Jupiter's Weather Forecast
One-hundred forty-seven (147) days before the Galileo Orbiter reaches Jupiter it will release an Atmospheric
Probe. Soon after release, the orbiter will burn its big engine for 5 minutes and end up on a path to Jupiter
that is slightly different from the path the Probe is taking. The Orbiter and Probe will reach Jupiter at the
same time (December 7, 1995) but will be out of communication until a 75 minute period called "Probe
Relay". During "Relay", the Probe will deploy a parachute and then descend about 150 km into the planet's
atmosphere. The Probe will send atmospheric data up to the Probe Relay Antenna and the data will be
recorded onboard the Orbiter. The data will be played back to Earth soon after the Jupiter encounter.
During the Probe's "pre-entry" phase, it will study the
energetic particle population in Jupiter's innermost
magnetosphere (Energetic Particle Instrument). During
descent, instruments on board the Probe will measure
temperature and pressure (Atmosphere Structure
Instrument), locate major cloud decks (Nephelometer
and Net Flux Radiometer) and analyze the chemistry of
atmospheric gases (Helium Abundance Detector and
Neutral Mass Spectrometer). The Probe will attempt to
detect lightning by looking for flashes of light and by
listening for the radio "static" they generate (Lightning
and Radio Emission Detector).
Photographs from space show how different weather is on Earth and Jupiter. On Earth, the cloud patterns are
mostly spiral-shaped storms. Jupiter's weather pattern is dominated by bands of clouds that are aligned with
its spin direction.
Several factors that contribute to the differences in weather on each planet are shown in the chart below.
Compare the two planets by filling in the rest of the blanks (use general descriptions, not quantitative values).
Does this chart help you understand WHY the weather on Earth and Jupiter look so different?
The weather report returned from the Probe may be like this:
Next page Contents
Last modified prior to September, 2000 by the Windows Team
The source of this material is Windows to the Universe, at http://windows2universe.org/ from the National Earth Science Teachers Association (NESTA). The Website was developed in part with the support of UCAR and NCAR, where it resided from 2000 - 2010. © 2010 National Earth Science Teachers Association. Windows to the Universe® is a registered trademark of NESTA. All Rights Reserved. Site policies and disclaimer.