| Parameter |
Value |
| Designation |
C/1983 N1 (IRAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1983-05-02T16:52:11.812800Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:31Z |
| Obs used |
19 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1983-12-26.0000000 |
| e |
0.99936962 |
| q (au) |
2.418058 |
| a (au) |
3835.864208 |
| i (deg) |
138.832959 |
| Ω (om, deg) |
171.801181 |
| ω (w, deg) |
265.589825 |
| M (ma, deg) |
0.000984 |
Magnitude
Scatter + Global Linear
$$
M_a = (15.018 + 2.142\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
15.018 |
| n |
2.142 |
| gf |
1.000 |
| gb |
-0.842 |
| k |
0.800 |
| 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 |
08:27:00.58 |
+56:19:40.4 |
HIP 41544 |
19.63 |
| 2026-05-12 12:00 |
08:27:01.35 |
+56:19:24.3 |
HIP 41544 |
19.80 |
| 2026-05-13 00:00 |
08:27:02.14 |
+56:19:08.2 |
HIP 41544 |
19.97 |
| 2026-05-13 12:00 |
08:27:02.96 |
+56:18:52.2 |
HIP 41544 |
20.14 |
| 2026-05-14 00:00 |
08:27:03.81 |
+56:18:36.1 |
HIP 41544 |
20.31 |
| 2026-05-14 12:00 |
08:27:04.67 |
+56:18:20.0 |
HIP 41544 |
20.48 |
| 2026-05-15 00:00 |
08:27:05.56 |
+56:18:04.0 |
HIP 41544 |
20.66 |
| 2026-05-15 12:00 |
08:27:06.48 |
+56:17:47.9 |
HIP 41544 |
20.83 |
| 2026-05-16 00:00 |
08:27:07.42 |
+56:17:31.9 |
HIP 41544 |
21.00 |
| 2026-05-16 12:00 |
08:27:08.39 |
+56:17:15.8 |
HIP 41544 |
21.18 |
| 2026-05-17 00:00 |
08:27:09.37 |
+56:16:59.8 |
HIP 41544 |
21.36 |
| 2026-05-17 12:00 |
08:27:10.39 |
+56:16:43.8 |
HIP 41544 |
21.53 |
| 2026-05-18 00:00 |
08:27:11.42 |
+56:16:27.8 |
HIP 41544 |
21.71 |
| 2026-05-18 12:00 |
08:27:12.48 |
+56:16:11.8 |
HIP 41544 |
21.89 |
| 2026-05-19 00:00 |
08:27:13.57 |
+56:15:55.9 |
HIP 41544 |
22.07 |
| 2026-05-19 12:00 |
08:27:14.67 |
+56:15:39.9 |
HIP 41544 |
22.26 |
| 2026-05-20 00:00 |
08:27:15.80 |
+56:15:24.0 |
HIP 41544 |
22.44 |
| 2026-05-20 12:00 |
08:27:16.96 |
+56:15:08.1 |
HIP 41544 |
22.62 |
| 2026-05-21 00:00 |
08:27:18.13 |
+56:14:52.2 |
HIP 41544 |
22.81 |
| 2026-05-21 12:00 |
08:27:19.33 |
+56:14:36.3 |
HIP 41544 |
23.00 |
| 2026-05-22 00:00 |
08:27:20.55 |
+56:14:20.5 |
HIP 41544 |
23.19 |
| 2026-05-22 12:00 |
08:27:21.80 |
+56:14:04.7 |
HIP 41544 |
23.38 |
| 2026-05-23 00:00 |
08:27:23.06 |
+56:13:48.9 |
HIP 41544 |
23.57 |
| 2026-05-23 12:00 |
08:27:24.35 |
+56:13:33.1 |
HIP 41544 |
23.76 |
| 2026-05-24 00:00 |
08:27:25.67 |
+56:13:17.4 |
HIP 41544 |
23.95 |
| 2026-05-24 12:00 |
08:27:27.00 |
+56:13:01.7 |
HIP 41544 |
24.15 |
| 2026-05-25 00:00 |
08:27:28.36 |
+56:12:46.0 |
HIP 41544 |
24.34 |
| 2026-05-25 12:00 |
08:27:29.73 |
+56:12:30.4 |
HIP 41544 |
24.54 |
| 2026-05-26 00:00 |
08:27:31.13 |
+56:12:14.7 |
HIP 41544 |
24.74 |
| 2026-05-26 12:00 |
08:27:32.55 |
+56:11:59.2 |
HIP 41544 |
24.94 |
| 2026-05-27 00:00 |
08:27:34.00 |
+56:11:43.6 |
HIP 41544 |
25.14 |
| 2026-05-27 12:00 |
08:27:35.46 |
+56:11:28.1 |
HIP 41544 |
25.34 |
| 2026-05-28 00:00 |
08:27:36.95 |
+56:11:12.6 |
HIP 41544 |
25.55 |
| 2026-05-28 12:00 |
08:27:38.45 |
+56:10:57.2 |
HIP 41544 |
25.75 |
| 2026-05-29 00:00 |
08:27:39.98 |
+56:10:41.8 |
HIP 41544 |
25.96 |
| 2026-05-29 12:00 |
08:27:41.53 |
+56:10:26.4 |
HIP 41544 |
26.17 |
| 2026-05-30 00:00 |
08:27:43.10 |
+56:10:11.1 |
HIP 41544 |
26.38 |
| 2026-05-30 12:00 |
08:27:44.69 |
+56:09:55.8 |
HIP 41544 |
26.59 |
| 2026-05-31 00:00 |
08:27:46.30 |
+56:09:40.5 |
HIP 41544 |
26.80 |
| 2026-05-31 12:00 |
08:27:47.93 |
+56:09:25.3 |
HIP 41544 |
27.01 |
| 2026-06-01 00:00 |
08:27:49.58 |
+56:09:10.2 |
HIP 41544 |
27.23 |
| 2026-06-01 12:00 |
08:27:51.25 |
+56:08:55.1 |
HIP 41544 |
27.45 |
| 2026-06-02 00:00 |
08:27:52.94 |
+56:08:40.0 |
HIP 41544 |
27.66 |