Pick a rotation sense and scrub or play elapsed years to watch the thermal-lag hot spot push a spinning asteroid's orbit in or out, then read Bennu's real OSIRIS-REx-measured drift rate.
A spinning asteroid absorbs sunlight and re-emits it as heat with a delay, so the warmest surface point trails local noon instead of sitting under the Sun. That lag gives the re-emitted heat a net push: on a retrograde rotator like asteroid Bennu the push removes orbital energy and the orbit slowly shrinks; on a prograde rotator the same mechanism adds orbital energy and the orbit slowly grows.
Drag to orbit and scroll or pinch to zoom. For impulsive gravity-assist maneuvers see the Gravitational Slingshot 3D Explorer; for a tidal-disruption boundary see the Roche Limit 3D Explorer.
Yarkovsky Effect 3D Explorer
This browser explorer shows a spinning asteroid's thermal-lag hot spot driving its orbit in or out, then lets you compare that against asteroid Bennu's real OSIRIS-REx-measured drift rate.
The Yarkovsky effect is a non-gravitational, sunlight-powered orbit-shifting force. A rotating asteroid absorbs sunlight on its day side and re-emits it as heat after a thermal lag, so the warmest point trails local noon. That lagged re-emission carries a tiny recoil push - NASA JPL describes the thrust as "about the same as the weight of three grapes" - but compounded over years it measurably changes the orbit. Asteroid 101955 Bennu is a measured retrograde rotator: years of radar and optical astrometry, refined by OSIRIS-REx radio tracking, found a semimajor-axis drift of -284.6 +/- 1.5 meters per year (Chesley et al. 2014, Icarus), a shrinking orbit consistent with retrograde rotation, and a cumulative positional shift of about 160-185 km measured between 1999 and 2012. The Yarkovsky effect is the dominant non-gravitational force reshaping the orbits of asteroids roughly 10 meters to 10 kilometers across - much smaller or larger bodies are dominated by other effects.
- Pick a rotation sense: Retrograde (Bennu, measured) or Prograde (teaching mirror)
- Scrub or play elapsed years (0-100) to watch the orbit ring shrink or grow
- Read the cumulative drift readout alongside Bennu's real measured figures
- Compare with the gravitational-maneuver siblings
- Drag to orbit, scroll or pinch to zoom
- Runs fully in the browser with the vendored three.js engine - no account, no upload
| Figure | Value |
|---|---|
| Bennu semimajor-axis drift | -284.6 +/- 1.5 m/year (Chesley et al. 2014, JPL-refined post-OSIRIS-REx) |
| 1999-2012 measured shift | about 160-185 km |
| Thrust magnitude | "about the weight of three grapes" (NASA JPL) |
| Dominant size range | asteroids roughly 10 m to 10 km across |
Bennu's refined orbit - informed by this measured drift - puts its cumulative impact probability through the year 2300 at about 1-in-1750 (NASA JPL, post-OSIRIS-REx refinement). For impulsive gravity-assist maneuvers, open the Gravitational Slingshot 3D Explorer; for a tidal-disruption boundary, open the Roche Limit 3D Explorer.
Everything renders on your device with WebGL. The 3D engine loads once (about 0.7 MB) and is cached.
This is an educational approximation - the hot-spot lag angle, recoil arrow, and orbit-ring radius change are exaggerated for teaching, not a to-scale orbital-dynamics simulation. The Prograde option mirrors Bennu's real measured magnitude with the sign flipped to teach the general rule; it is not a second measured asteroid.
Frequently Asked Questions
What is the Yarkovsky effect?
A non-gravitational, sunlight-powered orbit-shifting force. A rotating asteroid re-emits absorbed sunlight as heat with a delay, so the warmest point trails local noon; that lagged re-emission carries a tiny recoil push that compounds over years.
How was it measured on asteroid Bennu?
Years of radar and optical astrometry, refined by OSIRIS-REx radio tracking, measured a semimajor-axis drift of -284.6 +/- 1.5 meters per year (Chesley et al. 2014, Icarus), plus a cumulative positional shift of about 160-185 km between 1999 and 2012.
Why does Bennu's orbit shrink instead of grow?
Bennu is a measured retrograde rotator. On a retrograde rotator the thermal-lag recoil push removes orbital energy, so the semimajor axis shrinks. On a prograde rotator the same mechanism adds orbital energy and the orbit grows instead.
Is the Prograde option a second real measured asteroid?
No. It mirrors Bennu's real measured magnitude with the sign flipped, to teach the general prograde/retrograde rule - it is a teaching mirror, not a second measured object.
How strong is the Yarkovsky thrust?
NASA JPL describes it as "about the same as the weight of three grapes" at any instant - vanishingly small, but large enough over years to decades to measurably shift an asteroid's orbit.
Which asteroids does it affect most?
The Yarkovsky effect is the dominant non-gravitational orbit-shifting force for asteroids roughly 10 meters to 10 kilometers across. Much smaller or much larger bodies are dominated by other effects.
How is this different from the gravitational-slingshot and Roche-limit pages?
Those pages teach gravitational mechanisms - an impulsive gravity-assist maneuver and a tidal-disruption boundary. This page is the only non-gravitational, sunlight-powered orbital-drift mechanism among the space visualizers on this site.
Is the on-screen drift real physics?
The direction of the effect (prograde grows, retrograde shrinks) and Bennu's cited rate are real. The hot-spot lag angle, recoil arrow, and orbit-ring radius change are exaggerated for teaching, not a to-scale orbital-dynamics simulation.