C/2011 F1 (LINEAR) was discovered on 2011, Mar. 17.28 by the LINEAR survey with a 1.0-m f/2.15 reflector + CCD.
It was subsequently placed on the NEO Confirmation Page of the Minor Planet Center under the temporary designation BY58897.
The first clear day here in northern Italy, after its discovery, was the night between Mar. 20 and 21; fortunately it was still in the NEO Confirmation Page.
The sky was clear with good seeing but with a strong moonlight (almost Full Moon 80° away), but nontheless we could confirm its cometary features.
Three separate stacks (each made by 30×30 seconds images) reveal a FWHM 30% larger than stars nearby of similar brightness.
A total stack of 90×30 seconds also reveals a faint elongation of the coma in PA 250°.
The discovery was announced on IAUC 9202 (subscription required) and the astrometry published on MPEC 2011-F15.
Below is our image:
“G.V.Schiaparelli” Astronomical Observatory