Jupiter and Saturn
January 28, 1999
Low Res. (44 KB)
High Res. (191 KB)
Object Name: Jupiter and Saturn
Telescope: Subaru Telescope / Cassegrain Focus
Filter: B (Blue), V (visible), R (red)
Color: Blue (B), Green (V), Red (R)
Date: UT 1999 Jan 22
Exposure: 0.1 sec for each of the B, V, and R filters (with an ND filter),
except for the Saturn's B-band image taken with a 0.5 sec exposure
Field of View: 50 arcsec by 50 arcsec
Jupiter is the largest planet in the solar system with a diameter 11 times larger than that of the Earth. The image shows a complex feature of time variable bands, running parallel to the equator. The famous Great Red Spot is seen as an elliptical feature at the bottom right. Its diameter is twice that of the Earth. A black spot seen in the lower center is Ganymede, the third Jovian satellite. It looks dark because its reflectivity (albedo) is small compared to that of Jupiter. Ganymede's shadow is located beyond the surface of Jupiter when this observation was made. Images were taken at UT 5:34 for B, 5:39 for V, and 5:43 for R.
Saturn is the second largest planet in the solar system with a diameter 9 times larger than that of the Earth. The image shows time variable bands running parallel to the equator. These are similar to those seen on Jupiter, but are simpler in appearance. Saturn's rings have a diameter of 2.26 times larger than that of Saturn. The rings consist of three major ringlets, called the A, B, and C rings from outside to inside. The C ring is too faint to be seen in this image. The gap between the A and B rings is called Cassini's Division, after its discoverer. Images were taken at UT 6:22 for B, 6:27 for V, and 6:34 for R.