C/2012 T5 Bressi
more info
Comet C/2012 T5 was discovered on 14 October 2012 by Terry H. Bressi (Spacewatch), that is more than 4 months before its perihelion passage. It was observed until 21 March 2013 (see picture).
C/2012 T5 had its closest approach to the Earth on 25 February 2013 (0.913 au), a day after its perihelion passage.
Comet was lost a month after perihelion passage and Sekanina (2019) concluded that this Oort Cloud comet did not survive the observed perihelion passage.
Original value of 1/a is significantly negative for solutions based on entire data set. The preferred solution (based on pre-perihelion data taken at larger heliocentric distances than 1.33au) gives also negative value of original 1/a; however, within its uncertainty of about 1.5 sigma this comet can came from the Oort Cloud.
See also Królikowska 2020.

solution description
number of observations 702
data interval 2012 10 14 – 2013 03 21
data type significantly more measurements before perihelion (PRE+)
data arc selection entire data set (STD)
range of heliocentric distances 2.58 au – 0.32 au (perihelion) – 0.75 au
type of model of motion NT - non-gravitational orbits for asymmetric, standard g(r)
data weighting YES
number of residuals 1398
RMS [arcseconds] 0.72
orbit quality class 2a
previous orbit statistics, both Galactic and stellar perturbations were taken into account
no. of returning VCs in the swarm 0
no. of escaping VCs in the swarm 5001
no. of hyperbolas among escaping VCs in the swarm 5001 *
previous reciprocal semi-major axis [10-6 au-1] -200.67 – -166.71 – -143.81
previous perihelion distance [au] 0.748 – 0.824 – 0.948
synchronous stop epoch [Myr] -0.97 S
percentage of VCs with qprev < 10100
Time distribution of positional observations with corresponding heliocentric (red curve) and geocentric (green curve) distance at which they were taken. The horizontal dotted line shows the perihelion distance for a given comet whereas vertical dotted line — the moment of perihelion passage.
previous orbit statistics, here only the Galactic tide has been included
no. of returning VCs in the swarm 0
no. of escaping VCs in the swarm 5001
no. of hyperbolas among escaping VCs in the swarm 5001 *
previous reciprocal semi-major axis [10-6 au-1] -200.68 – -166.72 – -143.83
previous perihelion distance [au] 0.679 – 0.747 – 0.859
synchronous stop epoch [Myr] -1.02 S
percentage of VCs with qprev < 10100