Planet Jupiter, before cometary impact
About this image
This frame is of the planet Jupiter taken in July 1994, before the planet's collision with comet Shoemaker-Levy 9 (it may be interesting to compare this image with an image taken after the the impact of SL 9 in later July).
This picture was obtained on July 13th under excellent observing conditions. It is somewhat rare to observe an object as bright as Jupiter with a 4-meter-class telescope like the WIYN, but the WIYN imager is able to open its shutter for only one tenth of a second. Other telescopes on Kitt Peak have a minimum exposure time of one second, which would have resulted in a completely saturated image. It is fortunate that such a short exposure was possible, not only to avoid saturation, but also because the telescope at that time was still being built and was not capable of tracking (i.e., following an object across the sky as the Earth rotates under us).
Although this does not match the superb resolution to which we have all become accustomed for planetary images taken by satellites and by the Hubble Space Telescope, this is one of the finest ground-based images of Jupiter, with an estimated image quality ("seeing") of better than 0.7 arc seconds.
This image has been "flattened", so that it has about the same brightness all the way across the planet's disk: normally, pictures of planets are much dimmer near the edges (due to physics, of course, not due to bad picture taking).
Further information about the comet/planet "event" is available via the NOAO home page.
Minimum credit line: WIYN/NOAO/NSF
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