| 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) |
| 2026-05-12 00:00 |
02:37:25.78 |
+60:38:42.7 |
HIP 12009 |
20.15 |
| 2026-05-12 12:00 |
02:37:35.66 |
+60:39:20.5 |
HIP 12009 |
21.49 |
| 2026-05-13 00:00 |
02:37:45.52 |
+60:39:58.6 |
HIP 12009 |
22.83 |
| 2026-05-13 12:00 |
02:37:55.37 |
+60:40:37.2 |
HIP 12293 |
23.74 |
| 2026-05-14 00:00 |
02:38:05.21 |
+60:41:16.1 |
HIP 12293 |
22.97 |
| 2026-05-14 12:00 |
02:38:15.04 |
+60:41:55.5 |
HIP 12293 |
22.25 |
| 2026-05-15 00:00 |
02:38:24.84 |
+60:42:35.4 |
HIP 12293 |
21.58 |
| 2026-05-15 12:00 |
02:38:34.64 |
+60:43:15.6 |
HIP 12293 |
20.97 |
| 2026-05-16 00:00 |
02:38:44.42 |
+60:43:56.3 |
HIP 12293 |
20.43 |
| 2026-05-16 12:00 |
02:38:54.18 |
+60:44:37.3 |
HIP 12293 |
19.96 |
| 2026-05-17 00:00 |
02:39:03.93 |
+60:45:18.8 |
HIP 12293 |
19.57 |
| 2026-05-17 12:00 |
02:39:13.65 |
+60:46:00.7 |
HIP 12293 |
19.26 |
| 2026-05-18 00:00 |
02:39:23.36 |
+60:46:43.0 |
HIP 12293 |
19.04 |
| 2026-05-18 12:00 |
02:39:33.05 |
+60:47:25.7 |
HIP 12293 |
18.91 |
| 2026-05-19 00:00 |
02:39:42.72 |
+60:48:08.7 |
HIP 12293 |
18.87 |
| 2026-05-19 12:00 |
02:39:52.37 |
+60:48:52.2 |
HIP 12293 |
18.92 |
| 2026-05-20 00:00 |
02:40:02.00 |
+60:49:36.1 |
HIP 12293 |
19.07 |
| 2026-05-20 12:00 |
02:40:11.61 |
+60:50:20.4 |
HIP 12543 |
19.30 |
| 2026-05-21 00:00 |
02:40:21.20 |
+60:51:05.1 |
HIP 12543 |
19.47 |
| 2026-05-21 12:00 |
02:40:30.76 |
+60:51:50.1 |
HIP 12543 |
19.75 |
| 2026-05-22 00:00 |
02:40:40.30 |
+60:52:35.6 |
HIP 12543 |
20.12 |
| 2026-05-22 12:00 |
02:40:49.81 |
+60:53:21.4 |
HIP 12469 |
20.52 |
| 2026-05-23 00:00 |
02:40:59.30 |
+60:54:07.6 |
HIP 12469 |
19.92 |
| 2026-05-23 12:00 |
02:41:08.77 |
+60:54:54.2 |
HIP 12469 |
19.38 |
| 2026-05-24 00:00 |
02:41:18.21 |
+60:55:41.2 |
HIP 12469 |
18.93 |
| 2026-05-24 12:00 |
02:41:27.62 |
+60:56:28.5 |
HIP 12469 |
18.56 |
| 2026-05-25 00:00 |
02:41:37.01 |
+60:57:16.2 |
HIP 12469 |
18.28 |
| 2026-05-25 12:00 |
02:41:46.37 |
+60:58:04.3 |
HIP 12469 |
18.10 |
| 2026-05-26 00:00 |
02:41:55.70 |
+60:58:52.8 |
HIP 12469 |
18.01 |
| 2026-05-26 12:00 |
02:42:05.00 |
+60:59:41.6 |
HIP 12469 |
18.03 |
| 2026-05-27 00:00 |
02:42:14.27 |
+61:00:30.7 |
HIP 12469 |
18.14 |
| 2026-05-27 12:00 |
02:42:23.52 |
+61:01:20.3 |
HIP 12469 |
18.35 |
| 2026-05-28 00:00 |
02:42:32.73 |
+61:02:10.2 |
HIP 12469 |
18.65 |
| 2026-05-28 12:00 |
02:42:41.91 |
+61:03:00.4 |
HIP 12469 |
19.04 |
| 2026-05-29 00:00 |
02:42:51.07 |
+61:03:51.0 |
HIP 12469 |
19.52 |
| 2026-05-29 12:00 |
02:43:00.19 |
+61:04:42.0 |
HIP 12469 |
20.07 |
| 2026-05-30 00:00 |
02:43:09.28 |
+61:05:33.3 |
HIP 12469 |
20.70 |
| 2026-05-30 12:00 |
02:43:18.33 |
+61:06:25.0 |
HIP 12495 |
21.26 |
| 2026-05-31 00:00 |
02:43:27.35 |
+61:07:17.0 |
HIP 12495 |
21.81 |
| 2026-05-31 12:00 |
02:43:36.34 |
+61:08:09.3 |
HIP 12817 |
21.30 |
| 2026-06-01 00:00 |
02:43:45.29 |
+61:09:02.0 |
HIP 12817 |
20.09 |
| 2026-06-01 12:00 |
02:43:54.21 |
+61:09:55.1 |
HIP 12817 |
18.91 |
| 2026-06-02 00:00 |
02:44:03.10 |
+61:10:48.4 |
HIP 12817 |
17.74 |