| Parameter |
Value |
| Designation |
C/2002 Y1 (Juels-Holvorcem) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2003-04-13T05:57:14.526720Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:25Z |
| Obs used |
760 |
| NEO |
- |
| M1 |
9.500 |
| K1 |
16.750 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2003-02-10.0000000 |
| e |
0.99715189 |
| q (au) |
0.713810 |
| a (au) |
250.625452 |
| i (deg) |
103.781543 |
| Ω (om, deg) |
166.220096 |
| ω (w, deg) |
128.815568 |
| M (ma, deg) |
359.984537 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.760 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.760 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.500 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2002-01-12 |
2003-01-11 |
-33.2594 |
+10.778 |
| 2003-01-11 |
2003-04-12 |
+5.2439 |
+0.172 |
| 2003-04-13 |
2004-01-23 |
-2.2806 |
-1.257 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
09:56:06.26 |
-58:26:01.3 |
HIP 48663 |
5.25 |
| 2026-05-12 12:00 |
09:56:05.79 |
-58:25:21.8 |
HIP 48663 |
5.20 |
| 2026-05-13 00:00 |
09:56:05.36 |
-58:24:42.4 |
HIP 48663 |
5.24 |
| 2026-05-13 12:00 |
09:56:04.98 |
-58:24:03.0 |
HIP 48663 |
5.37 |
| 2026-05-14 00:00 |
09:56:04.63 |
-58:23:23.6 |
HIP 48663 |
5.58 |
| 2026-05-14 12:00 |
09:56:04.33 |
-58:22:44.3 |
HIP 48663 |
5.85 |
| 2026-05-15 00:00 |
09:56:04.07 |
-58:22:04.9 |
HIP 48663 |
6.19 |
| 2026-05-15 12:00 |
09:56:03.85 |
-58:21:25.6 |
HIP 48663 |
6.58 |
| 2026-05-16 00:00 |
09:56:03.67 |
-58:20:46.3 |
HIP 48663 |
7.02 |
| 2026-05-16 12:00 |
09:56:03.53 |
-58:20:07.1 |
HIP 48663 |
7.49 |
| 2026-05-17 00:00 |
09:56:03.44 |
-58:19:27.9 |
HIP 48663 |
7.99 |
| 2026-05-17 12:00 |
09:56:03.38 |
-58:18:48.7 |
HIP 48663 |
8.51 |
| 2026-05-18 00:00 |
09:56:03.37 |
-58:18:09.6 |
HIP 48663 |
9.05 |
| 2026-05-18 12:00 |
09:56:03.40 |
-58:17:30.5 |
HIP 48663 |
9.61 |
| 2026-05-19 00:00 |
09:56:03.46 |
-58:16:51.5 |
HIP 48663 |
10.18 |
| 2026-05-19 12:00 |
09:56:03.57 |
-58:16:12.5 |
HIP 48663 |
10.76 |
| 2026-05-20 00:00 |
09:56:03.72 |
-58:15:33.6 |
HIP 48663 |
11.35 |
| 2026-05-20 12:00 |
09:56:03.91 |
-58:14:54.8 |
HIP 48663 |
11.95 |
| 2026-05-21 00:00 |
09:56:04.14 |
-58:14:16.0 |
HIP 48663 |
12.55 |
| 2026-05-21 12:00 |
09:56:04.42 |
-58:13:37.2 |
HIP 48663 |
13.16 |
| 2026-05-22 00:00 |
09:56:04.73 |
-58:12:58.6 |
HIP 48663 |
13.77 |
| 2026-05-22 12:00 |
09:56:05.08 |
-58:12:20.0 |
HIP 48663 |
14.39 |
| 2026-05-23 00:00 |
09:56:05.47 |
-58:11:41.4 |
HIP 48663 |
15.01 |
| 2026-05-23 12:00 |
09:56:05.91 |
-58:11:03.0 |
HIP 48663 |
15.63 |
| 2026-05-24 00:00 |
09:56:06.38 |
-58:10:24.6 |
HIP 48663 |
16.25 |
| 2026-05-24 12:00 |
09:56:06.89 |
-58:09:46.3 |
HIP 48663 |
16.88 |
| 2026-05-25 00:00 |
09:56:07.44 |
-58:09:08.1 |
HIP 48663 |
17.51 |
| 2026-05-25 12:00 |
09:56:08.03 |
-58:08:30.0 |
HIP 48663 |
18.14 |
| 2026-05-26 00:00 |
09:56:08.67 |
-58:07:52.0 |
HIP 48663 |
18.77 |
| 2026-05-26 12:00 |
09:56:09.34 |
-58:07:14.0 |
HIP 48663 |
19.40 |
| 2026-05-27 00:00 |
09:56:10.05 |
-58:06:36.2 |
HIP 48663 |
20.03 |
| 2026-05-27 12:00 |
09:56:10.80 |
-58:05:58.4 |
HIP 48663 |
20.66 |
| 2026-05-28 00:00 |
09:56:11.58 |
-58:05:20.7 |
HIP 48663 |
21.29 |
| 2026-05-28 12:00 |
09:56:12.41 |
-58:04:43.2 |
HIP 48663 |
21.92 |
| 2026-05-29 00:00 |
09:56:13.28 |
-58:04:05.7 |
HIP 48663 |
22.56 |
| 2026-05-29 12:00 |
09:56:14.18 |
-58:03:28.4 |
HIP 48617 |
22.58 |
| 2026-05-30 00:00 |
09:56:15.12 |
-58:02:51.1 |
HIP 48617 |
22.10 |
| 2026-05-30 12:00 |
09:56:16.10 |
-58:02:14.0 |
HIP 48617 |
21.63 |
| 2026-05-31 00:00 |
09:56:17.12 |
-58:01:36.9 |
HIP 48617 |
21.18 |
| 2026-05-31 12:00 |
09:56:18.18 |
-58:01:00.0 |
HIP 48617 |
20.74 |
| 2026-06-01 00:00 |
09:56:19.28 |
-58:00:23.2 |
HIP 48617 |
20.31 |
| 2026-06-01 12:00 |
09:56:20.41 |
-57:59:46.5 |
HIP 48617 |
19.90 |
| 2026-06-02 00:00 |
09:56:21.58 |
-57:59:10.0 |
HIP 48617 |
19.50 |