| 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) |
| 2026-05-12 00:00 |
05:10:22.20 |
+20:53:19.5 |
HIP 24116 |
20.06 |
| 2026-05-12 12:00 |
05:10:23.71 |
+20:53:22.0 |
HIP 24116 |
20.00 |
| 2026-05-13 00:00 |
05:10:25.21 |
+20:53:24.6 |
HIP 24116 |
19.95 |
| 2026-05-13 12:00 |
05:10:26.73 |
+20:53:27.1 |
HIP 24116 |
19.90 |
| 2026-05-14 00:00 |
05:10:28.25 |
+20:53:29.7 |
HIP 24116 |
19.86 |
| 2026-05-14 12:00 |
05:10:29.77 |
+20:53:32.2 |
HIP 24116 |
19.82 |
| 2026-05-15 00:00 |
05:10:31.31 |
+20:53:34.8 |
HIP 24116 |
19.79 |
| 2026-05-15 12:00 |
05:10:32.84 |
+20:53:37.4 |
HIP 24116 |
19.77 |
| 2026-05-16 00:00 |
05:10:34.39 |
+20:53:39.9 |
HIP 24116 |
19.75 |
| 2026-05-16 12:00 |
05:10:35.94 |
+20:53:42.5 |
HIP 24116 |
19.74 |
| 2026-05-17 00:00 |
05:10:37.49 |
+20:53:45.0 |
HIP 24116 |
19.74 |
| 2026-05-17 12:00 |
05:10:39.05 |
+20:53:47.6 |
HIP 24116 |
19.74 |
| 2026-05-18 00:00 |
05:10:40.62 |
+20:53:50.1 |
HIP 24116 |
19.75 |
| 2026-05-18 12:00 |
05:10:42.19 |
+20:53:52.7 |
HIP 24116 |
19.76 |
| 2026-05-19 00:00 |
05:10:43.76 |
+20:53:55.2 |
HIP 24116 |
19.79 |
| 2026-05-19 12:00 |
05:10:45.35 |
+20:53:57.8 |
HIP 24116 |
19.81 |
| 2026-05-20 00:00 |
05:10:46.93 |
+20:54:00.3 |
HIP 24116 |
19.85 |
| 2026-05-20 12:00 |
05:10:48.52 |
+20:54:02.9 |
HIP 24116 |
19.89 |
| 2026-05-21 00:00 |
05:10:50.12 |
+20:54:05.4 |
HIP 24116 |
19.94 |
| 2026-05-21 12:00 |
05:10:51.71 |
+20:54:07.9 |
HIP 24116 |
20.00 |
| 2026-05-22 00:00 |
05:10:53.32 |
+20:54:10.5 |
HIP 24116 |
20.07 |
| 2026-05-22 12:00 |
05:10:54.92 |
+20:54:13.0 |
HIP 24116 |
20.14 |
| 2026-05-23 00:00 |
05:10:56.54 |
+20:54:15.5 |
HIP 24116 |
20.21 |
| 2026-05-23 12:00 |
05:10:58.15 |
+20:54:18.0 |
HIP 24116 |
20.30 |
| 2026-05-24 00:00 |
05:10:59.77 |
+20:54:20.6 |
HIP 24116 |
20.39 |
| 2026-05-24 12:00 |
05:11:01.39 |
+20:54:23.1 |
HIP 24116 |
20.49 |
| 2026-05-25 00:00 |
05:11:03.02 |
+20:54:25.6 |
HIP 24116 |
20.59 |
| 2026-05-25 12:00 |
05:11:04.65 |
+20:54:28.1 |
HIP 24116 |
20.71 |
| 2026-05-26 00:00 |
05:11:06.28 |
+20:54:30.6 |
HIP 24116 |
20.82 |
| 2026-05-26 12:00 |
05:11:07.92 |
+20:54:33.1 |
HIP 24116 |
20.95 |
| 2026-05-27 00:00 |
05:11:09.56 |
+20:54:35.6 |
HIP 24116 |
21.08 |
| 2026-05-27 12:00 |
05:11:11.20 |
+20:54:38.1 |
HIP 24116 |
21.22 |
| 2026-05-28 00:00 |
05:11:12.85 |
+20:54:40.6 |
HIP 24116 |
21.36 |
| 2026-05-28 12:00 |
05:11:14.50 |
+20:54:43.1 |
HIP 24116 |
21.51 |
| 2026-05-29 00:00 |
05:11:16.15 |
+20:54:45.5 |
HIP 24116 |
21.67 |
| 2026-05-29 12:00 |
05:11:17.80 |
+20:54:48.0 |
HIP 24116 |
21.83 |
| 2026-05-30 00:00 |
05:11:19.46 |
+20:54:50.5 |
HIP 24116 |
21.99 |
| 2026-05-30 12:00 |
05:11:21.12 |
+20:54:53.0 |
HIP 24116 |
22.17 |
| 2026-05-31 00:00 |
05:11:22.78 |
+20:54:55.4 |
HIP 24116 |
22.35 |
| 2026-05-31 12:00 |
05:11:24.44 |
+20:54:57.9 |
HIP 24116 |
22.53 |
| 2026-06-01 00:00 |
05:11:26.11 |
+20:55:00.3 |
HIP 24116 |
22.72 |
| 2026-06-01 12:00 |
05:11:27.77 |
+20:55:02.8 |
HIP 24116 |
22.91 |
| 2026-06-02 00:00 |
05:11:29.44 |
+20:55:05.2 |
HIP 24116 |
23.11 |