Science at Parramatta High

5 second movie of Jupiter

This movie was taken on 7/11/99, through a 90mm (1450mm focal length) Maksutov-Cassegrain telescope.
It was recorded on a webcam mounted at the prime focus.
Originally a very large .avi movie, it has been converted to a reasonable-sized gif.
The shimmering is principally a function of atmospherics ("seeing").
The upwards movement is the equatorial motion of the planet.
(No equatorial tracking was used at the telescope.)

Processed composite frame At left is a composite image taken on 20/9/99. It is composed of one image which was exposed for the disk of Jupiter (and didn't resolve the moons) plus another which shows the moons, but washed out the disk. The two were image processed (contrast and brightness), then combined to produce the result shown here.
The moons (left to right) Ganymede, Io and Europa can be seen here. Callisto is out of the frame, way to the left.
Moon occulting Jupiter At the time these photos were taken, the angular diameter of Jupiter's disk was 47.8 arcseconds.
Jupiter's brightness was magnitude -2.8 (that's bright!)
By way of comparison, the moon was 30 min 2 seconds wide. That's 1802 arcseconds, or about 38 times the diameter of Jupiter.The photo at right (sadly, not mine) illustrates this relationship. It shows Jupiter just about to pass behind (be occulted by) the moon.

STOP PRESS. (10 days later) The photos at right were taken with the school's Mavica digital camera, using the eyepiece projection method.
The two moons were touched up just a little (honest!)

(5 weeks later) The photo at right was taken with the webcam (just like the ones at the top of the page) but with a 2x teleconverter fitted.

The picture at far right is Jupiter's appearance as predicted by a PC-based graphical ephemeris.

November 7 1999

Return to near occultations or lunar eclipse or Saturn or
go on to the moon - same magnification.
Information about the telescope and camera used for these photos.
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