Comet C/2002 C1 Ikeya-Zhang
The Morien Institute Skywatching Expeditions are simply that - skywatching. We have not used telescopes to date, simply because we are interested in seeing the sky in the way that ancient peoples did. Regretably this is not possible today for a number of reasons, some quite obvious and others not so immediately apparent. Sodium street lighting causes an amazing amount of 'light pollution' - something which is not noticed at all by city-dwellers until they take a trip out into the countryside at night and see the night-sky in all its natural beauty. After three or four successive clear nights the observer begins to appreciate the vastness of the universe, often for the first time, and the sporadic meteors that can be seen every night bring home the reality that it is a perpetually changing, living cosmos.
Every now and again a comet passes through our solar system on an orbit that takes it around the sun and then back again out into space. These 'periodic' comets are known to be a mixture of types ranging from 'dirty snowballs', because they are made up of a mixture of ices and dust, to 'icy rubble piles'. The ices are not all water-ice, there are a number of gasses in the composition of most comets, and the dust is not all dust either. Inside these dirty snowballs can be rocks of various sizes from a grain of sand to asteroid-sized chunks of metal and rock which can be many miles in diameter. They exist alongside sub-micron dust, which gets blown away from the comet by the solar wind as it approaches the sun and the ices begin to melt.
This out-gassing takes the form of a 'tail', and depending on the dust-gas ratio of the individual comet the tail can be either very tiny or really spectacular. C/2002 C1 Ikeya-Zhang is said by astronomers at Armagh Observatory in the north of Ireland to have to have "a fairly high gas-to-dust ratio, reducing the prominence of the developing dust tail". Even so, below are a selection of images showing the tail of Comet Ikeya-Zhang as it approaches our sun since its discovery on February 1st 2002 by Kaoru Ikeya of Shizuoka prefecture, Japan, and Daqing Zhang of Henan province, China, both of whom were working completely independently of each other on that night.
The image below shows the orbits of the planets in our solar system, and the orbit of Comet Ikeya-Zhang (C/2002 C1) as illustrated by Larry Koehn of Antioch, Tennessee on Gary Kronk's Cometography website where this image originates:
There are many more images of Comet Ikeya-Zhang available on the Internet. By clinking on the following dates you can see a wide variety of astro-photographs taken from a number of different locations on planet Earth on those dates. The archive of most of these images are the website of The Astronomer Magazine, where you can find images of comets from 1995 to the present day, and where the images typically are accompanied by details of the telescopes used, and usefully of the camera settings used to obtain the photographs.
follow the date sequence and watch the comet tail grow ...
March 1st | March 1st | March 1st | March 2nd | March 3rd | March 4th | March 5th | March 7th | March 7th
March 8th | March 8th | March 9th | March 10th | March 11th | March 23rd | March 26th | March 31st
April 3rd | April 6th | April 7th | April 8th
by clicking on the following link you can access a list of all the
Sky & Telescope Magazine |
Flandrau Science Centre |
Arcturus Observatory |
NASA Jet Propulsion Laboratory
the Morien Institute supports
please take a look at our Telescopes Store for a wide range of 'telescopes', 'binoculars', 'eyepieces', 'filters', 'tripods' and whatever 'accessories' you could possibly need ...
please take a look at our astronomy programs & night-sky software for PCs and our
The Morien Institute