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31

Addressing is the sun's mass and other quantities known well enough for this to be absolutely accurate? Well, the key to this is the vis-viva equation in your question. It's not actually important for us to know the mass of the Sun precisely, so long as we know the product $GM$ (another answer makes mention of this). And that product is, of course, the ...

24

The Vis-viva equation is $$v = \sqrt{ GM \left(\frac{2}{r} - \frac{1}{a} \right) },$$ The $GM$ product for the Sun is 1.327E+20 m^3/s^2. If 1 AU is 150E+09 meters, then when you are in a circular ($r=a$) Heliocentric orbit at Earth escape/capture point your velocity is 29.7 km/s. If you then change to an ellipse with aphelion still at 1 AU and ...

10

It's a "real number", a delta-v chart isn't really concerned with the realism of various missions. It's quite simply a table of velocity changes, how you would go about achieving these velocity changes is outside its scope. As to how to calculate it, the parts of the journey in space can be calculated like any other part of the diagram, using the patched ...

0

It would help if you showed your results at different steps. Then it would be less difficult to spot the error. End of January 2030 is about the right time for a Hohmann launch window to Jupiter (according to my arithmetic). But an Earth to Jupiter Hohmann is just short of a 1000 days. An 869 day trip would boost delta V. Regardless, I did a quick diagram ...

3

note: This is a very helpful extended comment that may be of use to the OP but it can't currently be posted as a comment until this user reaches 50 reputation points. Oh this is a fantastic question. It is common to fall into the following trap when making these types of calculations. Check carefully your reference frames. Celta V numbers are all relative,...

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