| Parameter |
Value |
| Designation |
C/2000 OF8 (Spacewatch) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2001-08-04T19:13:02.890560Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:05Z |
| Obs used |
72 |
| NEO |
- |
| M1 |
12.800 |
| K1 |
4.750 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2000-09-24.0000000 |
| e |
1.00180402 |
| q (au) |
2.172785 |
| a (au) |
-1204.412900 |
| i (deg) |
152.432608 |
| Ω (om, deg) |
117.090492 |
| ω (w, deg) |
256.080338 |
| M (ma, deg) |
-0.007423 |
Magnitude
Scatter + Global Linear
$$
M_a = (14.880 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
14.880 |
| n |
2.000 |
| 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) |
| 2026-03-26 00:00 |
04:13:04.59 |
+42:33:03.3 |
HIP 19744 |
10.20 |
| 2026-03-26 12:00 |
04:13:06.10 |
+42:32:54.5 |
HIP 19744 |
9.95 |
| 2026-03-27 00:00 |
04:13:07.64 |
+42:32:45.8 |
HIP 19744 |
9.71 |
| 2026-03-27 12:00 |
04:13:09.20 |
+42:32:37.2 |
HIP 19744 |
9.46 |
| 2026-03-28 00:00 |
04:13:10.79 |
+42:32:28.7 |
HIP 19744 |
9.21 |
| 2026-03-28 12:00 |
04:13:12.41 |
+42:32:20.4 |
HIP 19744 |
8.97 |
| 2026-03-29 00:00 |
04:13:14.04 |
+42:32:12.1 |
HIP 19744 |
8.72 |
| 2026-03-29 12:00 |
04:13:15.70 |
+42:32:04.0 |
HIP 19744 |
8.48 |
| 2026-03-30 00:00 |
04:13:17.38 |
+42:31:56.0 |
HIP 19744 |
8.23 |
| 2026-03-30 12:00 |
04:13:19.09 |
+42:31:48.1 |
HIP 19744 |
7.99 |
| 2026-03-31 00:00 |
04:13:20.82 |
+42:31:40.3 |
HIP 19744 |
7.76 |
| 2026-03-31 12:00 |
04:13:22.57 |
+42:31:32.6 |
HIP 19744 |
7.52 |
| 2026-04-01 00:00 |
04:13:24.35 |
+42:31:25.0 |
HIP 19744 |
7.29 |
| 2026-04-01 12:00 |
04:13:26.15 |
+42:31:17.6 |
HIP 19744 |
7.07 |
| 2026-04-02 00:00 |
04:13:27.97 |
+42:31:10.2 |
HIP 19744 |
6.85 |
| 2026-04-02 12:00 |
04:13:29.82 |
+42:31:03.0 |
HIP 19744 |
6.64 |
| 2026-04-03 00:00 |
04:13:31.68 |
+42:30:55.9 |
HIP 19744 |
6.44 |
| 2026-04-03 12:00 |
04:13:33.57 |
+42:30:48.9 |
HIP 19744 |
6.25 |
| 2026-04-04 00:00 |
04:13:35.48 |
+42:30:42.0 |
HIP 19744 |
6.07 |
| 2026-04-04 12:00 |
04:13:37.41 |
+42:30:35.3 |
HIP 19744 |
5.90 |
| 2026-04-05 00:00 |
04:13:39.37 |
+42:30:28.6 |
HIP 19744 |
5.75 |
| 2026-04-05 12:00 |
04:13:41.34 |
+42:30:22.1 |
HIP 19744 |
5.62 |
| 2026-04-06 00:00 |
04:13:43.34 |
+42:30:15.7 |
HIP 19744 |
5.50 |
| 2026-04-06 12:00 |
04:13:45.36 |
+42:30:09.4 |
HIP 19744 |
5.41 |
| 2026-04-07 00:00 |
04:13:47.40 |
+42:30:03.3 |
HIP 19744 |
5.34 |
| 2026-04-07 12:00 |
04:13:49.46 |
+42:29:57.2 |
HIP 19744 |
5.29 |
| 2026-04-08 00:00 |
04:13:51.54 |
+42:29:51.3 |
HIP 19744 |
5.28 |
| 2026-04-08 12:00 |
04:13:53.64 |
+42:29:45.4 |
HIP 19744 |
5.28 |
| 2026-04-09 00:00 |
04:13:55.76 |
+42:29:39.8 |
HIP 19744 |
5.32 |
| 2026-04-09 12:00 |
04:13:57.90 |
+42:29:34.2 |
HIP 19744 |
5.38 |
| 2026-04-10 00:00 |
04:14:00.07 |
+42:29:28.7 |
HIP 19744 |
5.47 |
| 2026-04-10 12:00 |
04:14:02.25 |
+42:29:23.4 |
HIP 19744 |
5.59 |
| 2026-04-11 00:00 |
04:14:04.45 |
+42:29:18.2 |
HIP 19744 |
5.73 |
| 2026-04-11 12:00 |
04:14:06.67 |
+42:29:13.1 |
HIP 19744 |
5.90 |
| 2026-04-12 00:00 |
04:14:08.91 |
+42:29:08.1 |
HIP 19744 |
6.09 |
| 2026-04-12 12:00 |
04:14:11.17 |
+42:29:03.2 |
HIP 19744 |
6.31 |
| 2026-04-13 00:00 |
04:14:13.45 |
+42:28:58.5 |
HIP 19744 |
6.54 |
| 2026-04-13 12:00 |
04:14:15.75 |
+42:28:53.9 |
HIP 19744 |
6.79 |
| 2026-04-14 00:00 |
04:14:18.07 |
+42:28:49.4 |
HIP 19744 |
7.06 |
| 2026-04-14 12:00 |
04:14:20.40 |
+42:28:45.0 |
HIP 19744 |
7.35 |
| 2026-04-15 00:00 |
04:14:22.76 |
+42:28:40.8 |
HIP 19744 |
7.65 |
| 2026-04-15 12:00 |
04:14:25.13 |
+42:28:36.7 |
HIP 19744 |
7.96 |
| 2026-04-16 00:00 |
04:14:27.52 |
+42:28:32.7 |
HIP 19744 |
8.28 |