbit formula which is really just the conservation of energy.

Remember your changing orbits around the sun.

It however isn't the ideal equation to calculate interplanetary travel because it doesn't take in effect all of the factors that realistically happen.

.Ive been reading a little bit about interplanetary orbital transfers in MIT opencourse materials and juz want wanted to calculate theoretically the velocity increments needed for the transfer.I did some vague calculations and got first velcoity increment from orbit of earth around the sun to elliptcal orbit around the sun as 2.9km/s and then to an orbit of mars around the sun as 2.6km/sec(talking into consideration only the conservation of energy).But couldnt find any source to verify my answers.Further i want to add practcality into this theoretical speed to arrive at final speed required and would be great if you guyz could help me out:)

Sandhi Yudha August 5th, 2012 11:44 PM

Oke boys, today Mars Science Laboratory will land on the surface of Mars. It will be about 2 hours from now.....cant wait until we receive the first data and pictures.....

For more info and updates:
Mars Science Laboratory

Sandhi Yudha August 6th, 2012 01:51 AM

Mars Science Laboratory just landed.
(more or less) live at CNN.com International - Breaking, World, Business, Sports, Entertainment and Video News

Belesari August 7th, 2012 06:28 PM

Quote:

Originally Posted by Sandhi Yudha (Post 249781)
Mars Science Laboratory just landed.
(more or less) live at CNN.com International - Breaking, World, Business, Sports, Entertainment and Video News

Its awesome aint it :)

The mission is for 2 year but if this one can stand up to the 5 years till the reactor runs out it would be awesome and kinda normal. The others were only supposed to last a few months.


All times are GMT -4. The time now is 09:31 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2003-2011 DefenceTalk.com. All Rights Reserved.