| Parameter |
Value |
| Designation |
C/2013 X1 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2016-04-20T17:29:19.973760Z |
| Orbit solution date (soln_date, UTC) |
2022-10-25T15:34:16Z |
| Obs used |
539 |
| NEO |
- |
| M1 |
10.700 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2015-12-20.0000000 |
| e |
1.00102603 |
| q (au) |
1.314236 |
| a (au) |
-1280.894658 |
| i (deg) |
163.231932 |
| Ω (om, deg) |
130.954864 |
| ω (w, deg) |
164.460665 |
| M (ma, deg) |
-0.002639 |
Magnitude
Scatter + Global Linear
$$
M_a = (9.099 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
9.099 |
| n |
2.000 |
| gf |
0.800 |
| gb |
-0.500 |
| k |
1.000 |
| δ90 |
8.071 |
| 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 |
| 2013-10-17 |
2015-12-16 |
-0.6279 |
-0.078 |
| 2015-12-16 |
2016-01-10 |
+25.7145 |
-8.967 |
| 2016-01-10 |
2016-04-20 |
+10.9709 |
-4.036 |
| 2016-04-22 |
2018-01-29 |
+6.2799 |
-3.384 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
11:03:49.64 |
-06:02:48.1 |
HIP 53995 |
26.15 |
| 2026-06-01 12:00 |
11:03:49.07 |
-06:02:28.8 |
HIP 53995 |
26.32 |
| 2026-06-02 00:00 |
11:03:48.54 |
-06:02:09.7 |
HIP 53995 |
26.50 |
| 2026-06-02 12:00 |
11:03:48.05 |
-06:01:50.9 |
HIP 53995 |
26.68 |
| 2026-06-03 00:00 |
11:03:47.60 |
-06:01:32.3 |
HIP 53995 |
26.87 |
| 2026-06-03 12:00 |
11:03:47.18 |
-06:01:13.9 |
HIP 53995 |
27.07 |
| 2026-06-04 00:00 |
11:03:46.80 |
-06:00:55.8 |
HIP 53995 |
27.26 |
| 2026-06-04 12:00 |
11:03:46.45 |
-06:00:37.8 |
HIP 53995 |
27.47 |
| 2026-06-05 00:00 |
11:03:46.15 |
-06:00:20.2 |
HIP 53995 |
27.67 |
| 2026-06-05 12:00 |
11:03:45.88 |
-06:00:02.7 |
HIP 53995 |
27.88 |
| 2026-06-06 00:00 |
11:03:45.64 |
-05:59:45.5 |
HIP 53995 |
28.09 |
| 2026-06-06 12:00 |
11:03:45.44 |
-05:59:28.6 |
HIP 53995 |
28.31 |
| 2026-06-07 00:00 |
11:03:45.28 |
-05:59:11.8 |
HIP 53995 |
28.53 |
| 2026-06-07 12:00 |
11:03:45.16 |
-05:58:55.4 |
HIP 53995 |
28.75 |
| 2026-06-08 00:00 |
11:03:45.07 |
-05:58:39.1 |
HIP 53995 |
28.97 |
| 2026-06-08 12:00 |
11:03:45.02 |
-05:58:23.1 |
HIP 53995 |
29.19 |
| 2026-06-09 00:00 |
11:03:45.01 |
-05:58:07.3 |
HIP 53995 |
29.42 |
| 2026-06-09 12:00 |
11:03:45.03 |
-05:57:51.8 |
HIP 53995 |
29.64 |
| 2026-06-10 00:00 |
11:03:45.09 |
-05:57:36.5 |
HIP 53995 |
29.87 |
| 2026-06-10 12:00 |
11:03:45.19 |
-05:57:21.5 |
HIP 53995 |
30.10 |
| 2026-06-11 00:00 |
11:03:45.32 |
-05:57:06.7 |
HIP 53995 |
30.33 |
| 2026-06-11 12:00 |
11:03:45.49 |
-05:56:52.2 |
HIP 53995 |
30.57 |
| 2026-06-12 00:00 |
11:03:45.69 |
-05:56:37.9 |
HIP 53995 |
30.80 |
| 2026-06-12 12:00 |
11:03:45.93 |
-05:56:23.8 |
HIP 53995 |
31.03 |
| 2026-06-13 00:00 |
11:03:46.21 |
-05:56:10.0 |
HIP 53995 |
31.27 |
| 2026-06-13 12:00 |
11:03:46.52 |
-05:55:56.5 |
HIP 53995 |
31.50 |
| 2026-06-14 00:00 |
11:03:46.87 |
-05:55:43.1 |
HIP 53995 |
31.74 |
| 2026-06-14 12:00 |
11:03:47.26 |
-05:55:30.1 |
HIP 53995 |
31.98 |
| 2026-06-15 00:00 |
11:03:47.68 |
-05:55:17.3 |
HIP 53995 |
32.22 |
| 2026-06-15 12:00 |
11:03:48.13 |
-05:55:04.7 |
HIP 53995 |
32.45 |
| 2026-06-16 00:00 |
11:03:48.63 |
-05:54:52.4 |
HIP 53995 |
32.69 |
| 2026-06-16 12:00 |
11:03:49.15 |
-05:54:40.4 |
HIP 54121 |
32.54 |
| 2026-06-17 00:00 |
11:03:49.72 |
-05:54:28.5 |
HIP 54121 |
32.32 |
| 2026-06-17 12:00 |
11:03:50.31 |
-05:54:17.0 |
HIP 54121 |
32.09 |
| 2026-06-18 00:00 |
11:03:50.95 |
-05:54:05.7 |
HIP 54121 |
31.87 |
| 2026-06-18 12:00 |
11:03:51.62 |
-05:53:54.6 |
HIP 54121 |
31.64 |
| 2026-06-19 00:00 |
11:03:52.32 |
-05:53:43.8 |
HIP 54121 |
31.42 |
| 2026-06-19 12:00 |
11:03:53.06 |
-05:53:33.3 |
HIP 54121 |
31.21 |
| 2026-06-20 00:00 |
11:03:53.83 |
-05:53:23.0 |
HIP 54121 |
30.99 |
| 2026-06-20 12:00 |
11:03:54.64 |
-05:53:13.0 |
HIP 54121 |
30.78 |
| 2026-06-21 00:00 |
11:03:55.48 |
-05:53:03.2 |
HIP 54121 |
30.57 |
| 2026-06-21 12:00 |
11:03:56.35 |
-05:52:53.6 |
HIP 54121 |
30.36 |
| 2026-06-22 00:00 |
11:03:57.26 |
-05:52:44.3 |
HIP 54121 |
30.16 |