What is a launch window?
This article explains the concept of launch windows in space exploration, using China's delayed Chang’e 7 mission as a case study. It details how orbital mechanics and solar lighting requirements dictate when a spacecraft can be launched.
Why it matters
Understanding launch windows is essential for grasping the logistical and technical constraints of modern space exploration.
A: On August 24, China called off the launch of its Chang’e 7 mission to the moon’s south pole for the sake of “prudence, reliability and absolute mission success”. It will now have to wait until next year for another chance.
All space missions have specific launch windows — periods when the positions and motions of the satellite (on the rocket), the earth, and the target body are properly aligned. The moon orbits the earth once every 27.3 days, so launch windows to the moon open once a month. But if a mission has to go to the moon’s south pole region, the window changes.
Get smarter about the news
Sign up free for a feed built around what you actually care about, Dive Deeper research on any story, and the full text of every article.
Create free accountAlready have an account? Sign in