How to Report a Discovery - Discovery of many kinds of transient astronomical phenomena (e.g., comets, novae, supernovae, etc.) should be reported to the CBAT. The Bureau is responsible for assigning designations to comets and supernovae. Meteor(ite)/fireball reports should not be reported to the Bureau, but to the Fireball Data Center of the International Meteor Organization (e-mail:starex@tron.gun.de). Discoveries of new minor planets should be reported to the Minor Planet Center. A listing of the information that you should include in any discovery report concerning comets, supernovae, novae, outbursts of variable stars or features on planetary surfaces is available. If you wish to report a discovery you may report it on this discovery form. Please ensure that you have read the documentation on what information you should include in your report--incomplete reports may be ignored. When you have completed the discovery form it will be e-mailed to the Bureau staff for processing. Alternatively, you may e-mail a report directly to cbat@cfa.harvard.edu. Observable Comets - This page lists links to orbital elements and ephemerides of (potentially) observable comets. Orbital elements and ephemerides are available. Recent Comet Discoveries and Recoveries Comet chasing is the visual observation of telescopic comets What's Observable Tonight? (Calculator) What's a Comet Sound Like? Recent News and Observations - The comets are given in order of designation; first the long period comets and then the short period comets. Under each is the "Last Updated" date, which indicates the last date that one or more observations were posted for the specific comet. Current and Future Comets - To a nonastronomer a comet is a fuzzy object in the sky. My attempts to get people interested in comets in recent years have usually been met with "Is that all?" or "Gee, thanks for dragging me out here in the middle of the night to see that fuzzy spot!" To astronomers a comet is a frozen body composed of various ices and dust, or, to quote astronomer Fred Whipple, it is a "dirty snowball." What is it that makes comets exciting to Recent News and Observations -- The comets are given in order of designation; first the long period comets and then the short period comets. Under each is the "Last Updated" date, which indicates the last date that one or more observations were posted for the specific comet. StarDate Online: Comets The STScI Digitized Sky Survey A Brief History of Comets I, II Fix: Chapter 15 Solar System Debris Interactive Star Atlas     Object Catalogues: Periodic Comets Comets are small, fragile, irregularly shaped bodies composed of a mixture of non-volatile grains and frozen gases. They have highly elliptical orbits that bring them very close to the Sun and swing them deeply into space, often beyond the orbit of Pluto. Comet structures are diverse and very dynamic, but they all develop a surrounding cloud of diffuse material, called a coma, that usually grows in size and brightness as the comet approaches the Sun. Usually a small, bright nucleus (less than 10 km in diameter) is visible in the middle of the coma. The coma and the nucleus together constitute the head of the comet. Also see: Views of the Solar System Comets are sometimes called dirty snowballs or "icy mudballs". They are a mixture of ices (both water and frozen gases) and dust that for some reason didn't get incorporated into planets when the solar system was formed. This makes them very interesting as samples of the early history of the solar system. Also see: The Nine Planets Deep Impact -- On July 4, 2005, the Deep Impact spacecraft arrives at Comet Tempel 1 to impact it with a 370-kg (~820-lbs) mass. On impact, a crater is produced expected to range in size from that of a house to that of a football stadium, and two to fourteen stories deep. Ice and dust debris is ejected from the crater revealing fresh material beneath. Sunlight reflecting off the ejected material provides a dramatic brightening that fades slowly as the debris dissipates into space or falls back onto the comet. Images from cameras and a spectrometer are sent to Earth covering the approach, the impact and its aftermath. The effects of the collision with the comet will also be observable from certain locations on Earth and in some cases with smaller telescopes. The data is analyzed and combined with that of other NASA and international comet missions. Results from these missions will lead to a better understanding of both the solar system's formation and implications of comets colliding with Earth. Comet Borrelly's Nucleus -- What does a comet nucleus look like? To answer this question, NASA controllers drove an aging probe through the hostile environs of a distant comet, expecting that even if comet fragments disabled the spacecraft, it would be worth the risk. The probe, Deep Space 1, survived. Pictured at right is the most detailed image ever taken of a comet nucleus, obtained Saturday by Deep Space 1 and released yesterday by NASA. Comet Borrelly's nucleus is seen to be about 8 kilometers long with mountains, faults, grooves, smooth rolling planes, and materials of vastly different reflectance. Light colored regions are present near the center and seem to give rise to dust jets seen in Borrelly's coma, visible in distant images of the comet. Previously, the best image of a comet nucleus came from the Giotto mission to Comet Halley in 1986. Deep Space 1 images of Borrelly add welcomed bedrock to understanding Solar System history and to the accurate prediction of future brightness changes of notoriously fickle comets. Comet Shoemaker-Levy Home Page (JPL) - From July 16 through July 22, 1994, pieces of an object designated as Comet P/Shoemaker-Levy 9 collided with Jupiter. This is the first collision of two solar system bodies ever to be observed, and the effects of the comet impacts on Jupiter's atmosphere have been simply spectacular and beyond expectations. Comet Shoemaker-Levy 9 consists of 21 discernable fragments with diameters estimated at up to 2 kilometers.     © Copyright 2007 - Samuel J. Wormley   by swormley1@mchsi.com