Observation of May 1, 1997
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Begin: 21h 00m UT
End: 22h 30m
Ls = 112, diam = 11.5 arcsec
Drawings: 21h 15m, CM 246; 21h 45m, CM 254.
Semi-apo refractor of Osservatorio di Torino, 420 mm f/16.7, 412 X. Seeing
(Antoniadi) III, good transparency.
Notes:
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NPC is pure white (intensity 0) as is a crescent-shaped white patch preceding
it. Its contour is black, thicker on the f. side.
Strong limb brightening at p. limb of clearly yellowish colour. The colour of the haze at f. limb, partially extended over Syrtis M., is much more "blue" in comparison. This haze remains visible till the end of the observation (see small sketch). The difference in intensity between the middle-southern part of Syrtis M. and its northern end is striking. Hellas is very bright. With W38A Syrtis Major is completely invisible, only a diffuse bright patch is observable in its place.
Elysium bright in the middle, both without filters
and with W38A.
Paolo Tanga
Mars Program Coordinator
Sezione Pianeti - Unione Astrofili Italiani