In the early part of 1996 many were privileged to witness the close approach of a mass of material from the outermost reaches of the solar system. As it swept in along its multi-thousand year orbital path [see figure], heat from the sun stimulated the eruption of a far flung coma and the strewing of long, diaphanous dust and plasma tails. Its interaction with the solar wind generated, contrary to all expectation, a bow-wave of X-rays. The novel spectrum it emitted caused it to be classified as a new comet type. Our understanding of our place in the universe has been furthered by this intensely observed, spectacular event.

The comet was discovered on the 30th January as a faint smudge on the border between the constellations Hydra and Libra by the amateur Japanese observer, Yuji Hyakutake. Astronomers soon characterised its orbit and recognised, that in a span of six weeks, it would approach to within 1/10th of the earth/sun distance.

C 96 B1 Hyakutake sped inwards too rapidly for the magazines and journals which normally keep comet watchers informed. Many gained their information from the internet. The Comet Hyakutake Home Page set up by Ron Baalke at the California Institute of Technology/NASA Jet Propulsion Laboratory was one of the more widely accessed sites. Many placed their observations on the internet. Hundreds emailed comet images to Baalke's site. By the time its subject was swinging back to aphelion, his Comet Image Archive contained over 1,000 files.

This file contains thumbnails of a representative set of images taken by amateurs and professionals with apparatus ranging from pinhole cameras to large observatory instruments and satellites in orbit. Such miniatures in Baalke's archive serve to index large, high resolution images and observation notes. Here, they have been assembled into a cavalcade of tiny pictures simply to show that observers around the globe cooperated to perceive a passing celestial guest.

I am grateful to Yuji Hyakutake and all whose internet postings focused my attention on the comet. Cued in by their efforts, I saw a marvellous phenomenon. When it left southern Australia's skies, I was still able to follow it's progress via the postings of northern hemisphere observers. The enthusiastic contributors and archivists who placed forecasts, reports, images and analyses on line expanded my sense of wonder and awe. Their collective endeavour has encouraged my hope for a future that harnesses the thoughtful cooperation of all.

Via the internet I will continue to observe comet Hyakutake's passage and many other astronomical discoveries and events. But for me, Hyakutake's visit will remain special. During it, I joined the internet, a vast and growing number of individuals willing to link systems and contribute content inorder to create a prolific, priceless source of information, open to all.

Michael Gallagher
Bendigo, Australia
16th June 1996
migall@hitech.net.au