Lightcurve and images of C/2004 F4 (Bradfield)
According to IAUC 8319 Bill Bradfield discovered
his 18th comet on March 23 and 24 with his 25-cm
reflector from a country location near his home in
Yankalilla (South Australia). Because of its small
elongation, deep in evening twilight, it could only
be confirmed on April 8/9.
The latest orbital elements (MPEC 2004-M49) show it
passed perihelion on April 17.090, only 0.168 AU
from the sun. Around that time it made a spectacular
passage through the SOHO C3-field.
It became observable again for earthbound observers
in the Northern Hemisphere on April 23, as a magn. 3
object, low in the morning sky.
The orbital elements indicate this comet moves in an
elliptical orbit with a period of about 3800 years,
which explains why it survived perihelion, despite
being of rather low intrinsic brightness.
A preliminary lightcurve and photometric parameters
are given below.
C/2004 F4 (Bradfield) on April 27.14 UT. This image was taken by Juan José González Suárez from the
Cantabrian Mountains, at an altitude of 1700m, on the Alto del Castro, León, Northern Spain.
He used a Nikkor 50 mm f/1.8 lens for this 25s exposure on Fuji Superia 800 colour film.