| Parameter |
Value |
| Designation |
C/1898 F1 (Perrine) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1898-03-17T15:10:30.002880Z |
| Orbit solution date (soln_date, UTC) |
2023-10-09T20:36:13Z |
| Obs used |
327 |
| NEO |
- |
| M1 |
6.400 |
| K1 |
10.750 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1898-05-18.0000000 |
| e |
0.98044913 |
| q (au) |
1.095263 |
| a (au) |
56.021170 |
| i (deg) |
72.529160 |
| Ω (om, deg) |
263.867101 |
| ω (w, deg) |
47.308039 |
| M (ma, deg) |
0.144250 |
Magnitude
Scatter + Global Linear
$$
M_a = (H_0 + n\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
- |
| n |
- |
| gf |
- |
| gb |
- |
| k |
- |
| δ90 |
- |
| 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 |
06:29:27.82 |
-17:33:00.2 |
HIP 30836 |
13.03 |
| 2026-05-12 12:00 |
06:29:28.67 |
-17:32:52.7 |
HIP 30836 |
13.17 |
| 2026-05-13 00:00 |
06:29:29.52 |
-17:32:45.3 |
HIP 30836 |
13.32 |
| 2026-05-13 12:00 |
06:29:30.38 |
-17:32:37.9 |
HIP 30836 |
13.46 |
| 2026-05-14 00:00 |
06:29:31.24 |
-17:32:30.6 |
HIP 30836 |
13.62 |
| 2026-05-14 12:00 |
06:29:32.11 |
-17:32:23.4 |
HIP 30836 |
13.77 |
| 2026-05-15 00:00 |
06:29:32.99 |
-17:32:16.3 |
HIP 30836 |
13.94 |
| 2026-05-15 12:00 |
06:29:33.88 |
-17:32:09.2 |
HIP 30836 |
14.10 |
| 2026-05-16 00:00 |
06:29:34.77 |
-17:32:02.2 |
HIP 30836 |
14.27 |
| 2026-05-16 12:00 |
06:29:35.67 |
-17:31:55.3 |
HIP 30836 |
14.44 |
| 2026-05-17 00:00 |
06:29:36.58 |
-17:31:48.5 |
HIP 30836 |
14.62 |
| 2026-05-17 12:00 |
06:29:37.49 |
-17:31:41.7 |
HIP 30836 |
14.80 |
| 2026-05-18 00:00 |
06:29:38.41 |
-17:31:35.1 |
HIP 30836 |
14.99 |
| 2026-05-18 12:00 |
06:29:39.34 |
-17:31:28.5 |
HIP 30836 |
15.18 |
| 2026-05-19 00:00 |
06:29:40.27 |
-17:31:21.9 |
HIP 30836 |
15.37 |
| 2026-05-19 12:00 |
06:29:41.21 |
-17:31:15.5 |
HIP 30836 |
15.57 |
| 2026-05-20 00:00 |
06:29:42.16 |
-17:31:09.1 |
HIP 30836 |
15.76 |
| 2026-05-20 12:00 |
06:29:43.11 |
-17:31:02.9 |
HIP 30836 |
15.97 |
| 2026-05-21 00:00 |
06:29:44.07 |
-17:30:56.6 |
HIP 30836 |
16.17 |
| 2026-05-21 12:00 |
06:29:45.03 |
-17:30:50.5 |
HIP 30836 |
16.38 |
| 2026-05-22 00:00 |
06:29:46.00 |
-17:30:44.5 |
HIP 30836 |
16.59 |
| 2026-05-22 12:00 |
06:29:46.98 |
-17:30:38.5 |
HIP 30836 |
16.80 |
| 2026-05-23 00:00 |
06:29:47.96 |
-17:30:32.7 |
HIP 30836 |
17.02 |
| 2026-05-23 12:00 |
06:29:48.95 |
-17:30:26.9 |
HIP 30836 |
17.24 |
| 2026-05-24 00:00 |
06:29:49.94 |
-17:30:21.2 |
HIP 30836 |
17.46 |
| 2026-05-24 12:00 |
06:29:50.94 |
-17:30:15.5 |
HIP 30836 |
17.68 |
| 2026-05-25 00:00 |
06:29:51.95 |
-17:30:10.0 |
HIP 30836 |
17.91 |
| 2026-05-25 12:00 |
06:29:52.96 |
-17:30:04.5 |
HIP 30836 |
18.14 |
| 2026-05-26 00:00 |
06:29:53.97 |
-17:29:59.1 |
HIP 30836 |
18.37 |
| 2026-05-26 12:00 |
06:29:54.99 |
-17:29:53.8 |
HIP 30836 |
18.60 |
| 2026-05-27 00:00 |
06:29:56.02 |
-17:29:48.6 |
HIP 30836 |
18.84 |
| 2026-05-27 12:00 |
06:29:57.05 |
-17:29:43.5 |
HIP 30836 |
19.07 |
| 2026-05-28 00:00 |
06:29:58.09 |
-17:29:38.5 |
HIP 30836 |
19.31 |
| 2026-05-28 12:00 |
06:29:59.13 |
-17:29:33.5 |
HIP 30836 |
19.55 |
| 2026-05-29 00:00 |
06:30:00.18 |
-17:29:28.7 |
HIP 30836 |
19.79 |
| 2026-05-29 12:00 |
06:30:01.23 |
-17:29:23.9 |
HIP 30836 |
20.04 |
| 2026-05-30 00:00 |
06:30:02.28 |
-17:29:19.2 |
HIP 30836 |
20.28 |
| 2026-05-30 12:00 |
06:30:03.34 |
-17:29:14.6 |
HIP 30836 |
20.53 |
| 2026-05-31 00:00 |
06:30:04.41 |
-17:29:10.0 |
HIP 30836 |
20.78 |
| 2026-05-31 12:00 |
06:30:05.48 |
-17:29:05.6 |
HIP 30836 |
21.03 |
| 2026-06-01 00:00 |
06:30:06.56 |
-17:29:01.2 |
HIP 30836 |
21.28 |
| 2026-06-01 12:00 |
06:30:07.64 |
-17:28:57.0 |
HIP 30836 |
21.54 |
| 2026-06-02 00:00 |
06:30:08.72 |
-17:28:52.8 |
HIP 30836 |
21.79 |