| 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 |
1.000 |
| 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) |
| 2026-07-29 00:00 |
05:14:24.39 |
+20:58:35.0 |
HIP 24456 |
8.25 |
| 2026-07-29 12:00 |
05:14:25.55 |
+20:58:36.0 |
HIP 24456 |
8.07 |
| 2026-07-30 00:00 |
05:14:26.71 |
+20:58:37.1 |
HIP 24456 |
7.90 |
| 2026-07-30 12:00 |
05:14:27.86 |
+20:58:38.1 |
HIP 24456 |
7.73 |
| 2026-07-31 00:00 |
05:14:28.99 |
+20:58:39.0 |
HIP 24456 |
7.57 |
| 2026-07-31 12:00 |
05:14:30.12 |
+20:58:40.0 |
HIP 24456 |
7.42 |
| 2026-08-01 00:00 |
05:14:31.24 |
+20:58:41.0 |
HIP 24456 |
7.28 |
| 2026-08-01 12:00 |
05:14:32.34 |
+20:58:41.9 |
HIP 24456 |
7.14 |
| 2026-08-02 00:00 |
05:14:33.44 |
+20:58:42.8 |
HIP 24456 |
7.01 |
| 2026-08-02 12:00 |
05:14:34.52 |
+20:58:43.7 |
HIP 24456 |
6.89 |
| 2026-08-03 00:00 |
05:14:35.60 |
+20:58:44.6 |
HIP 24456 |
6.78 |
| 2026-08-03 12:00 |
05:14:36.66 |
+20:58:45.5 |
HIP 24456 |
6.67 |
| 2026-08-04 00:00 |
05:14:37.71 |
+20:58:46.4 |
HIP 24456 |
6.58 |
| 2026-08-04 12:00 |
05:14:38.75 |
+20:58:47.2 |
HIP 24456 |
6.49 |
| 2026-08-05 00:00 |
05:14:39.78 |
+20:58:48.0 |
HIP 24456 |
6.41 |
| 2026-08-05 12:00 |
05:14:40.80 |
+20:58:48.8 |
HIP 24456 |
6.35 |
| 2026-08-06 00:00 |
05:14:41.81 |
+20:58:49.6 |
HIP 24456 |
6.29 |
| 2026-08-06 12:00 |
05:14:42.81 |
+20:58:50.4 |
HIP 24456 |
6.23 |
| 2026-08-07 00:00 |
05:14:43.80 |
+20:58:51.1 |
HIP 24456 |
6.19 |
| 2026-08-07 12:00 |
05:14:44.77 |
+20:58:51.9 |
HIP 24456 |
6.16 |
| 2026-08-08 00:00 |
05:14:45.73 |
+20:58:52.6 |
HIP 24456 |
6.13 |
| 2026-08-08 12:00 |
05:14:46.69 |
+20:58:53.3 |
HIP 24456 |
6.11 |
| 2026-08-09 00:00 |
05:14:47.63 |
+20:58:54.0 |
HIP 24456 |
6.10 |
| 2026-08-09 12:00 |
05:14:48.56 |
+20:58:54.6 |
HIP 24456 |
6.10 |
| 2026-08-10 00:00 |
05:14:49.47 |
+20:58:55.3 |
HIP 24456 |
6.11 |
| 2026-08-10 12:00 |
05:14:50.38 |
+20:58:55.9 |
HIP 24456 |
6.12 |
| 2026-08-11 00:00 |
05:14:51.27 |
+20:58:56.5 |
HIP 24456 |
6.14 |
| 2026-08-11 12:00 |
05:14:52.15 |
+20:58:57.1 |
HIP 24456 |
6.17 |
| 2026-08-12 00:00 |
05:14:53.02 |
+20:58:57.7 |
HIP 24456 |
6.20 |
| 2026-08-12 12:00 |
05:14:53.88 |
+20:58:58.3 |
HIP 24456 |
6.24 |
| 2026-08-13 00:00 |
05:14:54.73 |
+20:58:58.8 |
HIP 24456 |
6.28 |
| 2026-08-13 12:00 |
05:14:55.56 |
+20:58:59.4 |
HIP 24456 |
6.33 |
| 2026-08-14 00:00 |
05:14:56.38 |
+20:58:59.9 |
HIP 24456 |
6.38 |
| 2026-08-14 12:00 |
05:14:57.19 |
+20:59:00.4 |
HIP 24456 |
6.44 |
| 2026-08-15 00:00 |
05:14:57.98 |
+20:59:00.9 |
HIP 24456 |
6.50 |
| 2026-08-15 12:00 |
05:14:58.77 |
+20:59:01.3 |
HIP 24456 |
6.56 |
| 2026-08-16 00:00 |
05:14:59.54 |
+20:59:01.8 |
HIP 24456 |
6.63 |
| 2026-08-16 12:00 |
05:15:00.30 |
+20:59:02.2 |
HIP 24456 |
6.70 |
| 2026-08-17 00:00 |
05:15:01.04 |
+20:59:02.6 |
HIP 24456 |
6.77 |
| 2026-08-17 12:00 |
05:15:01.78 |
+20:59:03.0 |
HIP 24456 |
6.85 |
| 2026-08-18 00:00 |
05:15:02.50 |
+20:59:03.4 |
HIP 24456 |
6.93 |
| 2026-08-18 12:00 |
05:15:03.20 |
+20:59:03.7 |
HIP 24456 |
7.00 |
| 2026-08-19 00:00 |
05:15:03.90 |
+20:59:04.1 |
HIP 24456 |
7.08 |