by rSherwood » Sun Jan 21, 2024 8:47 pm
At the "boostback burn ends" point, the boosters are still at high elevation. Booster separation occurred shortly after the rocket entered the picture frame at upper left when it was above most of the atmosphere. The launch pad was way beyond the top left corner of the picture; it could have only been shown with an extremely wide-angle lens. After the boostback burn ended, the boosters were in free-fall, unseen as they traveled down, off the top of the image back toward the launch pad. They reentered the atmosphere at supersonic speed, and a second burn, the reentry burn, reduced their velocity. After additional free-fall, a third burn slowed the boosters to landing velocity. The APOD image shown neither of these later two burns.
At the "boostback burn ends" point, the boosters are still at high elevation. Booster separation occurred shortly after the rocket entered the picture frame at upper left when it was above most of the atmosphere. The launch pad was way beyond the top left corner of the picture; it could have only been shown with an extremely wide-angle lens. After the boostback burn ended, the boosters were in free-fall, unseen as they traveled down, off the top of the image back toward the launch pad. They reentered the atmosphere at supersonic speed, and a second burn, the reentry burn, reduced their velocity. After additional free-fall, a third burn slowed the boosters to landing velocity. The APOD image shown neither of these later two burns.