Samples of my work

All images on this page are are protected by copyrights held by me and/or institutions I have worked with. Do not use or reproduce them without permission.

The ansae of the Io plasma torus, with Jupiter. [Click on the picture for a larger version.] These images, taken at the McMath-Pierce solar telescope at Kitt Peak, are from an ongoing imaging program: a custom-built instrument simultaneously images both ansae (sides) of the torus in singly ionized sulfur, together an image of Jupiter for improved spatial and intensity calibration. You can read more about this program in my 1999 AAS, 2000 AGU, and 2000 DPS meeting presentations.

Hydrogen and oxygen emission near Io. This is a composite of two pictures of Io acquired in the far ultraviolet with the Space Telescope Imaging Spectrograph: netural oxygen is shown in red and hydrogen in green. (The blue circle marks Io's limb.) The oxygen emission (and some similar-looking neutral sulfur emission) comes from neutral gas near Io, whereas most of the hydrogen emission appears to be reflected sunlight. For more info, check out my article in Science.

[S II] 6731Å emission from the east ansa of the Io plamsa torus on December 3, 1988, at 6:36 UT (from my dissertation). The part inside the blue circle is the actual image I got through the telescope (the McMath-Pierce solar telescope at Kitt Peak), consisting of light given off by ionized sulfur; the positions of Jupiter (red circle), Io (yellow dot), and Io's orbit (yellow ellipse) were calculated and added into the image later. The plasma, being electrically charged, is bound to Jupiter's magnetic field, which, like the Earth's, is not quite aligned with its spin; this is why the torus does not "line up" with Io's orbit. A version of this image is available for use as wallpaper here.