| Parameter |
Value |
| Designation |
C/1998 M2 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1998-08-13T04:08:09.286080Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:53Z |
| Obs used |
386 |
| NEO |
- |
| M1 |
8.300 |
| K1 |
11.500 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1998-08-18.0000000 |
| e |
0.99775644 |
| q (au) |
2.725333 |
| a (au) |
1214.736178 |
| i (deg) |
60.182314 |
| Ω (om, deg) |
260.880195 |
| ω (w, deg) |
37.242994 |
| M (ma, deg) |
0.000112 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.569 + 5.036\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.569 |
| n |
5.036 |
| gf |
1.000 |
| gb |
-0.500 |
| 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) |
| 2026-06-01 00:00 |
05:42:20.53 |
+14:31:06.6 |
HIP 26930 |
22.34 |
| 2026-06-01 12:00 |
05:42:22.93 |
+14:31:07.6 |
HIP 26930 |
22.12 |
| 2026-06-02 00:00 |
05:42:25.34 |
+14:31:08.6 |
HIP 26930 |
21.92 |
| 2026-06-02 12:00 |
05:42:27.75 |
+14:31:09.6 |
HIP 26930 |
21.73 |
| 2026-06-03 00:00 |
05:42:30.17 |
+14:31:10.5 |
HIP 26930 |
21.55 |
| 2026-06-03 12:00 |
05:42:32.59 |
+14:31:11.4 |
HIP 26930 |
21.39 |
| 2026-06-04 00:00 |
05:42:35.02 |
+14:31:12.2 |
HIP 26930 |
21.24 |
| 2026-06-04 12:00 |
05:42:37.45 |
+14:31:13.0 |
HIP 27022 |
21.01 |
| 2026-06-05 00:00 |
05:42:39.88 |
+14:31:13.7 |
HIP 27022 |
20.50 |
| 2026-06-05 12:00 |
05:42:42.32 |
+14:31:14.4 |
HIP 27022 |
19.98 |
| 2026-06-06 00:00 |
05:42:44.77 |
+14:31:15.0 |
HIP 27022 |
19.48 |
| 2026-06-06 12:00 |
05:42:47.21 |
+14:31:15.7 |
HIP 27022 |
18.97 |
| 2026-06-07 00:00 |
05:42:49.66 |
+14:31:16.2 |
HIP 27022 |
18.47 |
| 2026-06-07 12:00 |
05:42:52.12 |
+14:31:16.7 |
HIP 27022 |
17.98 |
| 2026-06-08 00:00 |
05:42:54.58 |
+14:31:17.2 |
HIP 27022 |
17.49 |
| 2026-06-08 12:00 |
05:42:57.04 |
+14:31:17.6 |
HIP 27022 |
17.01 |
| 2026-06-09 00:00 |
05:42:59.50 |
+14:31:18.0 |
HIP 27022 |
16.54 |
| 2026-06-09 12:00 |
05:43:01.97 |
+14:31:18.3 |
HIP 27022 |
16.07 |
| 2026-06-10 00:00 |
05:43:04.44 |
+14:31:18.6 |
HIP 27022 |
15.62 |
| 2026-06-10 12:00 |
05:43:06.91 |
+14:31:18.8 |
HIP 27022 |
15.17 |
| 2026-06-11 00:00 |
05:43:09.38 |
+14:31:19.0 |
HIP 27022 |
14.74 |
| 2026-06-11 12:00 |
05:43:11.86 |
+14:31:19.2 |
HIP 27022 |
14.31 |
| 2026-06-12 00:00 |
05:43:14.33 |
+14:31:19.3 |
HIP 27022 |
13.90 |
| 2026-06-12 12:00 |
05:43:16.81 |
+14:31:19.3 |
HIP 27022 |
13.51 |
| 2026-06-13 00:00 |
05:43:19.29 |
+14:31:19.3 |
HIP 27022 |
13.13 |
| 2026-06-13 12:00 |
05:43:21.78 |
+14:31:19.3 |
HIP 27022 |
12.76 |
| 2026-06-14 00:00 |
05:43:24.26 |
+14:31:19.2 |
HIP 27022 |
12.42 |
| 2026-06-14 12:00 |
05:43:26.75 |
+14:31:19.1 |
HIP 27022 |
12.10 |
| 2026-06-15 00:00 |
05:43:29.23 |
+14:31:18.9 |
HIP 27022 |
11.80 |
| 2026-06-15 12:00 |
05:43:31.72 |
+14:31:18.7 |
HIP 27022 |
11.52 |
| 2026-06-16 00:00 |
05:43:34.21 |
+14:31:18.4 |
HIP 27022 |
11.27 |
| 2026-06-16 12:00 |
05:43:36.69 |
+14:31:18.1 |
HIP 27022 |
11.05 |
| 2026-06-17 00:00 |
05:43:39.18 |
+14:31:17.7 |
HIP 27022 |
10.86 |
| 2026-06-17 12:00 |
05:43:41.67 |
+14:31:17.3 |
HIP 27022 |
10.69 |
| 2026-06-18 00:00 |
05:43:44.16 |
+14:31:16.8 |
HIP 27022 |
10.56 |
| 2026-06-18 12:00 |
05:43:46.65 |
+14:31:16.3 |
HIP 27022 |
10.47 |
| 2026-06-19 00:00 |
05:43:49.13 |
+14:31:15.7 |
HIP 27022 |
10.41 |
| 2026-06-19 12:00 |
05:43:51.62 |
+14:31:15.1 |
HIP 27022 |
10.38 |
| 2026-06-20 00:00 |
05:43:54.10 |
+14:31:14.4 |
HIP 27022 |
10.40 |
| 2026-06-20 12:00 |
05:43:56.59 |
+14:31:13.7 |
HIP 27022 |
10.44 |
| 2026-06-21 00:00 |
05:43:59.07 |
+14:31:13.0 |
HIP 27022 |
10.52 |
| 2026-06-21 12:00 |
05:44:01.55 |
+14:31:12.2 |
HIP 27022 |
10.64 |
| 2026-06-22 00:00 |
05:44:04.03 |
+14:31:11.3 |
HIP 27096 |
10.37 |