Which factor is NOT considered when selecting a launch window?

When selecting a launch window for a spacecraft, several critical factors are taken into account to ensure a successful mission. Among these, the age of the spacecraft is not a primary consideration.

Weather conditions are vital, as adverse weather can impede a launch or affect the vehicle's performance during ascent. Orbital alignments are equally important, especially for missions aimed at rendezvousing with other celestial bodies or satellites; launches need to occur when the required trajectories and conditions are optimal. Mission objectives guide decisions related to timing, as specific celestial events or target positions may dictate the ideal launch timeframe.

In contrast, the age of the spacecraft does not impact the timing of the launch window. Although the spacecraft's operational status and overall health are critical for its performance, its age is not a deciding factor in determining the window for launching. Instead, more immediate technical considerations, such as systems readiness and potential issues arising from aging components, play a role in the overall mission planning but do not specifically define the launch window.