| Parameter |
Value |
| Designation |
C/2014 Y1 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2016-01-17T15:41:20.803200Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:05Z |
| Obs used |
305 |
| NEO |
- |
| M1 |
12.800 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2015-04-19.0000000 |
| e |
1.00210330 |
| q (au) |
2.240976 |
| a (au) |
-1065.459229 |
| i (deg) |
14.921289 |
| Ω (om, deg) |
19.516424 |
| ω (w, deg) |
182.265969 |
| M (ma, deg) |
-0.007755 |
Magnitude
Scatter + Global Linear
$$
M_a = (15.038 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
15.038 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.719 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2014-11-17 |
2015-04-22 |
+9.9842 |
-6.474 |
| 2015-04-22 |
2016-01-10 |
-0.5262 |
-0.311 |
| 2016-01-19 |
2016-05-29 |
+16.0709 |
-4.516 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
23:28:08.39 |
-11:55:16.1 |
HIP 115844 |
17.47 |
| 2026-03-26 12:00 |
23:28:13.00 |
-11:54:48.4 |
HIP 115844 |
17.99 |
| 2026-03-27 00:00 |
23:28:17.59 |
-11:54:20.8 |
HIP 115844 |
18.56 |
| 2026-03-27 12:00 |
23:28:22.18 |
-11:53:53.4 |
HIP 115844 |
19.20 |
| 2026-03-28 00:00 |
23:28:26.76 |
-11:53:26.1 |
HIP 115844 |
19.88 |
| 2026-03-28 12:00 |
23:28:31.32 |
-11:52:58.9 |
HIP 115844 |
20.61 |
| 2026-03-29 00:00 |
23:28:35.88 |
-11:52:31.9 |
HIP 115844 |
21.38 |
| 2026-03-29 12:00 |
23:28:40.42 |
-11:52:05.1 |
HIP 115844 |
22.19 |
| 2026-03-30 00:00 |
23:28:44.95 |
-11:51:38.4 |
HIP 115844 |
23.02 |
| 2026-03-30 12:00 |
23:28:49.47 |
-11:51:11.8 |
HIP 115844 |
23.89 |
| 2026-03-31 00:00 |
23:28:53.98 |
-11:50:45.4 |
HIP 115844 |
24.77 |
| 2026-03-31 12:00 |
23:28:58.48 |
-11:50:19.2 |
HIP 115844 |
25.68 |
| 2026-04-01 00:00 |
23:29:02.96 |
-11:49:53.1 |
HIP 115844 |
26.60 |
| 2026-04-01 12:00 |
23:29:07.44 |
-11:49:27.2 |
HIP 115839 |
27.16 |
| 2026-04-02 00:00 |
23:29:11.90 |
-11:49:01.4 |
HIP 115839 |
27.44 |
| 2026-04-02 12:00 |
23:29:16.34 |
-11:48:35.8 |
HIP 115839 |
27.77 |
| 2026-04-03 00:00 |
23:29:20.78 |
-11:48:10.3 |
HIP 115839 |
28.14 |
| 2026-04-03 12:00 |
23:29:25.20 |
-11:47:45.0 |
HIP 115839 |
28.56 |
| 2026-04-04 00:00 |
23:29:29.61 |
-11:47:19.9 |
HIP 115839 |
29.02 |
| 2026-04-04 12:00 |
23:29:34.00 |
-11:46:54.9 |
HIP 115839 |
29.51 |
| 2026-04-05 00:00 |
23:29:38.38 |
-11:46:30.1 |
HIP 115839 |
30.04 |
| 2026-04-05 12:00 |
23:29:42.74 |
-11:46:05.4 |
HIP 115839 |
30.60 |
| 2026-04-06 00:00 |
23:29:47.09 |
-11:45:40.9 |
HIP 115839 |
31.19 |
| 2026-04-06 12:00 |
23:29:51.43 |
-11:45:16.6 |
HIP 116128 |
31.48 |
| 2026-04-07 00:00 |
23:29:55.75 |
-11:44:52.5 |
HIP 116128 |
30.66 |
| 2026-04-07 12:00 |
23:30:00.05 |
-11:44:28.5 |
HIP 116128 |
29.86 |
| 2026-04-08 00:00 |
23:30:04.34 |
-11:44:04.7 |
HIP 116128 |
29.08 |
| 2026-04-08 12:00 |
23:30:08.61 |
-11:43:41.1 |
HIP 116128 |
28.32 |
| 2026-04-09 00:00 |
23:30:12.87 |
-11:43:17.7 |
HIP 116128 |
27.60 |
| 2026-04-09 12:00 |
23:30:17.11 |
-11:42:54.4 |
HIP 116128 |
26.90 |
| 2026-04-10 00:00 |
23:30:21.33 |
-11:42:31.3 |
HIP 116128 |
26.23 |
| 2026-04-10 12:00 |
23:30:25.54 |
-11:42:08.4 |
HIP 116128 |
25.59 |
| 2026-04-11 00:00 |
23:30:29.73 |
-11:41:45.7 |
HIP 116128 |
24.99 |
| 2026-04-11 12:00 |
23:30:33.90 |
-11:41:23.1 |
HIP 116128 |
24.42 |
| 2026-04-12 00:00 |
23:30:38.05 |
-11:41:00.7 |
HIP 116128 |
23.89 |
| 2026-04-12 12:00 |
23:30:42.19 |
-11:40:38.6 |
HIP 116128 |
23.40 |
| 2026-04-13 00:00 |
23:30:46.31 |
-11:40:16.6 |
HIP 116163 |
22.48 |
| 2026-04-13 12:00 |
23:30:50.41 |
-11:39:54.8 |
HIP 116163 |
21.41 |
| 2026-04-14 00:00 |
23:30:54.49 |
-11:39:33.1 |
HIP 116163 |
20.35 |
| 2026-04-14 12:00 |
23:30:58.55 |
-11:39:11.7 |
HIP 116163 |
19.29 |
| 2026-04-15 00:00 |
23:31:02.59 |
-11:38:50.5 |
HIP 116163 |
18.24 |
| 2026-04-15 12:00 |
23:31:06.61 |
-11:38:29.4 |
HIP 116163 |
17.19 |
| 2026-04-16 00:00 |
23:31:10.62 |
-11:38:08.6 |
HIP 116163 |
16.15 |