73P-BT/Schwassmann-Wachmann 3

73P-BT/Schwassmann-Wachmann 3
Reported observations:
2017 Mar. 06.73 UT: m1=12.2, Dia.=0.9’, DC=3/4, ... 25-cm L f:5 (83x) ... Chris Wyatt (Walcha, NSW, Australia) [Faint tail visible 2.4’ in length in P.A. 265°; Inner coma appears elongated East-West. Comparison stars checked using APASS data in Guide 9.0; Method= M; Cat= AQ]
2017 Feb. 23.72 UT: m1=11.9, Dia.=1.1’, DC=3/4, ... 25-cm L f:5 (83x) ... Chris Wyatt (Walcha, NSW, Australia) [Coma elongated to the West approximately; Inner coma opaque. Does not enhance in Swan Band filter. Comparison stars checked using APASS data in Guide 9.0; Method= M; Cat= AQ]
2017 Feb. 21.23 UT: m1=9.8, Dia.=3.5', DC=2, ... 20-cm SCT (100x) ... Juan Jose Gonzalez (Alto de la Camperona, Leon, Spain; Alt. 1600 m, 42º 51' N, 5º 12' W) [Sidgwick method. Tycho-2 comparison stars. The visually observed faint and wide halo-like common coma of 73P is surrounding the primary and the brighter secondary component BT (this secondary is evolving after the recent outburst recorded in CCD images). Both central condensations were not individually detected in the present observation due to faintness, small separation (near 0.5 arcmin), instrumental (20 cm SCT at 100x) and observing conditions : interference from the nearby Moon (phase 0.28) and low altitude (9 deg) at the start of astronomical twilight. Field stars checked in DSS. Background star of mag 12.3 (GSC) in coma. Mountain location, very clear sky]
2017 Feb. 17.72 UT: m1=10.8, Dia.=1’, DC=2/3, ... 25-cm L f:5 (83x) ... Chris Wyatt (Walcha, NSW, Australia) [Fragment BT. Moonlight. Coma small, diffuse and opaque. Slight brightening to centre, no enhancement in Swan Band filter. Comparison stars checked using APASS data in Guide 9.0; Method= S; Cat= AQ]