| Parameter |
Value |
| Designation |
C/2018 S3 (TESS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2016-06-29T12:55:24.101760Z |
| Orbit solution date (soln_date, UTC) |
2023-02-23T19:42:03Z |
| Obs used |
35 |
| NEO |
- |
| M1 |
10.400 |
| K1 |
4.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2018-09-22T09:14:41.107200Z |
| Discovery magnitude (MPC) |
18.80 G |
| Discovery observatory (MPC) |
C57 · TESS |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2017-03-08.0000000 |
| e |
1.00131593 |
| q (au) |
7.999920 |
| a (au) |
-6079.309391 |
| i (deg) |
78.418208 |
| Ω (om, deg) |
24.982385 |
| ω (w, deg) |
263.852517 |
| M (ma, deg) |
0.000523 |
Magnitude
Scatter + Global Linear
$$
M_a = (11.026 + 4.379\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
11.026 |
| n |
4.379 |
| gf |
0.999 |
| gb |
-1.000 |
| k |
0.800 |
| δ90 |
9.986 |
| 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) |
| 2026-09-20 00:00 |
01:31:51.52 |
+18:43:01.0 |
HIP 7288 |
29.13 |
| 2026-09-20 12:00 |
01:31:46.26 |
+18:42:55.1 |
HIP 7288 |
30.37 |
| 2026-09-21 00:00 |
01:31:40.98 |
+18:42:48.9 |
HIP 7288 |
31.63 |
| 2026-09-21 12:00 |
01:31:35.67 |
+18:42:42.5 |
HIP 6961 |
31.12 |
| 2026-09-22 00:00 |
01:31:30.34 |
+18:42:35.9 |
HIP 6961 |
30.03 |
| 2026-09-22 12:00 |
01:31:24.99 |
+18:42:29.0 |
HIP 6961 |
28.95 |
| 2026-09-23 00:00 |
01:31:19.61 |
+18:42:22.0 |
HIP 6961 |
27.88 |
| 2026-09-23 12:00 |
01:31:14.22 |
+18:42:14.6 |
HIP 6961 |
26.83 |
| 2026-09-24 00:00 |
01:31:08.81 |
+18:42:07.1 |
HIP 6961 |
25.80 |
| 2026-09-24 12:00 |
01:31:03.37 |
+18:41:59.3 |
HIP 6961 |
24.79 |
| 2026-09-25 00:00 |
01:30:57.91 |
+18:41:51.3 |
HIP 6961 |
23.80 |
| 2026-09-25 12:00 |
01:30:52.44 |
+18:41:43.1 |
HIP 6961 |
22.85 |
| 2026-09-26 00:00 |
01:30:46.95 |
+18:41:34.7 |
HIP 6961 |
21.93 |
| 2026-09-26 12:00 |
01:30:41.44 |
+18:41:26.0 |
HIP 6961 |
21.05 |
| 2026-09-27 00:00 |
01:30:35.91 |
+18:41:17.1 |
HIP 6961 |
20.22 |
| 2026-09-27 12:00 |
01:30:30.36 |
+18:41:08.1 |
HIP 6961 |
19.44 |
| 2026-09-28 00:00 |
01:30:24.79 |
+18:40:58.7 |
HIP 6961 |
18.72 |
| 2026-09-28 12:00 |
01:30:19.21 |
+18:40:49.2 |
HIP 6961 |
18.07 |
| 2026-09-29 00:00 |
01:30:13.61 |
+18:40:39.5 |
HIP 6961 |
17.50 |
| 2026-09-29 12:00 |
01:30:08.00 |
+18:40:29.5 |
HIP 6961 |
17.02 |
| 2026-09-30 00:00 |
01:30:02.37 |
+18:40:19.4 |
HIP 6961 |
16.63 |
| 2026-09-30 12:00 |
01:29:56.72 |
+18:40:09.0 |
HIP 6961 |
16.35 |
| 2026-10-01 00:00 |
01:29:51.06 |
+18:39:58.4 |
HIP 6961 |
16.18 |
| 2026-10-01 12:00 |
01:29:45.38 |
+18:39:47.7 |
HIP 6961 |
16.12 |
| 2026-10-02 00:00 |
01:29:39.69 |
+18:39:36.7 |
HIP 6961 |
16.18 |
| 2026-10-02 12:00 |
01:29:33.99 |
+18:39:25.5 |
HIP 6961 |
16.36 |
| 2026-10-03 00:00 |
01:29:28.28 |
+18:39:14.1 |
HIP 6961 |
16.65 |
| 2026-10-03 12:00 |
01:29:22.55 |
+18:39:02.5 |
HIP 6961 |
17.05 |
| 2026-10-04 00:00 |
01:29:16.81 |
+18:38:50.8 |
HIP 6961 |
17.55 |
| 2026-10-04 12:00 |
01:29:11.05 |
+18:38:38.8 |
HIP 6961 |
18.14 |
| 2026-10-05 00:00 |
01:29:05.29 |
+18:38:26.6 |
HIP 6961 |
18.82 |
| 2026-10-05 12:00 |
01:28:59.52 |
+18:38:14.3 |
HIP 6961 |
19.58 |
| 2026-10-06 00:00 |
01:28:53.73 |
+18:38:01.7 |
HIP 6961 |
20.41 |
| 2026-10-06 12:00 |
01:28:47.94 |
+18:37:49.0 |
HIP 6961 |
21.30 |
| 2026-10-07 00:00 |
01:28:42.13 |
+18:37:36.1 |
HIP 6961 |
22.24 |
| 2026-10-07 12:00 |
01:28:36.32 |
+18:37:23.0 |
HIP 6961 |
23.23 |
| 2026-10-08 00:00 |
01:28:30.50 |
+18:37:09.8 |
HIP 6961 |
24.27 |
| 2026-10-08 12:00 |
01:28:24.67 |
+18:36:56.3 |
HIP 6961 |
25.35 |
| 2026-10-09 00:00 |
01:28:18.83 |
+18:36:42.7 |
HIP 6961 |
26.45 |
| 2026-10-09 12:00 |
01:28:12.99 |
+18:36:28.9 |
HIP 6961 |
27.59 |
| 2026-10-10 00:00 |
01:28:07.14 |
+18:36:14.9 |
HIP 6961 |
28.75 |
| 2026-10-10 12:00 |
01:28:01.28 |
+18:36:00.8 |
HIP 6961 |
29.94 |
| 2026-10-11 00:00 |
01:27:55.42 |
+18:35:46.5 |
HIP 6722 |
30.92 |