| 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) |
| 2026-05-12 00:00 |
09:36:28.41 |
-26:32:47.7 |
HIP 47180 |
19.48 |
| 2026-05-12 12:00 |
09:36:28.54 |
-26:32:21.5 |
HIP 47180 |
19.89 |
| 2026-05-13 00:00 |
09:36:28.69 |
-26:31:55.4 |
HIP 47180 |
20.30 |
| 2026-05-13 12:00 |
09:36:28.87 |
-26:31:29.5 |
HIP 47180 |
20.71 |
| 2026-05-14 00:00 |
09:36:29.06 |
-26:31:03.6 |
HIP 47180 |
21.11 |
| 2026-05-14 12:00 |
09:36:29.29 |
-26:30:37.8 |
HIP 47180 |
21.52 |
| 2026-05-15 00:00 |
09:36:29.53 |
-26:30:12.1 |
HIP 47180 |
21.92 |
| 2026-05-15 12:00 |
09:36:29.80 |
-26:29:46.4 |
HIP 47180 |
22.32 |
| 2026-05-16 00:00 |
09:36:30.09 |
-26:29:20.9 |
HIP 47180 |
22.72 |
| 2026-05-16 12:00 |
09:36:30.40 |
-26:28:55.5 |
HIP 47180 |
23.12 |
| 2026-05-17 00:00 |
09:36:30.74 |
-26:28:30.2 |
HIP 47180 |
23.51 |
| 2026-05-17 12:00 |
09:36:31.10 |
-26:28:05.0 |
HIP 47180 |
23.91 |
| 2026-05-18 00:00 |
09:36:31.49 |
-26:27:39.9 |
HIP 47180 |
24.30 |
| 2026-05-18 12:00 |
09:36:31.89 |
-26:27:15.0 |
HIP 47180 |
24.69 |
| 2026-05-19 00:00 |
09:36:32.32 |
-26:26:50.1 |
HIP 47180 |
25.08 |
| 2026-05-19 12:00 |
09:36:32.78 |
-26:26:25.3 |
HIP 47180 |
25.47 |
| 2026-05-20 00:00 |
09:36:33.25 |
-26:26:00.7 |
HIP 47180 |
25.85 |
| 2026-05-20 12:00 |
09:36:33.75 |
-26:25:36.1 |
HIP 47180 |
26.24 |
| 2026-05-21 00:00 |
09:36:34.27 |
-26:25:11.7 |
HIP 47180 |
26.62 |
| 2026-05-21 12:00 |
09:36:34.82 |
-26:24:47.4 |
HIP 47180 |
27.00 |
| 2026-05-22 00:00 |
09:36:35.38 |
-26:24:23.3 |
HIP 47125 |
27.25 |
| 2026-05-22 12:00 |
09:36:35.97 |
-26:23:59.2 |
HIP 47125 |
26.88 |
| 2026-05-23 00:00 |
09:36:36.58 |
-26:23:35.3 |
HIP 47125 |
26.52 |
| 2026-05-23 12:00 |
09:36:37.22 |
-26:23:11.5 |
HIP 47125 |
26.17 |
| 2026-05-24 00:00 |
09:36:37.87 |
-26:22:47.8 |
HIP 47125 |
25.82 |
| 2026-05-24 12:00 |
09:36:38.55 |
-26:22:24.2 |
HIP 47125 |
25.48 |
| 2026-05-25 00:00 |
09:36:39.25 |
-26:22:00.8 |
HIP 47125 |
25.14 |
| 2026-05-25 12:00 |
09:36:39.98 |
-26:21:37.5 |
HIP 47125 |
24.81 |
| 2026-05-26 00:00 |
09:36:40.72 |
-26:21:14.4 |
HIP 47125 |
24.48 |
| 2026-05-26 12:00 |
09:36:41.49 |
-26:20:51.4 |
HIP 47125 |
24.16 |
| 2026-05-27 00:00 |
09:36:42.28 |
-26:20:28.5 |
HIP 47125 |
23.85 |
| 2026-05-27 12:00 |
09:36:43.09 |
-26:20:05.7 |
HIP 47125 |
23.55 |
| 2026-05-28 00:00 |
09:36:43.92 |
-26:19:43.1 |
HIP 47125 |
23.25 |
| 2026-05-28 12:00 |
09:36:44.78 |
-26:19:20.6 |
HIP 47125 |
22.96 |
| 2026-05-29 00:00 |
09:36:45.66 |
-26:18:58.3 |
HIP 47125 |
22.68 |
| 2026-05-29 12:00 |
09:36:46.55 |
-26:18:36.1 |
HIP 47125 |
22.40 |
| 2026-05-30 00:00 |
09:36:47.47 |
-26:18:14.0 |
HIP 47125 |
22.14 |
| 2026-05-30 12:00 |
09:36:48.41 |
-26:17:52.1 |
HIP 47125 |
21.88 |
| 2026-05-31 00:00 |
09:36:49.38 |
-26:17:30.3 |
HIP 47125 |
21.63 |
| 2026-05-31 12:00 |
09:36:50.36 |
-26:17:08.7 |
HIP 47125 |
21.40 |
| 2026-06-01 00:00 |
09:36:51.37 |
-26:16:47.3 |
HIP 47125 |
21.17 |
| 2026-06-01 12:00 |
09:36:52.39 |
-26:16:25.9 |
HIP 47125 |
20.95 |
| 2026-06-02 00:00 |
09:36:53.44 |
-26:16:04.8 |
HIP 47125 |
20.75 |