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Observer: Mark Gransden
Location:Jindera, New South Wales, Australia Optics:50mm lens, f/1.8. Exposure: 20 seconds and ASA 800 film. Hale-Bopp with Orion Nebula and Sirius. |
Observers: Hans-Ulrich Kaeufl, Yan Fernandez
Location:European Southern Observatory, La Silla, Chile Optics:Thermal Infrared MultiMode Instrument (TIMMI) at the ESO 3.6-m telescope. Following the perihelion passage on April 1, 1997, Comet Hale-Bopp has moved southwards and also closer to the Sun, as seen in the sky. During a period of about two months (mid-May to mid-July), it has been virtually impossible to obtain conventional images with optical detectors. Now, however, Hans-Ulrich Kaeufl (ESO) and Yan Fernandez (Univ. of Maryland, USA) have succeeded in taking the first mid-infrared images after the perihelion passage from the ESO La Silla Observatory, by means of the TIMMI (Thermal Infrared MultiMode Instrument) at the ESO 3.6-m telescope. These images were obtained during a daytime observing session when the comet was only 31º from the Sun in the sky. This is about as close as one can observe with this instrumental combination. The images have not yet been studied in detail and a scientific evaluation is yet to follow. At that time, the comet was `behind' the Sun, at a geocentric distance of 2.785 AU (417 million km) and it was seen almost `head-on'; the Sun-comet-Earth angle (the phase) was only 15º. |