| Parameter |
Value |
| Designation |
197P/LINEAR |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2008-05-18T23:56:01.968000Z |
| Orbit solution date (soln_date, UTC) |
2023-10-20T22:43:21Z |
| Obs used |
325 |
| NEO |
Yes |
| M1 |
18.200 |
| K1 |
5.750 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2006-09-26.0000000 |
| e |
0.62994097 |
| q (au) |
1.061109 |
| a (au) |
2.867406 |
| i (deg) |
25.556064 |
| Ω (om, deg) |
66.395886 |
| ω (w, deg) |
188.752044 |
| M (ma, deg) |
238.004767 |
Magnitude
Scatter + Global Linear
$$
M_a = (20.000 + 3.258\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
20.000 |
| n |
3.258 |
| gf |
0.933 |
| gb |
-1.000 |
| k |
0.972 |
| δ90 |
4.153 |
| 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 |
07:20:59.70 |
+34:41:29.1 |
HIP 35687 |
16.13 |
| 2026-07-29 12:00 |
07:21:37.73 |
+34:41:24.6 |
HIP 35687 |
12.90 |
| 2026-07-30 00:00 |
07:22:15.75 |
+34:41:20.1 |
HIP 35687 |
13.96 |
| 2026-07-30 12:00 |
07:22:53.77 |
+34:41:15.6 |
HIP 35687 |
18.57 |
| 2026-07-31 00:00 |
07:23:31.79 |
+34:41:11.1 |
HIP 35687 |
24.84 |
| 2026-07-31 12:00 |
07:24:09.81 |
+34:41:06.7 |
HIP 35932 |
27.12 |
| 2026-08-01 00:00 |
07:24:47.82 |
+34:41:02.2 |
HIP 35932 |
27.26 |
| 2026-08-01 12:00 |
07:25:25.82 |
+34:40:57.7 |
HIP 35932 |
29.55 |
| 2026-08-02 00:00 |
07:26:03.82 |
+34:40:53.3 |
HIP 36105 |
29.99 |
| 2026-08-02 12:00 |
07:26:41.82 |
+34:40:48.9 |
HIP 36335 |
29.10 |
| 2026-08-03 00:00 |
07:27:19.81 |
+34:40:44.5 |
HIP 36335 |
22.63 |
| 2026-08-03 12:00 |
07:27:57.79 |
+34:40:40.1 |
HIP 36335 |
17.31 |
| 2026-08-04 00:00 |
07:28:35.77 |
+34:40:35.7 |
HIP 36402 |
13.00 |
| 2026-08-04 12:00 |
07:29:13.73 |
+34:40:31.4 |
HIP 36402 |
8.15 |
| 2026-08-05 00:00 |
07:29:51.69 |
+34:40:27.2 |
HIP 36402 |
9.25 |
| 2026-08-05 12:00 |
07:30:29.64 |
+34:40:23.0 |
HIP 36402 |
15.04 |
| 2026-08-06 00:00 |
07:31:07.58 |
+34:40:18.8 |
HIP 36402 |
22.10 |
| 2026-08-06 12:00 |
07:31:45.51 |
+34:40:14.7 |
HIP 36694 |
15.57 |
| 2026-08-07 00:00 |
07:32:23.43 |
+34:40:10.7 |
HIP 36694 |
9.38 |
| 2026-08-07 12:00 |
07:33:01.33 |
+34:40:06.7 |
HIP 36694 |
7.41 |
| 2026-08-08 00:00 |
07:33:39.23 |
+34:40:02.8 |
HIP 36694 |
11.97 |
| 2026-08-08 12:00 |
07:34:17.11 |
+34:39:59.0 |
HIP 36694 |
18.78 |
| 2026-08-09 00:00 |
07:34:54.97 |
+34:39:55.2 |
HIP 36904 |
24.01 |
| 2026-08-09 12:00 |
07:35:32.83 |
+34:39:51.6 |
HIP 36974 |
20.92 |
| 2026-08-10 00:00 |
07:36:10.66 |
+34:39:48.0 |
HIP 36974 |
20.24 |
| 2026-08-10 12:00 |
07:36:48.48 |
+34:39:44.5 |
HIP 36974 |
22.42 |
| 2026-08-11 00:00 |
07:37:26.29 |
+34:39:41.2 |
HIP 37177 |
16.85 |
| 2026-08-11 12:00 |
07:38:04.07 |
+34:39:38.0 |
HIP 37177 |
13.08 |
| 2026-08-12 00:00 |
07:38:41.84 |
+34:39:34.8 |
HIP 37265 |
7.33 |
| 2026-08-12 12:00 |
07:39:19.58 |
+34:39:31.8 |
HIP 37265 |
4.87 |
| 2026-08-13 00:00 |
07:39:57.31 |
+34:39:29.0 |
HIP 37397 |
9.29 |
| 2026-08-13 12:00 |
07:40:35.01 |
+34:39:26.2 |
HIP 37397 |
2.66 |
| 2026-08-14 00:00 |
07:41:12.70 |
+34:39:23.6 |
HIP 37397 |
6.93 |
| 2026-08-14 12:00 |
07:41:50.36 |
+34:39:21.2 |
HIP 37475 |
8.11 |
| 2026-08-15 00:00 |
07:42:27.99 |
+34:39:18.9 |
HIP 37475 |
13.59 |
| 2026-08-15 12:00 |
07:43:05.60 |
+34:39:16.7 |
HIP 37475 |
20.57 |
| 2026-08-16 00:00 |
07:43:43.19 |
+34:39:14.8 |
HIP 37861 |
25.03 |
| 2026-08-16 12:00 |
07:44:20.75 |
+34:39:12.9 |
HIP 37861 |
17.61 |
| 2026-08-17 00:00 |
07:44:58.29 |
+34:39:11.3 |
HIP 37861 |
10.63 |
| 2026-08-17 12:00 |
07:45:35.80 |
+34:39:09.9 |
HIP 37861 |
5.95 |
| 2026-08-18 00:00 |
07:46:13.28 |
+34:39:08.6 |
HIP 37861 |
8.77 |
| 2026-08-18 12:00 |
07:46:50.73 |
+34:39:07.5 |
HIP 37861 |
15.40 |
| 2026-08-19 00:00 |
07:47:28.15 |
+34:39:06.6 |
HIP 37980 |
19.17 |