| Parameter |
Value |
| Designation |
C/2015 K4 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2015-05-01T18:22:16.573440Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:11Z |
| Obs used |
134 |
| NEO |
- |
| M1 |
14.400 |
| K1 |
12.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2015-06-08.0000000 |
| e |
1.00011201 |
| q (au) |
2.007657 |
| a (au) |
-17923.123229 |
| i (deg) |
80.254532 |
| Ω (om, deg) |
250.771183 |
| ω (w, deg) |
357.538399 |
| M (ma, deg) |
0.000015 |
Magnitude
Scatter + Global Linear
$$
M_a = (15.431 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
15.431 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.502 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
03:41:41.23 |
+53:56:55.9 |
HIP 17200 |
6.45 |
| 2026-07-29 12:00 |
03:41:44.06 |
+53:57:30.0 |
HIP 17200 |
6.58 |
| 2026-07-30 00:00 |
03:41:46.83 |
+53:58:04.2 |
HIP 17200 |
6.76 |
| 2026-07-30 12:00 |
03:41:49.54 |
+53:58:38.4 |
HIP 17200 |
7.01 |
| 2026-07-31 00:00 |
03:41:52.21 |
+53:59:12.7 |
HIP 17200 |
7.30 |
| 2026-07-31 12:00 |
03:41:54.81 |
+53:59:46.9 |
HIP 17200 |
7.64 |
| 2026-08-01 00:00 |
03:41:57.36 |
+54:00:21.2 |
HIP 17200 |
8.01 |
| 2026-08-01 12:00 |
03:41:59.86 |
+54:00:55.5 |
HIP 17200 |
8.42 |
| 2026-08-02 00:00 |
03:42:02.30 |
+54:01:29.8 |
HIP 17200 |
8.85 |
| 2026-08-02 12:00 |
03:42:04.68 |
+54:02:04.1 |
HIP 17200 |
9.30 |
| 2026-08-03 00:00 |
03:42:07.01 |
+54:02:38.4 |
HIP 17200 |
9.76 |
| 2026-08-03 12:00 |
03:42:09.28 |
+54:03:12.7 |
HIP 17200 |
10.25 |
| 2026-08-04 00:00 |
03:42:11.50 |
+54:03:47.1 |
HIP 17200 |
10.74 |
| 2026-08-04 12:00 |
03:42:13.65 |
+54:04:21.4 |
HIP 17200 |
11.24 |
| 2026-08-05 00:00 |
03:42:15.75 |
+54:04:55.7 |
HIP 17200 |
11.75 |
| 2026-08-05 12:00 |
03:42:17.80 |
+54:05:30.0 |
HIP 17200 |
12.27 |
| 2026-08-06 00:00 |
03:42:19.78 |
+54:06:04.3 |
HIP 17200 |
12.78 |
| 2026-08-06 12:00 |
03:42:21.71 |
+54:06:38.6 |
HIP 17200 |
13.31 |
| 2026-08-07 00:00 |
03:42:23.58 |
+54:07:12.9 |
HIP 17200 |
13.83 |
| 2026-08-07 12:00 |
03:42:25.39 |
+54:07:47.2 |
HIP 17200 |
14.36 |
| 2026-08-08 00:00 |
03:42:27.14 |
+54:08:21.4 |
HIP 17200 |
14.88 |
| 2026-08-08 12:00 |
03:42:28.84 |
+54:08:55.7 |
HIP 17200 |
15.41 |
| 2026-08-09 00:00 |
03:42:30.47 |
+54:09:29.9 |
HIP 17200 |
15.94 |
| 2026-08-09 12:00 |
03:42:32.05 |
+54:10:04.1 |
HIP 17200 |
16.46 |
| 2026-08-10 00:00 |
03:42:33.56 |
+54:10:38.2 |
HIP 17200 |
16.99 |
| 2026-08-10 12:00 |
03:42:35.02 |
+54:11:12.3 |
HIP 17200 |
17.51 |
| 2026-08-11 00:00 |
03:42:36.42 |
+54:11:46.4 |
HIP 17200 |
18.03 |
| 2026-08-11 12:00 |
03:42:37.75 |
+54:12:20.5 |
HIP 17200 |
18.55 |
| 2026-08-12 00:00 |
03:42:39.03 |
+54:12:54.5 |
HIP 17200 |
19.07 |
| 2026-08-12 12:00 |
03:42:40.25 |
+54:13:28.5 |
HIP 17200 |
19.58 |
| 2026-08-13 00:00 |
03:42:41.40 |
+54:14:02.4 |
HIP 17200 |
20.09 |
| 2026-08-13 12:00 |
03:42:42.49 |
+54:14:36.3 |
HIP 17200 |
20.60 |
| 2026-08-14 00:00 |
03:42:43.53 |
+54:15:10.1 |
HIP 17200 |
21.11 |
| 2026-08-14 12:00 |
03:42:44.50 |
+54:15:43.9 |
HIP 17200 |
21.61 |
| 2026-08-15 00:00 |
03:42:45.41 |
+54:16:17.6 |
HIP 17200 |
22.11 |
| 2026-08-15 12:00 |
03:42:46.26 |
+54:16:51.3 |
HIP 17200 |
22.61 |
| 2026-08-16 00:00 |
03:42:47.05 |
+54:17:24.9 |
HIP 17200 |
23.10 |
| 2026-08-16 12:00 |
03:42:47.77 |
+54:17:58.4 |
HIP 17200 |
23.59 |
| 2026-08-17 00:00 |
03:42:48.44 |
+54:18:31.9 |
HIP 17200 |
24.08 |
| 2026-08-17 12:00 |
03:42:49.04 |
+54:19:05.3 |
HIP 17200 |
24.56 |
| 2026-08-18 00:00 |
03:42:49.58 |
+54:19:38.6 |
HIP 17200 |
25.04 |
| 2026-08-18 12:00 |
03:42:50.06 |
+54:20:11.9 |
HIP 17200 |
25.52 |
| 2026-08-19 00:00 |
03:42:50.48 |
+54:20:45.1 |
HIP 17200 |
25.99 |