Doing Calcs and Knowing Where in the Orbit You Are.

[davidpsummers]

I've trying to do a solar orbit satellite contract and I would like to do better than just eyeballing where the maneuver nodes go.

However, the target orbit can't be designated as a target. The contract gives you orbit parameters. However, to use them you need to know where on your orbit your vessel is with respect to the reference direction. I mean, you know that the angle for the burn you want is 132 degrees with respect to the reference direction, but unless you know where you ship is with respect to the reference direction, that doesn't help you.

How can you know your current angle with respect to the reference direction?

[Rhomphaia]

Mods, such as Kerbal Engineer Redux or MechJeb.

[davidpsummers]

Mods, such as Kerbal Engineer Redux or MechJeb.

I use Kerbal Engineer and I couldn't find it. What the term?

[GoSlash27]

I've trying to do a solar orbit satellite contract and I would like to do better than just eyeballing where the maneuver nodes go.

However, the target orbit can't be designated as a target. The contract gives you orbit parameters. However, to use them you need to know where on your orbit your vessel is with respect to the reference direction. I mean, you know that the angle for the burn you want is 132 degrees with respect to the reference direction, but unless you know where you ship is with respect to the reference direction, that doesn't help you.

How can you know your current angle with respect to the reference direction?

davidpsummers,

That sort of thing is normally done with time. If you know what time you pass over KSC and your period, then you can work out your longitude simply by the time of day.

But in your case, you'd have to know what zero is for the argument of right ascension. I don't know where that is for the sun. I'd guess it's on Kerbin's radial at the start of the year.

If that's the case, then you'd know by the calendar, same way we spitball transfer windows.

As for burn angles, your nav ball is useless for a reference in the solar ecliptic until you're out of Kerbin's SoI, so I've got nuthin' for you there.

Best,

-Slashy

Edited July 19, 2015 by GoSlash27

[davidpsummers]

davidpsummers,

That sort of thing is normally done with time. If you know what time you pass over KSC and your period, then you can work out your longitude simply by the time of day.

But in your case, you'd have to know what zero is for the argument of right ascension. I don't know where that is for the sun. I'd guess it's on Kerbin's radial at the start of the year.

If that's the case, then you'd know by the calendar, same way we spitball transfer windows.

As for burn angles, your nav ball is useless for a reference in the solar ecliptic until you're out of Kerbin's SoI, so I've got nuthin' for you there.

Yeah, for this problem I need to know the angle to the reference direction for the sun.

I take it for Kerbin, the reference directly is the location of KSP at some time (presumably Year zero).