| Parameter |
Value |
| Designation |
C/1980 V1 (Meier) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1980-12-09T15:31:46.606080Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:29Z |
| Obs used |
61 |
| NEO |
- |
| M1 |
7.200 |
| K1 |
10.250 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1981-01-14.0000000 |
| e |
0.99459747 |
| q (au) |
1.519494 |
| a (au) |
281.256043 |
| i (deg) |
100.985508 |
| Ω (om, deg) |
25.436876 |
| ω (w, deg) |
87.964495 |
| M (ma, deg) |
0.007387 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.541 + 3.275\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.541 |
| n |
3.275 |
| gf |
0.800 |
| gb |
-0.500 |
| k |
1.000 |
| δ90 |
1.000 |
| 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 |
08:42:50.46 |
-57:14:55.0 |
HIP 42749 |
2.86 |
| 2026-05-12 12:00 |
08:42:51.03 |
-57:14:31.0 |
HIP 42749 |
2.50 |
| 2026-05-13 00:00 |
08:42:51.63 |
-57:14:07.0 |
HIP 42749 |
2.16 |
| 2026-05-13 12:00 |
08:42:52.26 |
-57:13:43.1 |
HIP 42749 |
1.85 |
| 2026-05-14 00:00 |
08:42:52.91 |
-57:13:19.2 |
HIP 42749 |
1.59 |
| 2026-05-14 12:00 |
08:42:53.58 |
-57:12:55.4 |
HIP 42749 |
1.40 |
| 2026-05-15 00:00 |
08:42:54.28 |
-57:12:31.7 |
HIP 42749 |
1.32 |
| 2026-05-15 12:00 |
08:42:55.01 |
-57:12:08.1 |
HIP 42749 |
1.36 |
| 2026-05-16 00:00 |
08:42:55.76 |
-57:11:44.5 |
HIP 42749 |
1.52 |
| 2026-05-16 12:00 |
08:42:56.53 |
-57:11:21.1 |
HIP 42749 |
1.76 |
| 2026-05-17 00:00 |
08:42:57.33 |
-57:10:57.7 |
HIP 42749 |
2.06 |
| 2026-05-17 12:00 |
08:42:58.16 |
-57:10:34.3 |
HIP 42749 |
2.39 |
| 2026-05-18 00:00 |
08:42:59.01 |
-57:10:11.1 |
HIP 42749 |
2.74 |
| 2026-05-18 12:00 |
08:42:59.88 |
-57:09:47.9 |
HIP 42749 |
3.11 |
| 2026-05-19 00:00 |
08:43:00.78 |
-57:09:24.9 |
HIP 42749 |
3.48 |
| 2026-05-19 12:00 |
08:43:01.70 |
-57:09:01.9 |
HIP 42749 |
3.86 |
| 2026-05-20 00:00 |
08:43:02.65 |
-57:08:39.0 |
HIP 42749 |
4.25 |
| 2026-05-20 12:00 |
08:43:03.62 |
-57:08:16.2 |
HIP 42749 |
4.64 |
| 2026-05-21 00:00 |
08:43:04.61 |
-57:07:53.5 |
HIP 42749 |
5.03 |
| 2026-05-21 12:00 |
08:43:05.63 |
-57:07:30.9 |
HIP 42749 |
5.42 |
| 2026-05-22 00:00 |
08:43:06.67 |
-57:07:08.4 |
HIP 42749 |
5.82 |
| 2026-05-22 12:00 |
08:43:07.74 |
-57:06:45.9 |
HIP 42749 |
6.21 |
| 2026-05-23 00:00 |
08:43:08.83 |
-57:06:23.6 |
HIP 42749 |
6.61 |
| 2026-05-23 12:00 |
08:43:09.94 |
-57:06:01.4 |
HIP 42749 |
7.01 |
| 2026-05-24 00:00 |
08:43:11.08 |
-57:05:39.3 |
HIP 42749 |
7.40 |
| 2026-05-24 12:00 |
08:43:12.24 |
-57:05:17.2 |
HIP 42749 |
7.80 |
| 2026-05-25 00:00 |
08:43:13.42 |
-57:04:55.3 |
HIP 42749 |
8.20 |
| 2026-05-25 12:00 |
08:43:14.62 |
-57:04:33.5 |
HIP 42749 |
8.60 |
| 2026-05-26 00:00 |
08:43:15.85 |
-57:04:11.8 |
HIP 42749 |
8.99 |
| 2026-05-26 12:00 |
08:43:17.10 |
-57:03:50.2 |
HIP 42749 |
9.39 |
| 2026-05-27 00:00 |
08:43:18.37 |
-57:03:28.7 |
HIP 42749 |
9.79 |
| 2026-05-27 12:00 |
08:43:19.67 |
-57:03:07.4 |
HIP 42749 |
10.19 |
| 2026-05-28 00:00 |
08:43:20.99 |
-57:02:46.1 |
HIP 42749 |
10.58 |
| 2026-05-28 12:00 |
08:43:22.32 |
-57:02:25.0 |
HIP 42749 |
10.98 |
| 2026-05-29 00:00 |
08:43:23.69 |
-57:02:03.9 |
HIP 42749 |
11.38 |
| 2026-05-29 12:00 |
08:43:25.07 |
-57:01:43.0 |
HIP 42749 |
11.77 |
| 2026-05-30 00:00 |
08:43:26.48 |
-57:01:22.2 |
HIP 42749 |
12.17 |
| 2026-05-30 12:00 |
08:43:27.90 |
-57:01:01.5 |
HIP 42749 |
12.56 |
| 2026-05-31 00:00 |
08:43:29.35 |
-57:00:41.0 |
HIP 42749 |
12.96 |
| 2026-05-31 12:00 |
08:43:30.82 |
-57:00:20.6 |
HIP 42749 |
13.35 |
| 2026-06-01 00:00 |
08:43:32.31 |
-57:00:00.2 |
HIP 42749 |
13.75 |
| 2026-06-01 12:00 |
08:43:33.82 |
-56:59:40.1 |
HIP 42749 |
14.14 |
| 2026-06-02 00:00 |
08:43:35.36 |
-56:59:20.0 |
HIP 42749 |
14.54 |