| Parameter |
Value |
| Designation |
C/1998 T1 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1999-06-25T05:58:21.192960Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:57Z |
| Obs used |
376 |
| NEO |
- |
| M1 |
12.200 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1999-05-05.0000000 |
| e |
0.99911409 |
| q (au) |
1.467728 |
| a (au) |
1656.736959 |
| i (deg) |
170.159948 |
| Ω (om, deg) |
153.357852 |
| ω (w, deg) |
226.351694 |
| M (ma, deg) |
359.999251 |
Magnitude
Scatter + Global Linear
$$
M_a = (9.231 + 4.429\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
9.231 |
| n |
4.429 |
| gf |
1.000 |
| gb |
-0.516 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
08:38:42.32 |
+23:02:04.5 |
HIP 42443 |
15.55 |
| 2026-03-26 12:00 |
08:38:40.83 |
+23:02:07.6 |
HIP 42443 |
15.76 |
| 2026-03-27 00:00 |
08:38:39.36 |
+23:02:10.6 |
HIP 42443 |
15.97 |
| 2026-03-27 12:00 |
08:38:37.91 |
+23:02:13.5 |
HIP 42443 |
16.18 |
| 2026-03-28 00:00 |
08:38:36.48 |
+23:02:16.3 |
HIP 42443 |
16.40 |
| 2026-03-28 12:00 |
08:38:35.07 |
+23:02:19.1 |
HIP 42443 |
16.61 |
| 2026-03-29 00:00 |
08:38:33.68 |
+23:02:21.8 |
HIP 42443 |
16.82 |
| 2026-03-29 12:00 |
08:38:32.31 |
+23:02:24.4 |
HIP 42443 |
17.04 |
| 2026-03-30 00:00 |
08:38:30.96 |
+23:02:26.9 |
HIP 42443 |
17.25 |
| 2026-03-30 12:00 |
08:38:29.63 |
+23:02:29.3 |
HIP 42443 |
17.46 |
| 2026-03-31 00:00 |
08:38:28.32 |
+23:02:31.6 |
HIP 42443 |
17.67 |
| 2026-03-31 12:00 |
08:38:27.02 |
+23:02:33.9 |
HIP 42443 |
17.88 |
| 2026-04-01 00:00 |
08:38:25.75 |
+23:02:36.1 |
HIP 42443 |
18.09 |
| 2026-04-01 12:00 |
08:38:24.50 |
+23:02:38.1 |
HIP 42443 |
18.30 |
| 2026-04-02 00:00 |
08:38:23.28 |
+23:02:40.1 |
HIP 42443 |
18.51 |
| 2026-04-02 12:00 |
08:38:22.07 |
+23:02:42.1 |
HIP 42443 |
18.71 |
| 2026-04-03 00:00 |
08:38:20.88 |
+23:02:43.9 |
HIP 42443 |
18.91 |
| 2026-04-03 12:00 |
08:38:19.71 |
+23:02:45.6 |
HIP 42443 |
19.11 |
| 2026-04-04 00:00 |
08:38:18.56 |
+23:02:47.3 |
HIP 42443 |
19.30 |
| 2026-04-04 12:00 |
08:38:17.44 |
+23:02:48.9 |
HIP 42443 |
19.50 |
| 2026-04-05 00:00 |
08:38:16.33 |
+23:02:50.4 |
HIP 42443 |
19.69 |
| 2026-04-05 12:00 |
08:38:15.25 |
+23:02:51.8 |
HIP 42443 |
19.88 |
| 2026-04-06 00:00 |
08:38:14.18 |
+23:02:53.1 |
HIP 42443 |
20.06 |
| 2026-04-06 12:00 |
08:38:13.14 |
+23:02:54.4 |
HIP 42443 |
20.24 |
| 2026-04-07 00:00 |
08:38:12.12 |
+23:02:55.5 |
HIP 42443 |
20.42 |
| 2026-04-07 12:00 |
08:38:11.12 |
+23:02:56.6 |
HIP 42443 |
20.60 |
| 2026-04-08 00:00 |
08:38:10.14 |
+23:02:57.6 |
HIP 42443 |
20.77 |
| 2026-04-08 12:00 |
08:38:09.18 |
+23:02:58.5 |
HIP 42253 |
20.60 |
| 2026-04-09 00:00 |
08:38:08.24 |
+23:02:59.3 |
HIP 42253 |
20.41 |
| 2026-04-09 12:00 |
08:38:07.33 |
+23:03:00.0 |
HIP 42253 |
20.24 |
| 2026-04-10 00:00 |
08:38:06.43 |
+23:03:00.7 |
HIP 42253 |
20.06 |
| 2026-04-10 12:00 |
08:38:05.56 |
+23:03:01.3 |
HIP 42253 |
19.90 |
| 2026-04-11 00:00 |
08:38:04.71 |
+23:03:01.8 |
HIP 42253 |
19.73 |
| 2026-04-11 12:00 |
08:38:03.88 |
+23:03:02.2 |
HIP 42253 |
19.58 |
| 2026-04-12 00:00 |
08:38:03.07 |
+23:03:02.5 |
HIP 42253 |
19.43 |
| 2026-04-12 12:00 |
08:38:02.28 |
+23:03:02.7 |
HIP 42253 |
19.28 |
| 2026-04-13 00:00 |
08:38:01.51 |
+23:03:02.9 |
HIP 42253 |
19.14 |
| 2026-04-13 12:00 |
08:38:00.77 |
+23:03:03.0 |
HIP 42253 |
19.00 |
| 2026-04-14 00:00 |
08:38:00.05 |
+23:03:02.9 |
HIP 42253 |
18.87 |
| 2026-04-14 12:00 |
08:37:59.35 |
+23:03:02.8 |
HIP 42253 |
18.75 |
| 2026-04-15 00:00 |
08:37:58.67 |
+23:03:02.7 |
HIP 42253 |
18.63 |
| 2026-04-15 12:00 |
08:37:58.01 |
+23:03:02.4 |
HIP 42253 |
18.52 |
| 2026-04-16 00:00 |
08:37:57.38 |
+23:03:02.1 |
HIP 42253 |
18.41 |