# What is the radius of a heliosynchronous orbit

What is the radius of a "heliosynchronous" orbit

## Homework Statement

The Sun rotates approximately every 26 days. What is the radius of a "heliosynchronous" orbit, that is an orbit that stays in the same spot of the sun.

## Homework Equations

r = ((GMT^2)/(4pi^2))^1/3

The suns mass is 1.99 X 10^30
Time = seconds
G = 6.67 X 10^-11

## The Attempt at a Solution

I'm not sure really except that I know how to find the radius but I'm not sure if its asking the same thing.

## Answers and Replies

Stonebridge

It's asking the distance of the orbit from the Sun. The criteria is that the centripetal force on the mass equals the Sun's gravitational force on it. The orbital speed at that distance is determined by the Sun's rotational period of "26 days".

As a note here, it might be worth looking up the difference between the Sun's sidereal rotation period, and its synodic rotational period, then looking at the value given in the question and asking a rather pertinent question...