Comets are so popular. Here's a selection of "just-for-the-fun-of-it" pictures over the years.
I'll start with oldies but goodies. Here's a set of pictures done with the 61-cm Baker-Schmidt telescope at Vanderbilt University's Dyer Observatory near Nashville. Blue and yellow filters (denoted B and V) were used with O and D-class plates to isolate the ion and dust tails, respectively. The final picture, two months after perihelion, shows the splitting of the nucleus well.
|7 March V||7 March B||11 March V||28 March V||4 May V|
And speaking of famous, here are a few images of Comet Halley from 1986. We start with a wide-angle 35mm shot from La Silla when the comet was in front of the Milky Way, then zoom in for some views of the inner coma and nucleus made with the ESO 3.6m telescope, and a time sequence showing the nucleus almost occulting a star, as seen from the Cerro Tololo 1.5-meter telescope on 13 April 1986. The ESO closeups were taken through blue (B) and red (R) filters, with the telescope trackng at sidereal rate so that the comet's apparent motion in the intervening 118 seconds is obvious. These images cover regions 3.5 by 5.7 arcminutes.
The images in the appulse sequence were taken at 70-second intervals, as rapidly as the shutter and CCD readout would cycle (with 1-second exposures through a narrow-band filter). At closest appulse, the star's light passed about as close to the nucleus as Giotto did. I couldn't detect any absorption from photometry of the images to about the 1% level, which says that very little dust column density in a comet can be hazardous to your health.
|Wide-field view||7 April 1986, B||7 April 1986, R||Appulse animation|
And now up to the 1990s - three amazing examples. Gone but not forgotten, I have a couple of images of Shoemaker-Levy 9, from the Lowell Observatory 1.1m Hall telescope. One of them was taken only a few months after discovery. The second, six months later, was taken pretty low in the sky, but the comparison shows how the nuclei spread apart during its final orbit around Jupiter; the field size is 181", projecting to about 650,000 km at 5 AU. As is my usual practice, these use logarithmic intensity mapping to get more of the dynamic range visible at once.
|23 June 1993||13 December 1993|
And then we come to the two successive (northern) springtime H-comets. For Hale-Bopp, we offer a fine selection of scenic shots and closeups of the spectacular lawn-sprinkler shells around the coma. We have a series taken at the start of 4 consecutive nights, using the NASA IRTF 3-meter telescope at 2.25 microns. We tried to do this in daylight but never quite got organized enough to start the exposure until after sunset. This is the 75" field of the NSFCAM array; efforts to get a high-quality mosaic of multiple fields have been less than aesthetically pleasing so far. Dates are in local time (about 05:00 the following day UT). The rotation period was only a bit less than 0.5 day, so the rotation rate of the dust jet has aliased to look very slow.
|25 April 1997||26 April 1997||27 April 1997||28 April 1997|
For a wider view, here are some 50mm shots (scanned from Kodacolor 400 and 1000) from Mauna Kea during the same week:
|From Hale Pohaku||Above the IRTF||Over Keck II||With California Nebula|
And for a couple of parting shots closer to home, here are views from Tuscaloosa and environs. The dome contains the University of Alabama's 25-cm refractor, and that's Christopher at age 8 watching the comet from the balcony. The reflection is seen in the Black Warrior River as it bends around Moundville Archaeological Park about 30 km south of Tuscaloosa. And finally, we see Hale-Bopp with the crescent Moon and the Pleiades, from my very own front yard.
Last changes: November 1999