Skip Navigation: Avoid going through Home page links and jump straight to content

MarsWatch 1996-1997

Images of Mars from Astronomers Around the World


Linking Amateur and Professional Mars Observing Communities

for Observational Support of the Mars Pathfinder Mission


Back to the MarsWatch Home Page


23 April 1997

gt42397r.jpg

This red light CCD image of Mars was obtained by noted astroimager Gregory Terrance on April 23, 1997 (LS=108.7, De=23.9, Dia.=12.15") at 00:56 UT (CM=013.3) using a 16-inch (41-cm) f/5 Newtonian reflector, at an effective focal ratio (EFR) of f/30, coupled to a Celestron PixCel 255 CCD camera at an exposure of 0.1 seconds. The North Polar Cap (NPC) is apparently very bright to extremely bright (8-9/10) and surrounded by a dark to very dark (2-3/10) collar consisting of Ortygia, Hyperboreus Lacus, and Abalos. Cydonia appears dark to dusky (3-4/10) towards the Np. limb. Mare Acidalium appears dark to very dark (2-3/10) on and f. the CM (Callirrhoes Sinus appears as a dark (3/10), "wedge-shaped" albedo feature on the CM) apparently connected to Hyperboreus Lacus by Abalos. Niliacus Lacus appears dark (3/10) and separated from Mare Acidalium by a thin, bright (7/10) Achillis Pons. Nilokeras appears dark to dusky (3-4/10) adjacent to the f., or morning, limb with Achillis Fons visible over its northern border and Idaeus Fons over its southern border. Sinus Sabaeus appears dark (3/10) over the Sp. limb and apparently connected to Sinus Meridiani (3/10) (Brangaena (Argus) is visible as a thin, dark (3/10) projection from it's f. border over Thymiamata). Margaritifer Sinus, Vulcani Pelagus, and Mare Erythraeum appear dark (3/10) towards the Sf. limb. Oxia Palus is visible as an elongated, dark (3/10) streak Np. Margaritifer Sinus. A thin, dark (3/10) projection is visible along the f. border of Margaritifer Sinus and this may represent the southern origin of Hydaspis Sinus, a transient albedo feature observed by various well known planetary astronomers (i.e. Secchi, Dawes, Kaiser) between 1858 and 1871.

(Legend: N.=north, S.=south, p.=preceding, f.=following, Np.=north-preceding, Nf.=north-following, Sp.=south-preceding, Sf.=south-following, MLH=morning limb haze, ELH=evening limb haze, and SLH=southern limb haze)


Back to the MarsWatch Images Page