C/2018 E2 (Barros)
| Parameter |
Value |
| Designation |
C/2018 E2 (Barros) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2017-12-23T16:27:32.230080Z |
| Orbit solution date (soln_date, UTC) |
2022-07-06T03:12:21Z |
| Obs used |
62 |
| NEO |
- |
| M1 |
9.900 |
| K1 |
10.250 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2018-03-12T22:14:13.056000Z |
| Discovery magnitude (MPC) |
19.40 T |
| Discovery observatory (MPC) |
Y00 · SONEAR Observatory, Oliveira |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2018-03-25.0000000 |
| e |
0.99760072 |
| q (au) |
3.922284 |
| a (au) |
1634.776323 |
| i (deg) |
97.742513 |
| Ω (om, deg) |
67.202099 |
| ω (w, deg) |
277.481389 |
| M (ma, deg) |
0.001362 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.323 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.323 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.968 |
| 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) |
| 2026-02-03 00:00 |
02:14:03.77 |
+61:11:46.9 |
HIP 10224 |
18.80 |
| 2026-02-03 12:00 |
02:14:04.38 |
+61:10:51.9 |
HIP 10224 |
18.93 |
| 2026-02-04 00:00 |
02:14:05.09 |
+61:09:57.2 |
HIP 10224 |
19.12 |
| 2026-02-04 12:00 |
02:14:05.91 |
+61:09:02.8 |
HIP 10224 |
19.35 |
| 2026-02-05 00:00 |
02:14:06.83 |
+61:08:08.7 |
HIP 10224 |
19.64 |
| 2026-02-05 12:00 |
02:14:07.85 |
+61:07:15.0 |
HIP 10224 |
19.97 |
| 2026-02-06 00:00 |
02:14:08.97 |
+61:06:21.6 |
HIP 10224 |
20.35 |
| 2026-02-06 12:00 |
02:14:10.19 |
+61:05:28.5 |
HIP 10224 |
20.77 |
| 2026-02-07 00:00 |
02:14:11.52 |
+61:04:35.8 |
HIP 10224 |
21.23 |
| 2026-02-07 12:00 |
02:14:12.94 |
+61:03:43.4 |
HIP 10224 |
21.73 |
| 2026-02-08 00:00 |
02:14:14.46 |
+61:02:51.3 |
HIP 10224 |
22.26 |
| 2026-02-08 12:00 |
02:14:16.09 |
+61:01:59.6 |
HIP 10224 |
22.82 |
| 2026-02-09 00:00 |
02:14:17.81 |
+61:01:08.3 |
HIP 10585 |
23.15 |
| 2026-02-09 12:00 |
02:14:19.63 |
+61:00:17.3 |
HIP 10585 |
22.35 |
| 2026-02-10 00:00 |
02:14:21.55 |
+60:59:26.7 |
HIP 10585 |
21.56 |
| 2026-02-10 12:00 |
02:14:23.56 |
+60:58:36.5 |
HIP 10585 |
20.77 |
| 2026-02-11 00:00 |
02:14:25.67 |
+60:57:46.6 |
HIP 10585 |
19.99 |
| 2026-02-11 12:00 |
02:14:27.88 |
+60:56:57.1 |
HIP 10585 |
19.21 |
| 2026-02-12 00:00 |
02:14:30.19 |
+60:56:08.0 |
HIP 10585 |
18.43 |
| 2026-02-12 12:00 |
02:14:32.59 |
+60:55:19.3 |
HIP 10585 |
17.66 |
| 2026-02-13 00:00 |
02:14:35.09 |
+60:54:31.0 |
HIP 10585 |
16.89 |
| 2026-02-13 12:00 |
02:14:37.68 |
+60:53:43.0 |
HIP 10585 |
16.12 |
| 2026-02-14 00:00 |
02:14:40.37 |
+60:52:55.5 |
HIP 10585 |
15.36 |
| 2026-02-14 12:00 |
02:14:43.15 |
+60:52:08.3 |
HIP 10585 |
14.61 |
| 2026-02-15 00:00 |
02:14:46.02 |
+60:51:21.6 |
HIP 10585 |
13.86 |
| 2026-02-15 12:00 |
02:14:48.98 |
+60:50:35.3 |
HIP 10585 |
13.12 |
| 2026-02-16 00:00 |
02:14:52.04 |
+60:49:49.3 |
HIP 10585 |
12.39 |
| 2026-02-16 12:00 |
02:14:55.19 |
+60:49:03.8 |
HIP 10585 |
11.67 |
| 2026-02-17 00:00 |
02:14:58.43 |
+60:48:18.7 |
HIP 10585 |
10.95 |
| 2026-02-17 12:00 |
02:15:01.76 |
+60:47:34.1 |
HIP 10585 |
10.26 |
| 2026-02-18 00:00 |
02:15:05.18 |
+60:46:49.8 |
HIP 10585 |
9.58 |
| 2026-02-18 12:00 |
02:15:08.69 |
+60:46:06.0 |
HIP 10585 |
8.92 |
| 2026-02-19 00:00 |
02:15:12.29 |
+60:45:22.6 |
HIP 10585 |
8.28 |
| 2026-02-19 12:00 |
02:15:15.98 |
+60:44:39.7 |
HIP 10585 |
7.68 |
| 2026-02-20 00:00 |
02:15:19.76 |
+60:43:57.2 |
HIP 10585 |
7.11 |
| 2026-02-20 12:00 |
02:15:23.62 |
+60:43:15.1 |
HIP 10585 |
6.60 |
| 2026-02-21 00:00 |
02:15:27.57 |
+60:42:33.5 |
HIP 10585 |
6.15 |
| 2026-02-21 12:00 |
02:15:31.60 |
+60:41:52.3 |
HIP 10585 |
5.77 |
| 2026-02-22 00:00 |
02:15:35.72 |
+60:41:11.6 |
HIP 10575 |
5.11 |
| 2026-02-22 12:00 |
02:15:39.93 |
+60:40:31.3 |
HIP 10575 |
4.29 |
| 2026-02-23 00:00 |
02:15:44.22 |
+60:39:51.5 |
HIP 10575 |
3.47 |
| 2026-02-23 12:00 |
02:15:48.59 |
+60:39:12.1 |
HIP 10575 |
2.66 |
| 2026-02-24 00:00 |
02:15:53.04 |
+60:38:33.2 |
HIP 10575 |
1.87 |