| Parameter |
Value |
| Designation |
C/2001 W2 (BATTERS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2001-12-23T22:02:21.914880Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:11Z |
| Obs used |
350 |
| NEO |
Yes |
| M1 |
12.100 |
| K1 |
10.750 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2001-12-05.0000000 |
| e |
0.94137478 |
| q (au) |
1.051065 |
| a (au) |
17.928550 |
| i (deg) |
115.913079 |
| Ω (om, deg) |
113.355852 |
| ω (w, deg) |
142.085792 |
| M (ma, deg) |
359.754377 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.657 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.657 |
| n |
6.000 |
| 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) |
| 2026-07-29 00:00 |
08:28:15.23 |
-19:39:55.3 |
HIP 41339 |
30.90 |
| 2026-07-29 12:00 |
08:28:18.86 |
-19:40:03.9 |
HIP 41339 |
31.77 |
| 2026-07-30 00:00 |
08:28:22.49 |
-19:40:12.7 |
HIP 41339 |
32.63 |
| 2026-07-30 12:00 |
08:28:26.12 |
-19:40:21.8 |
HIP 41339 |
33.50 |
| 2026-07-31 00:00 |
08:28:29.75 |
-19:40:31.2 |
HIP 41339 |
34.36 |
| 2026-07-31 12:00 |
08:28:33.38 |
-19:40:40.9 |
HIP 41612 |
34.71 |
| 2026-08-01 00:00 |
08:28:37.00 |
-19:40:50.8 |
HIP 41612 |
34.41 |
| 2026-08-01 12:00 |
08:28:40.62 |
-19:41:01.0 |
HIP 41612 |
34.13 |
| 2026-08-02 00:00 |
08:28:44.24 |
-19:41:11.5 |
HIP 41612 |
33.86 |
| 2026-08-02 12:00 |
08:28:47.86 |
-19:41:22.2 |
HIP 41612 |
33.61 |
| 2026-08-03 00:00 |
08:28:51.47 |
-19:41:33.3 |
HIP 41612 |
33.37 |
| 2026-08-03 12:00 |
08:28:55.08 |
-19:41:44.6 |
HIP 41612 |
33.15 |
| 2026-08-04 00:00 |
08:28:58.69 |
-19:41:56.1 |
HIP 41612 |
32.95 |
| 2026-08-04 12:00 |
08:29:02.30 |
-19:42:07.9 |
HIP 41612 |
32.76 |
| 2026-08-05 00:00 |
08:29:05.90 |
-19:42:20.0 |
HIP 41612 |
32.59 |
| 2026-08-05 12:00 |
08:29:09.49 |
-19:42:32.4 |
HIP 41612 |
32.44 |
| 2026-08-06 00:00 |
08:29:13.09 |
-19:42:45.0 |
HIP 41612 |
32.31 |
| 2026-08-06 12:00 |
08:29:16.68 |
-19:42:57.9 |
HIP 41612 |
32.20 |
| 2026-08-07 00:00 |
08:29:20.26 |
-19:43:11.0 |
HIP 41804 |
31.83 |
| 2026-08-07 12:00 |
08:29:23.84 |
-19:43:24.5 |
HIP 41804 |
31.15 |
| 2026-08-08 00:00 |
08:29:27.41 |
-19:43:38.1 |
HIP 41817 |
30.44 |
| 2026-08-08 12:00 |
08:29:30.98 |
-19:43:52.1 |
HIP 41817 |
29.71 |
| 2026-08-09 00:00 |
08:29:34.55 |
-19:44:06.3 |
HIP 41817 |
28.99 |
| 2026-08-09 12:00 |
08:29:38.10 |
-19:44:20.7 |
HIP 41817 |
28.28 |
| 2026-08-10 00:00 |
08:29:41.66 |
-19:44:35.5 |
HIP 41817 |
27.58 |
| 2026-08-10 12:00 |
08:29:45.20 |
-19:44:50.4 |
HIP 41817 |
26.90 |
| 2026-08-11 00:00 |
08:29:48.74 |
-19:45:05.7 |
HIP 41817 |
26.23 |
| 2026-08-11 12:00 |
08:29:52.27 |
-19:45:21.2 |
HIP 41817 |
25.58 |
| 2026-08-12 00:00 |
08:29:55.80 |
-19:45:36.9 |
HIP 41817 |
24.94 |
| 2026-08-12 12:00 |
08:29:59.32 |
-19:45:52.9 |
HIP 41817 |
24.32 |
| 2026-08-13 00:00 |
08:30:02.83 |
-19:46:09.1 |
HIP 41817 |
23.72 |
| 2026-08-13 12:00 |
08:30:06.33 |
-19:46:25.6 |
HIP 41817 |
23.14 |
| 2026-08-14 00:00 |
08:30:09.82 |
-19:46:42.4 |
HIP 41817 |
22.59 |
| 2026-08-14 12:00 |
08:30:13.31 |
-19:46:59.4 |
HIP 41817 |
22.05 |
| 2026-08-15 00:00 |
08:30:16.78 |
-19:47:16.6 |
HIP 41817 |
21.55 |
| 2026-08-15 12:00 |
08:30:20.25 |
-19:47:34.1 |
HIP 41817 |
21.07 |
| 2026-08-16 00:00 |
08:30:23.71 |
-19:47:51.9 |
HIP 41817 |
20.62 |
| 2026-08-16 12:00 |
08:30:27.16 |
-19:48:09.8 |
HIP 41817 |
20.20 |
| 2026-08-17 00:00 |
08:30:30.60 |
-19:48:28.1 |
HIP 41817 |
19.82 |
| 2026-08-17 12:00 |
08:30:34.03 |
-19:48:46.5 |
HIP 41817 |
19.47 |
| 2026-08-18 00:00 |
08:30:37.45 |
-19:49:05.2 |
HIP 41817 |
19.16 |
| 2026-08-18 12:00 |
08:30:40.86 |
-19:49:24.1 |
HIP 41817 |
18.89 |
| 2026-08-19 00:00 |
08:30:44.26 |
-19:49:43.3 |
HIP 41817 |
18.65 |