The next MEPCO is coming ... to Bulgaria, in early August, 1999!
For details on this astronomical conference just before the total solar eclipse click here!

Kiss your 'mini-comets' goodbye... A bizarre chapter in the history of science is apparently coming to a close: Not only do the much-discussed 'small comets' not exist - even the primary evidence for this mysterious geophysical phenomenon has now been shown to be instrumental artefacts in the camera(s) of satellites. Those 'atmospheric holes' had first caused a stir in 1986 and again in 1997 when their reality had apparently been demonstrated by a new and better satellite (see a minor item in Update #48). Since then, however, other scientists have had the opportunity to study the staggering consequences of the hypothetical small comet hail in great detail (see e.g. Update #66 item 3) - and the images themselves. Paper after paper has been published already, questioning the physical reality of the dark spots. E.g. in the GRL 25#16 of Aug. 15, 1998 (p. 3063-6), Parks & al. have compared UV images of the Earth from 2 different Polar instruments and shown that the detected spots fail all tests for physical reality. Now new papers are scheduled for publication October 1 in the same journal, Geophysical Research Letters, where Mozer & al. and McFadden & al. once more attack the reality of the dark spots. They state that their study "differs from all others that have objected to the small-comet hypothesis in that it considers events produced by the major proponents of this hypothesis from data provided by their own Polar instrument." Both papers analyze raw data for one day provided by Frank and Sigwarth and additional data in the form of 700,000 pixel clusters, covering 120 days, posted on the web and known as the Iowa catalog. McFadden & al. investigate the characteristics of the dark pixels in relation to expected noise from the individual components of the two cameras. Using computer simulations, they show that the dark pixels seen in the satellite data from both cameras are entirely consistent with instrumental noise. Mozer & al. investigate the distribution of the dark pixels by altitude. They show that there is no appreciable height dependence. The researchers also note that the same pattern of dark pixels is seen in images of the nighttime sky as in sunlit images, which would not be the case if they were caused by external objects such as small comets. (Partially adapted from AGU Press Release #31 of Sept. 8, 1998)

The latest findings regarding the instrumental nature of the 'dark spots' in the Polar images. The Small Comets Believers pages and the homepage of their main proponent. The current image of the Earth from the controversial instrument. The initial NASA Release celebrating the Polar data. And where the debate was 1/2 year later. Also other views from the time and stories from ABCNEWS and Sky & Telescope.

In a Nutshell: Another rocket disaster: A Ukrainian Zenit has failed to bring 12 Globalstar satellites into orbit - stories by ABCNEWS, SpaceViews and the Globalstar homepage. / The Delta 2, however, flies again and has launched more Iridiums - but the satellite phone system's operations will only begin Nov. 1st, not Sept. 23rd.

North Korean launch still mysterious: While the N. Korean news agency continues to celebrate a working satellite in orbit with detailed reports (2 stories from Sept. 7th and stories # 1, 2 and 3 from Sept. 8th), the U.S. Space Command doesn't see a thing! More background on N. Korea's space program also from the FAS. / The recovery of SOHO continues: a current story and technical status reports - the firing of the thrusters is planned for next week!

A new, robotic H-Alpha Survey is covering the whole Southern sky and will be used for cosmological data reduction. / The production of the 2nd 6.4 m mirror for the Magellan project is documented here. / And more stories & pictures from the Aug. 22nd annular eclipse have been collected.

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