C/2007 F1 (LONEOS)

For other comets of the same name, see Comet LONEOS.

C/2007 F1 (LONEOS) is a hyperbolic comet discovered on March 19, 2007 as part as the Lowell Observatory Near Earth Object Search (LONEOS). The comet reached perihelion, or closest approach to the Sun on October 28, 2007.^[1]

C/2007 F1 (LONEOS)

The comet on 29 October 2007 by STEREO A
Discovery
Discovered by	Brian A. Skiff
Discovery date	March 19, 2007
Orbital characteristics
Epoch	June 7, 2007 (JD 2454258.5)
Aphelion	N/A
Perihelion	0.40237 AU
Semi-major axis	N/A
Eccentricity	1.00009[1] 1.000021 (epoch 2011+)[2]
Orbital period	N/A
Inclination	116.08°
Last perihelion	October 28, 2007
Next perihelion	ejection
Physical characteristics[3][4]
Mean radius	0.75±0.10 km
Mass	7.4×1011 kg
Mean density	440±70 kg/m3
Comet total magnitude (M1)	10.8[1]

The comet reached 5th magnitude in October, making it visible in binoculars, lying near the western horizon at the end of the twilight,^[5] before starting slowly to dim on its way out of the Solar System. It continued to move south in the sky and became visible to southern hemisphere comet chasers in mid-November.

The comet was also observed from both the STEREO spacecraft, first by STEREO-B on October 22 and then by STEREO-A for several days starting from October 28^[6] as the comet had just passed perihelion and was receding from the Sun.