General Question Map MFD SOI

[Genius]

Is the SOI in the map MFD a true reflection of the planetary systems in Orbiter?

 

[Tommy]

Since the stock MapMFD doesn't show SOI, I'll assume you may be talking about the Map program in IMFD. It's more than reasonably accurate. The best way to know if you're in a body's SOI is to use the OrbitMFD. If the G number on the bottom is yellow or green, you are effectively in the body's SOI. If it's red, you're not.

 

[Genius]

Since the stock MapMFD doesn't show SOI, I'll assume you may be talking about the Map program in IMFD. It's more than reasonably accurate. The best way to know if you're in a body's SOI is to use the OrbitMFD. If the G number on the bottom is yellow or green, you are effectively in the body's SOI. If it's red, you're not.

My fault. I do mean Orbit MFD. Silly me.

 

[tblaxland]

By this definition of SOI:
http://en.wikipedia.org/wiki/Sphere_of_influence_(astrodynamics)

the G-indicator on OrbitMFD shows only 0.07 at the edge of Earth's SOI.

 

[Tommy]

By this definition of SOI:
http://en.wikipedia.org/wiki/Sphere_...(astrodynamics)

the G-indicator on OrbitMFD shows only 0.07 at the edge of Earth's SOI.

That is correct, you are within the Earth's SOI. However, you are also within the Sun's SOI, and sometimes also the Moon's SOI as all three can overlap.

The low G value shows that the Earth is a minor influence and your orbit is still mostly affected by another body (likely the Sun). A G value displayed in Yellow or Green indicate that the body is the primary object affecting your orbit. Many MFD's like IMFD's Base Approach program won't be accurate until the target body is the primary gravity source.

From the looks of things (Jarmonik would know for sure) the SOI circles displayed by IMFD's Map program reflect the border between primary and secondary sources, not the actual SOI