Combined ultraviolet- and visible-light images of Jupiter from NASA's Hubble Space Telescope were taken from February 17-21 in support of the New Horizons flyby of Jupiter on February 28.
The image segments in the boxes were obtained using Hubble's Advanced Camera for Surveys's ultraviolet camera. The ultraviolet images show auroral emissions that are always present in the polar regions of Jupiter. They are typically 10-100 times brighter than the northern lights seen on the Earth. The aurorae are produced when charged particles from the Sun become trapped in Jupiter's powerful magnetic field. They cause gasses to fluoresce high in Jupiter's atmosphere, near the planet's magnetic poles.
The equatorial regions of Jupiter in this photo were imaged in blue light on February 17, 2007 by the Wide Field Planetary Camera 2. This reveals cloud features in Jupiter's main atmosphere. In the ultraviolet views, the atmosphere looks more hazy because sunlight is reflected from higher in the atmosphere.
Hubble will continue to photograph Jupiter as well as its volcanically active moon, Io, over the next month as the New Horizons spacecraft flies past Jupiter. New Horizons is en route to Pluto, and made its closest approach to Jupiter on February 28, 2007.
Through combined remote imaging by Hubble and in situ measurements by New Horizons, the two missions will enhance each other scientifically, allowing scientists to learn more about the Jovian atmosphere, the aurorae, and the charged-particle environment of Jupiter and its interaction with the solar wind.
