Geostationary Orbit around Venus?

[Lmoy]

I've been curious about this, but unable to find any information about it. Is it possible to put a satellite into a geostationary orbit around Venus? Or is the rotational period just too slow?

 

[asbjos]

I really doubt it is possible; the rotation is too slow (243 days, if I remember right) If you had an orbit around Venus with that roation period, you would be too far away from the sphere of influence. The closest thing would probably be a langrange point, where Venus would rotate something like 0,05 of an full day over a Venusian year from your lagrange point

 

[orb]

Calculated radius of a stationary orbit around Venus is 1536647 kilometers. Venusian SOI is 616000 km.

 

[RisingFury]

Even Earth satellites have trouble staying in a geostationary orbit because of the influence of the Moon and the Sun and they're only ~50 000km away. So putting a satellite at the edge of the SOI would already be no good, let alone over twice the SOI radius...

 

[T.Neo]

Suggestion #1; you could place yourself at the Venus-Sun L1 point. The angular diameter would be fairly small, the surface would still rotate (slowly) beneath you, and you'll have to do some stationkeeping to stay in place.

Suggestion #1.5; have satellites at the L1 and L2 points, monitoring the planet from both the day and night side, as well as satellites at the L4 and L5 points or in a suitably orbiting constellation to form a 'communication net' around the planet.

Suggestion #2; Place yourself in an orbit around Venus with the same period as the time it takes for the planet's upper cloud layers to rotate. Such an orbit should be within the planet's SOI and could enable better observations of weather phenomenon, or upper-atmosphere research stations/colonies.

Suggestion #3; Use a [ame="http://en.wikipedia.org/wiki/Statite"]statite[/ame] and hover above the planet using radiation pressure.

 

[Cras]

Even Earth satellites have trouble staying in a geostationary orbit because of the influence of the Moon and the Sun and they're only ~50 000km away.

eh, ~35,800 km

 

[orb]

eh, ~35,800 km

If you want to argue, the Earth's stationary orbit is 42164 km in radius.

You don't need to know the size of the planet to calculate it, only its rotation period and mass.

 

[Lmoy]

Ah, I see! Thanks for the information

Now what about Mercury?

 

[orb]

Now what about Mercury?

R = 242900 km, SOI =112000 km.

 

[Screamer7]

I hope this is not off topic, but I am curious.
What define a planet SOI.
I ask this because in Orbiter, orbit mfd the the SOI indicator is 1.0 if you are close to a planet or moon.
As you move father away in decrease to say .59.
If you are way out it decrease to 0.2 and eventually to 0.0 and turns red.
Is the SOI the boundary where it start to turn red at .49?
I also noticed when at IO at I am really hugging the moon at 10K the SOI stays low.
Is this because of Jupiter's immense gravitational field?

 

[orb]

What define a planet SOI.

http://en.wikipedia.org/wiki/Sphere_of_influence_(astrodynamics)

(While using the formula replace Sun with the major body of the system.)

 

[Rtyh-12]

I hope this is not off topic, but I am curious.
What define a planet SOI.

Wikipedia has a complicated formula: http://en.wikipedia.org/wiki/Sphere_of_influence_(astrodynamics). It depends, of course, by the Sun's influence as well as the mass: note how Neptune has a SOI larger than Jupiter's although it's (way) smaller, just because it's so far away from the Sun. Edit: :ninja:'d

I ask this because in Orbiter, orbit mfd the the SOI indicator is 1.0 if you are close to a planet or moon.
As you move father away in decrease to say .59.
If you are way out it decrease to 0.2 and eventually to 0.0 and turns red.

I'm not sure how Orbiter calculates that indicator, maybe someone better qualified can answer this? Anyway, it's important to remember that even inside the SOI, the orbit is still affected by other bodies.

I also noticed when at IO at I am really hugging the moon at 10K the SOI stays low.
Is this because of Jupiter's immense gravitational field?

It is indeed because of Jupiter. It's annoying, I know, since orbits aren't stable.

By the way, IMFD's map display shows (among others) the SOIs of objects. It's useful for, well, interplanetary travels :lol: