| Parameter |
Value |
| Designation |
C/2021 J1 (Maury-Attard) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2021-02-19T11:39:16.738560Z |
| Orbit solution date (soln_date, UTC) |
2022-02-03T20:43:07Z |
| Obs used |
106 |
| NEO |
- |
| M1 |
17.100 |
| K1 |
5.250 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2021-04-27.0000000 |
| e |
0.93438376 |
| q (au) |
1.740634 |
| a (au) |
26.527482 |
| i (deg) |
92.719322 |
| Ω (om, deg) |
88.320215 |
| ω (w, deg) |
147.329778 |
| M (ma, deg) |
0.479817 |
Magnitude
Scatter + Global Linear
$$
M_a = (16.232 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
16.232 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.998 |
| 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 |
05:56:36.12 |
-41:30:32.0 |
HIP 28183 |
12.82 |
| 2026-05-12 12:00 |
05:56:44.60 |
-41:29:09.1 |
HIP 28183 |
10.78 |
| 2026-05-13 00:00 |
05:56:53.13 |
-41:27:47.0 |
HIP 28183 |
8.76 |
| 2026-05-13 12:00 |
05:57:01.70 |
-41:26:25.7 |
HIP 28183 |
6.81 |
| 2026-05-14 00:00 |
05:57:10.31 |
-41:25:05.1 |
HIP 28183 |
4.98 |
| 2026-05-14 12:00 |
05:57:18.97 |
-41:23:45.3 |
HIP 28183 |
3.50 |
| 2026-05-15 00:00 |
05:57:27.67 |
-41:22:26.3 |
HIP 28183 |
2.93 |
| 2026-05-15 12:00 |
05:57:36.41 |
-41:21:08.0 |
HIP 28183 |
3.71 |
| 2026-05-16 00:00 |
05:57:45.19 |
-41:19:50.5 |
HIP 28183 |
5.28 |
| 2026-05-16 12:00 |
05:57:54.02 |
-41:18:33.7 |
HIP 28183 |
7.13 |
| 2026-05-17 00:00 |
05:58:02.88 |
-41:17:17.8 |
HIP 28183 |
9.09 |
| 2026-05-17 12:00 |
05:58:11.78 |
-41:16:02.6 |
HIP 28183 |
11.10 |
| 2026-05-18 00:00 |
05:58:20.73 |
-41:14:48.2 |
HIP 28207 |
11.97 |
| 2026-05-18 12:00 |
05:58:29.71 |
-41:13:34.5 |
HIP 28207 |
12.46 |
| 2026-05-19 00:00 |
05:58:38.72 |
-41:12:21.7 |
HIP 28207 |
13.28 |
| 2026-05-19 12:00 |
05:58:47.78 |
-41:11:09.7 |
HIP 28207 |
14.37 |
| 2026-05-20 00:00 |
05:58:56.87 |
-41:09:58.4 |
HIP 28382 |
15.33 |
| 2026-05-20 12:00 |
05:59:06.00 |
-41:08:48.0 |
HIP 28382 |
13.40 |
| 2026-05-21 00:00 |
05:59:15.16 |
-41:07:38.3 |
HIP 28382 |
11.53 |
| 2026-05-21 12:00 |
05:59:24.35 |
-41:06:29.4 |
HIP 28382 |
9.76 |
| 2026-05-22 00:00 |
05:59:33.58 |
-41:05:21.4 |
HIP 28382 |
8.14 |
| 2026-05-22 12:00 |
05:59:42.84 |
-41:04:14.1 |
HIP 28382 |
6.80 |
| 2026-05-23 00:00 |
05:59:52.14 |
-41:03:07.7 |
HIP 28382 |
5.90 |
| 2026-05-23 12:00 |
06:00:01.46 |
-41:02:02.0 |
HIP 28382 |
5.68 |
| 2026-05-24 00:00 |
06:00:10.82 |
-41:00:57.1 |
HIP 28382 |
6.20 |
| 2026-05-24 12:00 |
06:00:20.21 |
-40:59:53.1 |
HIP 28382 |
7.30 |
| 2026-05-25 00:00 |
06:00:29.63 |
-40:58:49.9 |
HIP 28382 |
8.77 |
| 2026-05-25 12:00 |
06:00:39.07 |
-40:57:47.4 |
HIP 28382 |
10.45 |
| 2026-05-26 00:00 |
06:00:48.55 |
-40:56:45.8 |
HIP 28382 |
12.26 |
| 2026-05-26 12:00 |
06:00:58.05 |
-40:55:45.0 |
HIP 28382 |
14.13 |
| 2026-05-27 00:00 |
06:01:07.58 |
-40:54:45.0 |
HIP 28382 |
16.06 |
| 2026-05-27 12:00 |
06:01:17.14 |
-40:53:45.8 |
HIP 28382 |
18.02 |
| 2026-05-28 00:00 |
06:01:26.73 |
-40:52:47.4 |
HIP 28382 |
20.00 |
| 2026-05-28 12:00 |
06:01:36.34 |
-40:51:49.9 |
HIP 28631 |
21.48 |
| 2026-05-29 00:00 |
06:01:45.97 |
-40:50:53.1 |
HIP 28631 |
21.31 |
| 2026-05-29 12:00 |
06:01:55.63 |
-40:49:57.2 |
HIP 28631 |
21.33 |
| 2026-05-30 00:00 |
06:02:05.32 |
-40:49:02.1 |
HIP 28631 |
21.52 |
| 2026-05-30 12:00 |
06:02:15.03 |
-40:48:07.8 |
HIP 28631 |
21.89 |
| 2026-05-31 00:00 |
06:02:24.76 |
-40:47:14.4 |
HIP 28631 |
22.42 |
| 2026-05-31 12:00 |
06:02:34.51 |
-40:46:21.7 |
HIP 28631 |
23.11 |
| 2026-06-01 00:00 |
06:02:44.29 |
-40:45:29.9 |
HIP 28631 |
23.95 |
| 2026-06-01 12:00 |
06:02:54.08 |
-40:44:38.9 |
HIP 28631 |
24.90 |
| 2026-06-02 00:00 |
06:03:03.90 |
-40:43:48.7 |
HIP 28631 |
25.97 |