Comments on: Dart changed the orbit of the Didymos/Dimorphos binary asteroids around the Sun https://behindtheblack.com/behind-the-black/points-of-information/dart-changed-the-orbit-of-the-didymos-dimorphos-binary-asteroids-around-the-sun/ Mon, 09 Mar 2026 23:38:59 +0000 hourly 1 https://wordpress.org/?v=6.9.4 By: Robert Zimmerman https://behindtheblack.com/behind-the-black/points-of-information/dart-changed-the-orbit-of-the-didymos-dimorphos-binary-asteroids-around-the-sun/#comment-1629614 Mon, 09 Mar 2026 23:38:41 +0000 https://behindtheblack.com/?p=122098#comment-1629614 In reply to Edward.

Edward: Thank you. I stand corrected. I will fix the post.

]]> By: Edward https://behindtheblack.com/behind-the-black/points-of-information/dart-changed-the-orbit-of-the-didymos-dimorphos-binary-asteroids-around-the-sun/#comment-1629613 Mon, 09 Mar 2026 23:37:05 +0000 https://behindtheblack.com/?p=122098#comment-1629613 Robert,
“To be precise, the orbital speed was slowed 1.7 inches per hour, which while tiny would mean its solar orbit is now slightly lengthened.”

Ah, the orbital-mechanics trap! When you slow down, you speed up. By slowing the speed by 1.7 inches per hour, two things happen: One, the orbital circumference becomes ever so slightly smaller, and two, the speed at perihelion is ever so slightly faster, increasing ever so slightly the average speed around the Sun. The result is that the period of the orbit becomes ever so slightly shorter, not lengthened.

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