Forum der Vereinigung der Sternfreunde

Taras Prystavski
4 hrs ·
Today I imaged again comet P/2007 R4 (Garradd). I quickly found it where I expected - just 6' east from the predicted ephemeris position. Probably, due to slightly worse weather conditions I saw only a hint of tail. Comet is very faint and still at 19.4 mag.

COMET P/2007 R4 = P/2021 U2 (Garradd)

T. Prystavski reports the recovery of comet P/2007 R4 (Garradd) on CCD
images taken on Oct. 24 and 26 UT from iTelescope Observatory, Siding Spring
(Q62). He notes the comet's appearance was slightly elongated with a hint of
a tail. An additional tracklet was subsequently identified with this comet,
taken from Possum Observatory (E94) on Aug. 15.


P/2007 R4 (Garradd)
Epoch 2021 Dec. 12.0 TT = JDT 2459560.5
T 2021 Dec. 8.50597 TT Rudenko
q 1.9576133 (2000.0) P Q
n 0.06821672 Peri. 282.59447 +0.92543424 -0.15657858
a 5.9321052 Node 87.19258 +0.29276848 +0.87356284
e 0.6699969 Incl. 20.20973 -0.24053708 +0.46083740
P 14.4
From 99 observations 2007 Aug. 12-2021 Oct. 26, mean residual 0".9.

COMET P/2021 U2 = P/2007 R4 (GARRADD)
Comet P/2007 R4 (cf. IAUC 8870) has been recovered independently on CCD
images obtained by J. Drummond (Gisborne, New Zealand, 0.41-m f/4.5 Newtonian
reflector) and by T. Prystavski (Ukraine; remotely using an iTelescope 0.51-m
f/6.8 astrograph at Siding Spring, NSW, Australia). On Aug. 18, Drummond
sent his astrometric observations from Aug. 15 of two objects that he noted
were near the position of P/2007 R4; one of those two objects now has been
confirmed as that of P/2007 R4