| Parameter |
Value |
| Designation |
C/1999 K8 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2000-04-24T06:58:48.679680Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:00Z |
| Obs used |
610 |
| NEO |
- |
| M1 |
9.400 |
| K1 |
5.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2000-03-20.0000000 |
| e |
1.00071246 |
| q (au) |
4.200554 |
| a (au) |
-5895.868027 |
| i (deg) |
52.733975 |
| Ω (om, deg) |
195.394218 |
| ω (w, deg) |
164.619681 |
| M (ma, deg) |
-0.000077 |
Magnitude
Scatter + Global Linear
$$
M_a = (5.474 + 3.588\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
5.474 |
| n |
3.588 |
| gf |
0.999 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 1998-08-19 |
2000-02-01 |
+9.8022 |
-7.106 |
| 2000-05-28 |
2001-08-18 |
+4.3226 |
-3.002 |
| 2001-08-18 |
2003-03-07 |
-5.0352 |
+4.588 |
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 |
09:37:57.11 |
-27:15:41.7 |
HIP 47180 |
28.11 |
| 2026-03-26 12:00 |
09:37:55.21 |
-27:15:16.1 |
HIP 47180 |
27.53 |
| 2026-03-27 00:00 |
09:37:53.32 |
-27:14:50.5 |
HIP 47180 |
26.95 |
| 2026-03-27 12:00 |
09:37:51.45 |
-27:14:24.7 |
HIP 47180 |
26.37 |
| 2026-03-28 00:00 |
09:37:49.61 |
-27:13:58.8 |
HIP 47180 |
25.79 |
| 2026-03-28 12:00 |
09:37:47.78 |
-27:13:32.9 |
HIP 47180 |
25.22 |
| 2026-03-29 00:00 |
09:37:45.96 |
-27:13:06.8 |
HIP 47180 |
24.64 |
| 2026-03-29 12:00 |
09:37:44.17 |
-27:12:40.7 |
HIP 47180 |
24.07 |
| 2026-03-30 00:00 |
09:37:42.39 |
-27:12:14.4 |
HIP 47180 |
23.50 |
| 2026-03-30 12:00 |
09:37:40.63 |
-27:11:48.1 |
HIP 47180 |
22.93 |
| 2026-03-31 00:00 |
09:37:38.89 |
-27:11:21.7 |
HIP 47180 |
22.36 |
| 2026-03-31 12:00 |
09:37:37.17 |
-27:10:55.2 |
HIP 47180 |
21.79 |
| 2026-04-01 00:00 |
09:37:35.47 |
-27:10:28.6 |
HIP 47180 |
21.22 |
| 2026-04-01 12:00 |
09:37:33.79 |
-27:10:01.9 |
HIP 47180 |
20.66 |
| 2026-04-02 00:00 |
09:37:32.12 |
-27:09:35.2 |
HIP 47180 |
20.09 |
| 2026-04-02 12:00 |
09:37:30.48 |
-27:09:08.4 |
HIP 47180 |
19.53 |
| 2026-04-03 00:00 |
09:37:28.85 |
-27:08:41.5 |
HIP 47180 |
18.97 |
| 2026-04-03 12:00 |
09:37:27.24 |
-27:08:14.5 |
HIP 47180 |
18.42 |
| 2026-04-04 00:00 |
09:37:25.66 |
-27:07:47.5 |
HIP 47180 |
17.86 |
| 2026-04-04 12:00 |
09:37:24.09 |
-27:07:20.4 |
HIP 47180 |
17.31 |
| 2026-04-05 00:00 |
09:37:22.54 |
-27:06:53.2 |
HIP 47180 |
16.75 |
| 2026-04-05 12:00 |
09:37:21.01 |
-27:06:26.0 |
HIP 47180 |
16.20 |
| 2026-04-06 00:00 |
09:37:19.50 |
-27:05:58.7 |
HIP 47180 |
15.65 |
| 2026-04-06 12:00 |
09:37:18.01 |
-27:05:31.3 |
HIP 47180 |
15.11 |
| 2026-04-07 00:00 |
09:37:16.54 |
-27:05:03.9 |
HIP 47180 |
14.56 |
| 2026-04-07 12:00 |
09:37:15.09 |
-27:04:36.4 |
HIP 47180 |
14.02 |
| 2026-04-08 00:00 |
09:37:13.67 |
-27:04:08.9 |
HIP 47180 |
13.48 |
| 2026-04-08 12:00 |
09:37:12.26 |
-27:03:41.3 |
HIP 47180 |
12.94 |
| 2026-04-09 00:00 |
09:37:10.87 |
-27:03:13.7 |
HIP 47180 |
12.40 |
| 2026-04-09 12:00 |
09:37:09.50 |
-27:02:46.0 |
HIP 47180 |
11.87 |
| 2026-04-10 00:00 |
09:37:08.16 |
-27:02:18.3 |
HIP 47180 |
11.34 |
| 2026-04-10 12:00 |
09:37:06.83 |
-27:01:50.5 |
HIP 47180 |
10.81 |
| 2026-04-11 00:00 |
09:37:05.53 |
-27:01:22.7 |
HIP 47180 |
10.28 |
| 2026-04-11 12:00 |
09:37:04.24 |
-27:00:54.9 |
HIP 47180 |
9.76 |
| 2026-04-12 00:00 |
09:37:02.98 |
-27:00:27.0 |
HIP 47180 |
9.24 |
| 2026-04-12 12:00 |
09:37:01.74 |
-26:59:59.1 |
HIP 47180 |
8.72 |
| 2026-04-13 00:00 |
09:37:00.52 |
-26:59:31.1 |
HIP 47180 |
8.21 |
| 2026-04-13 12:00 |
09:36:59.32 |
-26:59:03.2 |
HIP 47180 |
7.70 |
| 2026-04-14 00:00 |
09:36:58.15 |
-26:58:35.1 |
HIP 47180 |
7.19 |
| 2026-04-14 12:00 |
09:36:56.99 |
-26:58:07.1 |
HIP 47180 |
6.69 |
| 2026-04-15 00:00 |
09:36:55.86 |
-26:57:39.0 |
HIP 47180 |
6.20 |
| 2026-04-15 12:00 |
09:36:54.75 |
-26:57:11.0 |
HIP 47180 |
5.71 |
| 2026-04-16 00:00 |
09:36:53.66 |
-26:56:42.9 |
HIP 47180 |
5.23 |