| Parameter |
Value |
| Designation |
C/1998 W3 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1998-10-06T17:14:54.798720Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:57Z |
| Obs used |
162 |
| NEO |
- |
| M1 |
6.500 |
| K1 |
10.750 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1999-02-19.0000000 |
| e |
1.00089959 |
| q (au) |
4.914592 |
| a (au) |
-5463.131541 |
| i (deg) |
129.186877 |
| Ω (om, deg) |
123.916981 |
| ω (w, deg) |
6.886773 |
| M (ma, deg) |
0.000330 |
Magnitude
Scatter + Global Linear
$$
M_a = (2.412 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
2.412 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
1.000 |
| 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 |
21:21:32.46 |
+09:06:51.6 |
HIP 105364 |
18.58 |
| 2026-05-12 12:00 |
21:21:32.27 |
+09:07:04.3 |
HIP 105364 |
18.42 |
| 2026-05-13 00:00 |
21:21:32.07 |
+09:07:17.0 |
HIP 105364 |
18.26 |
| 2026-05-13 12:00 |
21:21:31.84 |
+09:07:29.5 |
HIP 105364 |
18.10 |
| 2026-05-14 00:00 |
21:21:31.60 |
+09:07:42.0 |
HIP 105364 |
17.94 |
| 2026-05-14 12:00 |
21:21:31.33 |
+09:07:54.3 |
HIP 105364 |
17.77 |
| 2026-05-15 00:00 |
21:21:31.04 |
+09:08:06.6 |
HIP 105364 |
17.60 |
| 2026-05-15 12:00 |
21:21:30.73 |
+09:08:18.8 |
HIP 105364 |
17.43 |
| 2026-05-16 00:00 |
21:21:30.41 |
+09:08:30.8 |
HIP 105364 |
17.26 |
| 2026-05-16 12:00 |
21:21:30.06 |
+09:08:42.8 |
HIP 105364 |
17.08 |
| 2026-05-17 00:00 |
21:21:29.69 |
+09:08:54.7 |
HIP 105364 |
16.90 |
| 2026-05-17 12:00 |
21:21:29.30 |
+09:09:06.4 |
HIP 105364 |
16.72 |
| 2026-05-18 00:00 |
21:21:28.89 |
+09:09:18.1 |
HIP 105364 |
16.54 |
| 2026-05-18 12:00 |
21:21:28.46 |
+09:09:29.6 |
HIP 105364 |
16.35 |
| 2026-05-19 00:00 |
21:21:28.01 |
+09:09:41.1 |
HIP 105364 |
16.17 |
| 2026-05-19 12:00 |
21:21:27.53 |
+09:09:52.4 |
HIP 105364 |
15.97 |
| 2026-05-20 00:00 |
21:21:27.04 |
+09:10:03.6 |
HIP 105364 |
15.78 |
| 2026-05-20 12:00 |
21:21:26.53 |
+09:10:14.7 |
HIP 105364 |
15.58 |
| 2026-05-21 00:00 |
21:21:26.00 |
+09:10:25.7 |
HIP 105364 |
15.38 |
| 2026-05-21 12:00 |
21:21:25.45 |
+09:10:36.6 |
HIP 105364 |
15.18 |
| 2026-05-22 00:00 |
21:21:24.87 |
+09:10:47.4 |
HIP 105364 |
14.97 |
| 2026-05-22 12:00 |
21:21:24.28 |
+09:10:58.1 |
HIP 105364 |
14.76 |
| 2026-05-23 00:00 |
21:21:23.67 |
+09:11:08.6 |
HIP 105364 |
14.55 |
| 2026-05-23 12:00 |
21:21:23.03 |
+09:11:19.0 |
HIP 105364 |
14.34 |
| 2026-05-24 00:00 |
21:21:22.38 |
+09:11:29.4 |
HIP 105364 |
14.12 |
| 2026-05-24 12:00 |
21:21:21.71 |
+09:11:39.6 |
HIP 105364 |
13.90 |
| 2026-05-25 00:00 |
21:21:21.02 |
+09:11:49.6 |
HIP 105364 |
13.67 |
| 2026-05-25 12:00 |
21:21:20.30 |
+09:11:59.6 |
HIP 105364 |
13.44 |
| 2026-05-26 00:00 |
21:21:19.57 |
+09:12:09.5 |
HIP 105364 |
13.21 |
| 2026-05-26 12:00 |
21:21:18.82 |
+09:12:19.2 |
HIP 105364 |
12.98 |
| 2026-05-27 00:00 |
21:21:18.05 |
+09:12:28.8 |
HIP 105364 |
12.74 |
| 2026-05-27 12:00 |
21:21:17.26 |
+09:12:38.3 |
HIP 105364 |
12.50 |
| 2026-05-28 00:00 |
21:21:16.45 |
+09:12:47.6 |
HIP 105364 |
12.26 |
| 2026-05-28 12:00 |
21:21:15.62 |
+09:12:56.9 |
HIP 105364 |
12.01 |
| 2026-05-29 00:00 |
21:21:14.77 |
+09:13:06.0 |
HIP 105364 |
11.76 |
| 2026-05-29 12:00 |
21:21:13.90 |
+09:13:15.0 |
HIP 105364 |
11.50 |
| 2026-05-30 00:00 |
21:21:13.01 |
+09:13:23.8 |
HIP 105364 |
11.25 |
| 2026-05-30 12:00 |
21:21:12.10 |
+09:13:32.6 |
HIP 105364 |
10.99 |
| 2026-05-31 00:00 |
21:21:11.17 |
+09:13:41.2 |
HIP 105364 |
10.72 |
| 2026-05-31 12:00 |
21:21:10.23 |
+09:13:49.7 |
HIP 105364 |
10.45 |
| 2026-06-01 00:00 |
21:21:09.26 |
+09:13:58.0 |
HIP 105364 |
10.18 |
| 2026-06-01 12:00 |
21:21:08.28 |
+09:14:06.2 |
HIP 105364 |
9.91 |
| 2026-06-02 00:00 |
21:21:07.28 |
+09:14:14.3 |
HIP 105364 |
9.63 |