SMM 3

From IAUC 4648 (1988 August 30):

COMET 1988l (SMM 3)
O. C. St. Cyr, Solar Maximum Mission, NASA Goddard Space Flight
Center, reports his discovery of another probable sungrazing comet
with the SMM coronagraph (cf. IAUC 4621). Measurements by S. A. Beck,
High Altitude Observatory, have been reduced by the SMM Flight
Dynamics Facility:

1988 UT R.A. (1950) Decl.
June 27.63958 6 19 48 +22 46.2
27.65069 6 19 58 +22 49.8
27.66250 6 20 02 +22 52.8
27.69306 6 20 48 +23 02.4
27.70486 6 21 00 +23 06.6
27.71667 6 21 22 +23 09.0
27.72222 6 21 34 +23 13.2

As before, the measurements are estimated as good to +/- 0.1 solar
radius and +/- 0.1-deg position angle, and SMM 3 was not detected as
it receded from the sun. The estimated magnitude was very roughly -1.

The comet looks much fainter than mag -1 in these images. Mercury is mag -2 in the image from 1986 May 22.
The comet's head looks not brighter than a star of mag 4.