A launch window is the period of time on a given day during which a rocket can lift off and still reach its intended orbit or trajectory. For some missions the window is instantaneous; for others it spans hours.
Windows are set by the geometry of the target orbit, the performance of the vehicle, the position of the launch site relative to the orbital plane, and constraints such as range safety and weather.
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Europa Clipper: Why Probing a Subsurface Ocean Changes Planetary Astrobiology Forever
Unlike Mars, which records the fossilized dry remnants of ancient water, Europa holds twice the liquid volume of all Earth's oceans combined beneath a 20-kilometer ice crust. This mission departs Earth not to find microbial life directly, but to confirm whether the thermodynamic conditions for life exist beneath an alien ice cap.
What Is a Static Fire and Why It Matters
A static fire holds a rocket down while its engines ignite at full thrust. It is the last major ground test before flight, and it regularly reshuffles the launch calendar.