| Parameter |
Value |
| Designation |
C/1976 J1 (Harlan) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1976-11-03T03:38:09.047040Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:24Z |
| Obs used |
41 |
| NEO |
- |
| M1 |
9.000 |
| K1 |
10.250 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1976-06-27.0000000 |
| e |
0.99974240 |
| q (au) |
1.568851 |
| a (au) |
6090.351371 |
| i (deg) |
38.805628 |
| Ω (om, deg) |
81.411634 |
| ω (w, deg) |
193.265529 |
| M (ma, deg) |
359.999732 |
Magnitude
Scatter + Global Linear
$$
M_a = (13.852 + 2.696\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
13.852 |
| n |
2.696 |
| gf |
0.995 |
| gb |
-1.000 |
| 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) |
| 2026-03-26 00:00 |
05:08:42.71 |
+20:49:43.2 |
HIP 23963 |
19.40 |
| 2026-03-26 12:00 |
05:08:43.22 |
+20:49:45.0 |
HIP 23963 |
19.40 |
| 2026-03-27 00:00 |
05:08:43.74 |
+20:49:46.8 |
HIP 23963 |
19.40 |
| 2026-03-27 12:00 |
05:08:44.27 |
+20:49:48.7 |
HIP 23963 |
19.40 |
| 2026-03-28 00:00 |
05:08:44.82 |
+20:49:50.5 |
HIP 23963 |
19.40 |
| 2026-03-28 12:00 |
05:08:45.38 |
+20:49:52.4 |
HIP 23963 |
19.40 |
| 2026-03-29 00:00 |
05:08:45.96 |
+20:49:54.3 |
HIP 23963 |
19.40 |
| 2026-03-29 12:00 |
05:08:46.55 |
+20:49:56.2 |
HIP 23963 |
19.41 |
| 2026-03-30 00:00 |
05:08:47.15 |
+20:49:58.2 |
HIP 23963 |
19.41 |
| 2026-03-30 12:00 |
05:08:47.76 |
+20:50:00.1 |
HIP 23963 |
19.41 |
| 2026-03-31 00:00 |
05:08:48.39 |
+20:50:02.1 |
HIP 23963 |
19.42 |
| 2026-03-31 12:00 |
05:08:49.04 |
+20:50:04.0 |
HIP 23963 |
19.42 |
| 2026-04-01 00:00 |
05:08:49.69 |
+20:50:06.0 |
HIP 23963 |
19.43 |
| 2026-04-01 12:00 |
05:08:50.36 |
+20:50:08.0 |
HIP 23963 |
19.44 |
| 2026-04-02 00:00 |
05:08:51.04 |
+20:50:10.0 |
HIP 23963 |
19.45 |
| 2026-04-02 12:00 |
05:08:51.74 |
+20:50:12.0 |
HIP 23963 |
19.46 |
| 2026-04-03 00:00 |
05:08:52.45 |
+20:50:14.0 |
HIP 23963 |
19.47 |
| 2026-04-03 12:00 |
05:08:53.17 |
+20:50:16.1 |
HIP 23963 |
19.48 |
| 2026-04-04 00:00 |
05:08:53.90 |
+20:50:18.1 |
HIP 23963 |
19.49 |
| 2026-04-04 12:00 |
05:08:54.65 |
+20:50:20.2 |
HIP 23963 |
19.51 |
| 2026-04-05 00:00 |
05:08:55.41 |
+20:50:22.3 |
HIP 23963 |
19.52 |
| 2026-04-05 12:00 |
05:08:56.18 |
+20:50:24.4 |
HIP 23963 |
19.54 |
| 2026-04-06 00:00 |
05:08:56.97 |
+20:50:26.5 |
HIP 23963 |
19.56 |
| 2026-04-06 12:00 |
05:08:57.77 |
+20:50:28.6 |
HIP 23963 |
19.58 |
| 2026-04-07 00:00 |
05:08:58.58 |
+20:50:30.7 |
HIP 23963 |
19.61 |
| 2026-04-07 12:00 |
05:08:59.40 |
+20:50:32.9 |
HIP 23963 |
19.63 |
| 2026-04-08 00:00 |
05:09:00.24 |
+20:50:35.0 |
HIP 23963 |
19.66 |
| 2026-04-08 12:00 |
05:09:01.09 |
+20:50:37.2 |
HIP 23963 |
19.69 |
| 2026-04-09 00:00 |
05:09:01.95 |
+20:50:39.4 |
HIP 23963 |
19.72 |
| 2026-04-09 12:00 |
05:09:02.82 |
+20:50:41.5 |
HIP 23963 |
19.76 |
| 2026-04-10 00:00 |
05:09:03.71 |
+20:50:43.7 |
HIP 23963 |
19.79 |
| 2026-04-10 12:00 |
05:09:04.61 |
+20:50:45.9 |
HIP 23963 |
19.83 |
| 2026-04-11 00:00 |
05:09:05.52 |
+20:50:48.2 |
HIP 23963 |
19.87 |
| 2026-04-11 12:00 |
05:09:06.44 |
+20:50:50.4 |
HIP 23963 |
19.92 |
| 2026-04-12 00:00 |
05:09:07.37 |
+20:50:52.6 |
HIP 23963 |
19.96 |
| 2026-04-12 12:00 |
05:09:08.32 |
+20:50:54.9 |
HIP 23963 |
20.01 |
| 2026-04-13 00:00 |
05:09:09.28 |
+20:50:57.1 |
HIP 23963 |
20.06 |
| 2026-04-13 12:00 |
05:09:10.25 |
+20:50:59.4 |
HIP 23963 |
20.12 |
| 2026-04-14 00:00 |
05:09:11.23 |
+20:51:01.7 |
HIP 23963 |
20.18 |
| 2026-04-14 12:00 |
05:09:12.22 |
+20:51:04.0 |
HIP 23963 |
20.24 |
| 2026-04-15 00:00 |
05:09:13.23 |
+20:51:06.3 |
HIP 23963 |
20.30 |
| 2026-04-15 12:00 |
05:09:14.25 |
+20:51:08.6 |
HIP 23963 |
20.37 |
| 2026-04-16 00:00 |
05:09:15.27 |
+20:51:10.9 |
HIP 23963 |
20.44 |