| Parameter |
Value |
| Designation |
C/1995 Q2 (Hartley-Drinkwater) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1995-08-02T17:27:23.549760Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:47Z |
| Obs used |
123 |
| NEO |
- |
| M1 |
9.700 |
| K1 |
22.000 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1995-09-06.0000000 |
| e |
0.96649288 |
| q (au) |
1.889143 |
| a (au) |
56.380355 |
| i (deg) |
168.007513 |
| Ω (om, deg) |
300.750783 |
| ω (w, deg) |
314.000279 |
| M (ma, deg) |
0.079792 |
Magnitude
Scatter + Global Linear
$$
M_a = (13.335 + 4.533\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
13.335 |
| n |
4.533 |
| gf |
1.000 |
| gb |
-0.557 |
| k |
0.869 |
| δ90 |
9.998 |
| 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 |
12:26:43.12 |
+08:37:50.8 |
HIP 60804 |
14.62 |
| 2026-07-29 12:00 |
12:26:44.11 |
+08:37:38.2 |
HIP 60804 |
14.36 |
| 2026-07-30 00:00 |
12:26:45.12 |
+08:37:25.5 |
HIP 60804 |
14.10 |
| 2026-07-30 12:00 |
12:26:46.14 |
+08:37:12.8 |
HIP 60804 |
13.84 |
| 2026-07-31 00:00 |
12:26:47.18 |
+08:37:00.0 |
HIP 60804 |
13.57 |
| 2026-07-31 12:00 |
12:26:48.23 |
+08:36:47.1 |
HIP 60804 |
13.31 |
| 2026-08-01 00:00 |
12:26:49.31 |
+08:36:34.1 |
HIP 60804 |
13.04 |
| 2026-08-01 12:00 |
12:26:50.39 |
+08:36:21.1 |
HIP 60804 |
12.78 |
| 2026-08-02 00:00 |
12:26:51.49 |
+08:36:08.0 |
HIP 60804 |
12.51 |
| 2026-08-02 12:00 |
12:26:52.61 |
+08:35:54.9 |
HIP 60804 |
12.25 |
| 2026-08-03 00:00 |
12:26:53.74 |
+08:35:41.7 |
HIP 60804 |
11.98 |
| 2026-08-03 12:00 |
12:26:54.89 |
+08:35:28.4 |
HIP 60804 |
11.72 |
| 2026-08-04 00:00 |
12:26:56.06 |
+08:35:15.1 |
HIP 60804 |
11.46 |
| 2026-08-04 12:00 |
12:26:57.24 |
+08:35:01.7 |
HIP 60804 |
11.20 |
| 2026-08-05 00:00 |
12:26:58.43 |
+08:34:48.2 |
HIP 60804 |
10.94 |
| 2026-08-05 12:00 |
12:26:59.64 |
+08:34:34.7 |
HIP 60804 |
10.69 |
| 2026-08-06 00:00 |
12:27:00.86 |
+08:34:21.2 |
HIP 60804 |
10.44 |
| 2026-08-06 12:00 |
12:27:02.10 |
+08:34:07.5 |
HIP 60804 |
10.19 |
| 2026-08-07 00:00 |
12:27:03.36 |
+08:33:53.9 |
HIP 60804 |
9.95 |
| 2026-08-07 12:00 |
12:27:04.63 |
+08:33:40.1 |
HIP 60804 |
9.72 |
| 2026-08-08 00:00 |
12:27:05.91 |
+08:33:26.3 |
HIP 60804 |
9.49 |
| 2026-08-08 12:00 |
12:27:07.21 |
+08:33:12.5 |
HIP 60804 |
9.27 |
| 2026-08-09 00:00 |
12:27:08.52 |
+08:32:58.6 |
HIP 60804 |
9.06 |
| 2026-08-09 12:00 |
12:27:09.85 |
+08:32:44.6 |
HIP 60804 |
8.86 |
| 2026-08-10 00:00 |
12:27:11.19 |
+08:32:30.7 |
HIP 60804 |
8.67 |
| 2026-08-10 12:00 |
12:27:12.55 |
+08:32:16.6 |
HIP 60804 |
8.49 |
| 2026-08-11 00:00 |
12:27:13.92 |
+08:32:02.5 |
HIP 60804 |
8.33 |
| 2026-08-11 12:00 |
12:27:15.30 |
+08:31:48.4 |
HIP 60804 |
8.18 |
| 2026-08-12 00:00 |
12:27:16.70 |
+08:31:34.2 |
HIP 60804 |
8.05 |
| 2026-08-12 12:00 |
12:27:18.11 |
+08:31:20.0 |
HIP 60804 |
7.94 |
| 2026-08-13 00:00 |
12:27:19.54 |
+08:31:05.7 |
HIP 60804 |
7.85 |
| 2026-08-13 12:00 |
12:27:20.98 |
+08:30:51.4 |
HIP 60804 |
7.77 |
| 2026-08-14 00:00 |
12:27:22.43 |
+08:30:37.0 |
HIP 60804 |
7.72 |
| 2026-08-14 12:00 |
12:27:23.90 |
+08:30:22.6 |
HIP 60804 |
7.69 |
| 2026-08-15 00:00 |
12:27:25.38 |
+08:30:08.2 |
HIP 60804 |
7.69 |
| 2026-08-15 12:00 |
12:27:26.87 |
+08:29:53.7 |
HIP 60804 |
7.71 |
| 2026-08-16 00:00 |
12:27:28.38 |
+08:29:39.2 |
HIP 60804 |
7.75 |
| 2026-08-16 12:00 |
12:27:29.89 |
+08:29:24.6 |
HIP 60804 |
7.81 |
| 2026-08-17 00:00 |
12:27:31.43 |
+08:29:10.0 |
HIP 60804 |
7.91 |
| 2026-08-17 12:00 |
12:27:32.97 |
+08:28:55.4 |
HIP 60804 |
8.02 |
| 2026-08-18 00:00 |
12:27:34.53 |
+08:28:40.8 |
HIP 60804 |
8.16 |
| 2026-08-18 12:00 |
12:27:36.09 |
+08:28:26.1 |
HIP 60804 |
8.32 |
| 2026-08-19 00:00 |
12:27:37.68 |
+08:28:11.4 |
HIP 60804 |
8.50 |