# Is the fuel burn for a satellite launch affected by the position of the moon relative to the launch site?

The gross mass of a satellite rocket is tiny compared to that of Earth, and Luna. Between them, however, the two bodies set up tides in bodies of water which itself is again considerable mass.

At the point of launch a satellite rocket might not be affected by the Moon's gravitation attraction. As it goes higher/ more distant from earth/closer to escape/ target orbit do it's fuel burn statistics change depending upon the position of the moon vis-a-vis launch location/payload release location?

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Let us perform an analysis. Satellites normally don't go any closer to the Moon than geosynchronous orbit - about $42000~km$ in radius. Let's take a $17000~kg$ satellite nearing this altitude and say that the Moon is directly overhead. Then, on average the satellite would be $342000~km$ from the center of gravity of the Moon, which would mean it experiences a net force due to the Moon of around $6N$. This means an acceleration of $3.5*10^{-4} m/s^2$ towards the Moon. Again, this means that in the course of an hour, the Moon could add a maximum of around $1.3 m/s$ to the satellite's velocity. Given that a satellite at that orbit has a velocity around $3km/s$ and that lower satellites have faster speeds, it is safe to say that the Moon does not contribute in any significant way to changing the velocity during the launch/orbital insertion phases and as such, does not change the fuel statistics of launching a satellite.