The Long Range Reconnaissance Imager (LORRI) on New Horizons has acquired
six global maps of Jupiter as the spacecraft approaches the giant planet
for a close encounter at the end of February. The high-resolution camera
acquired each of six observation "sets" as a series of
individual pictures taken one hour apart, covering a full 10-hour rotation
of Jupiter. The LORRI team at the Johns Hopkins University Applied Physics
Laboratory (APL) reduced the sets to form six individual maps in a simple
rectangular projection. These six maps were then combined to make the
movie.
The table below shows the dates and the ranges from Jupiter at which these
six sets of observations were acquired. Even for the latest set of images
taken January 21-22, from 60.5 million kilometers (37.6 million miles),
New Horizons was still farther from Jupiter than the average distance of
Mercury from the Sun. At that distance from Jupiter, a single LORRI
picture resolution element amounts to 300 kilometers (186 miles) on
Jupiter.
Many features seen in Jupiter's atmosphere are giant storm clouds. The
Little Red Spot, which LORRI will image close-up on February 27, is the
target-like feature located near 30 degrees South and 230 degrees West;
this storm is larger than the Earth. The even larger Great Red Spot is
seen near 20 degrees South and 320 degrees West. The counterclockwise
rotation of the clouds within the Great Red Spot can be seen. The westward
drift of the Great Red Spot is easily seen in the movie, as is the slower
drift, in the opposite direction, of the Little Red Spot. The storms of
Jupiter are not fixed in location relative to each other or relative to
any solid surface below, because Jupiter is a fluid planet without a solid
surface.
Also, dramatic changes are seen in the series of bright plume-like clouds
encircling the planet between 0 and 10 degrees North. Scientists believe
these result from an enormous atmospheric wave with rising air, rich in
ammonia that condenses to form the plume tails, and with falling air in
the dark areas just to the east of each plume.
The maps of Jupiter shown here do not include the polar regions, because
those regions are not well seen by LORRI from its vantage point high above
Jupiter's equatorial region. Shadows of Jupiter's moons (first of Io, then
of Ganymede) appear in two of the maps.
| Name |
Dates |
Range from Jupiter
[million km] |
Image resolution element
[km] |
| JobsATM1 |
Jan 8-9, 2007 |
81.2 |
402 |
| JobsATM2 |
Jan 9-10, 2007 |
79.9 |
396 |
| JobsATM3 |
Jan 14-15, 2007 |
71.9 |
356 |
| JobsATM4 |
Jan 15, 2007 |
70.5 |
349 |
| JobsATM5 |
Jan 20-21, 2007 |
61.8 |
306 |
| JobsATM6 |
Jan 21-22, 2007 |
60.5 |
300 |
