C/1968 N1 (Honda)

Metadata

Parameter Value
Designation C/1968 N1 (Honda)
Type C
Perihelion (tp_cal, UTC) 1968-08-07T22:10:35.492160Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:29:17Z
Obs used 137
NEO -
M1 5.200
K1 12.500
PC -
Osculating Elements
Parameter Value
Epoch (epoch_cal, TDB) 1968-09-04.0000000
e 1.00071634
q (au) 1.160438
a (au) -1619.950396
i (deg) 143.238254
Ω (om, deg) 106.747265
ω (w, deg) 88.715828
M (ma, deg) 0.000409

Magnitude

C/1968 N1 (Honda) · Magnitude (Full range)

Scatter + Global Linear

$$ M_a = (5.762 + 5.761\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

Model Parameters

Parameter Value
H0 5.762
n 5.761
gf 1.000
gb -0.601
k 0.800
δ90 10.000
Parameter Symbol Range Description
Absolute magnitude at 1 AU from Sun and Earth H0 -5 to 20 Intrinsic brightness of the comet
Photometric slope parameter n 2 to 6 Rate of brightness change with heliocentric distance
Forward scattering asymmetry factor gf 0.8 to 1 Degree of forward scattering
Backward scattering asymmetry factor gb -1 to -0.5 Degree of backward scattering
Partitioning coefficient k 0.8 to 1 Ratio between forward/backward scattering contributions
Dust-to-gas brightness ratio δ90 1 to 10 Relative contribution of dust scattering to gas emission

Reference: EPSC-DPS2025-160

Ephemeris

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-09-25 00:00 13:05:33.62 -45:18:37.1 HIP 63868 4.73
2026-09-25 12:00 13:05:35.37 -45:18:39.7 HIP 63868 4.81
2026-09-26 00:00 13:05:37.13 -45:18:42.5 HIP 63868 4.91
2026-09-26 12:00 13:05:38.89 -45:18:45.3 HIP 63868 5.03
2026-09-27 00:00 13:05:40.65 -45:18:48.3 HIP 63868 5.16
2026-09-27 12:00 13:05:42.42 -45:18:51.4 HIP 63868 5.30
2026-09-28 00:00 13:05:44.19 -45:18:54.6 HIP 63868 5.46
2026-09-28 12:00 13:05:45.96 -45:18:58.0 HIP 63868 5.63
2026-09-29 00:00 13:05:47.74 -45:19:01.4 HIP 63868 5.81
2026-09-29 12:00 13:05:49.52 -45:19:05.0 HIP 63868 6.01
2026-09-30 00:00 13:05:51.31 -45:19:08.7 HIP 63868 6.21
2026-09-30 12:00 13:05:53.10 -45:19:12.5 HIP 63868 6.42
2026-10-01 00:00 13:05:54.89 -45:19:16.4 HIP 63868 6.64
2026-10-01 12:00 13:05:56.68 -45:19:20.5 HIP 63868 6.86
2026-10-02 00:00 13:05:58.48 -45:19:24.6 HIP 63868 7.10
2026-10-02 12:00 13:06:00.28 -45:19:28.9 HIP 63868 7.33
2026-10-03 00:00 13:06:02.08 -45:19:33.3 HIP 63868 7.58
2026-10-03 12:00 13:06:03.88 -45:19:37.8 HIP 63868 7.83
2026-10-04 00:00 13:06:05.69 -45:19:42.5 HIP 63868 8.08
2026-10-04 12:00 13:06:07.50 -45:19:47.2 HIP 63868 8.34
2026-10-05 00:00 13:06:09.31 -45:19:52.1 HIP 63868 8.61
2026-10-05 12:00 13:06:11.12 -45:19:57.1 HIP 63868 8.88
2026-10-06 00:00 13:06:12.93 -45:20:02.2 HIP 63868 9.15
2026-10-06 12:00 13:06:14.75 -45:20:07.4 HIP 63868 9.42
2026-10-07 00:00 13:06:16.56 -45:20:12.7 HIP 63868 9.70
2026-10-07 12:00 13:06:18.38 -45:20:18.2 HIP 63868 9.98
2026-10-08 00:00 13:06:20.20 -45:20:23.7 HIP 63868 10.26
2026-10-08 12:00 13:06:22.02 -45:20:29.4 HIP 63868 10.55
2026-10-09 00:00 13:06:23.84 -45:20:35.2 HIP 63868 10.84
2026-10-09 12:00 13:06:25.66 -45:20:41.1 HIP 63868 11.13
2026-10-10 00:00 13:06:27.48 -45:20:47.1 HIP 63868 11.42
2026-10-10 12:00 13:06:29.31 -45:20:53.3 HIP 63868 11.72
2026-10-11 00:00 13:06:31.13 -45:20:59.5 HIP 63868 12.01
2026-10-11 12:00 13:06:32.95 -45:21:05.9 HIP 63868 12.31
2026-10-12 00:00 13:06:34.77 -45:21:12.3 HIP 63868 12.61
2026-10-12 12:00 13:06:36.60 -45:21:18.9 HIP 63868 12.92
2026-10-13 00:00 13:06:38.42 -45:21:25.6 HIP 63868 13.22
2026-10-13 12:00 13:06:40.24 -45:21:32.4 HIP 63868 13.52
2026-10-14 00:00 13:06:42.06 -45:21:39.3 HIP 63868 13.83
2026-10-14 12:00 13:06:43.88 -45:21:46.3 HIP 63868 14.14
2026-10-15 00:00 13:06:45.70 -45:21:53.4 HIP 63868 14.44
2026-10-15 12:00 13:06:47.52 -45:22:00.7 HIP 63868 14.75
2026-10-16 00:00 13:06:49.34 -45:22:08.0 HIP 63868 15.06