Although the prospects are much more favorable for using the station as a staging base for a further deployment of spacecraft that leave Earth's orbital environment—like the Webb telescope and missions to the moon or Mars—such outfitting would need to be done in the vacuum of space with the spacecraft docked to the station. The launch window to the moon, Mars or other points would occur far less often on the station than from the ground. For example, a lunar launch window from the station occurs approximately every 10 days. Mars is even more rare. From a rotating Earth, we can choose a launch window every day that aligns us into the plane of our trajectory to the moon or desired planet. The moon's 29-day orbit around the Earth helps to bring the ISS into alignment with it every 10 days, but Mars' relative motion is so small that we must wait for orbit precession alone, which gets us aligned roughly every 30 days or so.