NASA Astronomy Picture of the Day Collection

Jupiter's Ring Halo

Why do small particles hover around Jupiter's rings? These particles form a previously unknown ring halo [ http://galileo.ivv.…], recently discovered by the robot spacecraft Galileo [ http://galileo.ivv.…] currently orbiting Jupiter [ http://www.seds.org…]. Galileo obtained this image when on the far side of Jupiter - from this orientation scattered sunlight [ http://www.gla.ac.u…] makes the halo ring [ http://galileo.ivv.…] visible. The amount of scattering indicates that halo particles are very small - perhaps 100 times smaller than the width of a human hair. Particles this small are believed to survive only for years, and so must somehow be replenished to Jupiter's ancient ring system [ http://antwrp.gsfc.…]. One possible explanation for this unusual halo is that electromagnetic fields [ http://www.ch.ic.ac…] around Jupiter [ http://antwrp.gsfc.…] gently push small charged particles out of the ring plane. This false color image [ http://galileo.ivv.…] has been artificially stretched in the vertical direction to highlight the ring halo.

Galileo Project, JPL, NASA [ http://www.nasa.gov/]

Jupiter

Callisto

Goddard Space Flight Center (GSFC)

Jet Propulsion Laboratory (JPL)

Galileo

Jupiter

Callisto

http://antwrp.gsfc.…

SPD-APOD-ap970807