C/1898 U1 (Brooks)
| Parameter |
Value |
| Designation |
C/1898 U1 (Brooks) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1898-11-23T15:38:33.040320Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:28:55Z |
| Obs used |
60 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1898-11-05.0000000 |
| e |
1.00000000 |
| q (au) |
0.756018 |
| a (au) |
- |
| i (deg) |
140.344759 |
| Ω (om, deg) |
97.741144 |
| ω (w, deg) |
123.548388 |
| M (ma, deg) |
- |
Magnitude
Scatter + Global Linear
$$
M_a = (H_0 + n\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
- |
| n |
- |
| gf |
- |
| gb |
- |
| k |
- |
| δ90 |
- |
| 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) |
| 2026-02-03 00:00 |
09:39:02.61 |
-23:44:04.7 |
HIP 47365 |
16.16 |
| 2026-02-03 12:00 |
09:39:01.73 |
-23:44:02.6 |
HIP 47365 |
16.20 |
| 2026-02-04 00:00 |
09:39:00.85 |
-23:44:00.4 |
HIP 47365 |
16.24 |
| 2026-02-04 12:00 |
09:38:59.97 |
-23:43:58.1 |
HIP 47365 |
16.28 |
| 2026-02-05 00:00 |
09:38:59.09 |
-23:43:55.8 |
HIP 47365 |
16.33 |
| 2026-02-05 12:00 |
09:38:58.21 |
-23:43:53.3 |
HIP 47365 |
16.38 |
| 2026-02-06 00:00 |
09:38:57.32 |
-23:43:50.9 |
HIP 47365 |
16.43 |
| 2026-02-06 12:00 |
09:38:56.44 |
-23:43:48.3 |
HIP 47365 |
16.49 |
| 2026-02-07 00:00 |
09:38:55.55 |
-23:43:45.7 |
HIP 47365 |
16.55 |
| 2026-02-07 12:00 |
09:38:54.67 |
-23:43:43.0 |
HIP 47365 |
16.62 |
| 2026-02-08 00:00 |
09:38:53.78 |
-23:43:40.2 |
HIP 47365 |
16.69 |
| 2026-02-08 12:00 |
09:38:52.89 |
-23:43:37.3 |
HIP 47365 |
16.76 |
| 2026-02-09 00:00 |
09:38:52.01 |
-23:43:34.4 |
HIP 47365 |
16.83 |
| 2026-02-09 12:00 |
09:38:51.12 |
-23:43:31.5 |
HIP 47365 |
16.91 |
| 2026-02-10 00:00 |
09:38:50.23 |
-23:43:28.4 |
HIP 47365 |
17.00 |
| 2026-02-10 12:00 |
09:38:49.34 |
-23:43:25.3 |
HIP 47365 |
17.08 |
| 2026-02-11 00:00 |
09:38:48.45 |
-23:43:22.1 |
HIP 47365 |
17.17 |
| 2026-02-11 12:00 |
09:38:47.56 |
-23:43:18.8 |
HIP 47365 |
17.26 |
| 2026-02-12 00:00 |
09:38:46.68 |
-23:43:15.5 |
HIP 47365 |
17.36 |
| 2026-02-12 12:00 |
09:38:45.79 |
-23:43:12.1 |
HIP 47365 |
17.46 |
| 2026-02-13 00:00 |
09:38:44.90 |
-23:43:08.6 |
HIP 47365 |
17.56 |
| 2026-02-13 12:00 |
09:38:44.01 |
-23:43:05.1 |
HIP 47365 |
17.66 |
| 2026-02-14 00:00 |
09:38:43.12 |
-23:43:01.5 |
HIP 47365 |
17.77 |
| 2026-02-14 12:00 |
09:38:42.23 |
-23:42:57.8 |
HIP 47365 |
17.88 |
| 2026-02-15 00:00 |
09:38:41.35 |
-23:42:54.1 |
HIP 47365 |
18.00 |
| 2026-02-15 12:00 |
09:38:40.46 |
-23:42:50.3 |
HIP 47365 |
18.11 |
| 2026-02-16 00:00 |
09:38:39.57 |
-23:42:46.4 |
HIP 47365 |
18.23 |
| 2026-02-16 12:00 |
09:38:38.69 |
-23:42:42.5 |
HIP 47365 |
18.35 |
| 2026-02-17 00:00 |
09:38:37.80 |
-23:42:38.5 |
HIP 47365 |
18.48 |
| 2026-02-17 12:00 |
09:38:36.92 |
-23:42:34.4 |
HIP 47365 |
18.61 |
| 2026-02-18 00:00 |
09:38:36.04 |
-23:42:30.3 |
HIP 47365 |
18.73 |
| 2026-02-18 12:00 |
09:38:35.15 |
-23:42:26.1 |
HIP 47365 |
18.87 |
| 2026-02-19 00:00 |
09:38:34.27 |
-23:42:21.8 |
HIP 47365 |
19.00 |
| 2026-02-19 12:00 |
09:38:33.39 |
-23:42:17.5 |
HIP 47365 |
19.14 |
| 2026-02-20 00:00 |
09:38:32.51 |
-23:42:13.1 |
HIP 47365 |
19.28 |
| 2026-02-20 12:00 |
09:38:31.64 |
-23:42:08.6 |
HIP 47365 |
19.42 |
| 2026-02-21 00:00 |
09:38:30.76 |
-23:42:04.1 |
HIP 47365 |
19.56 |
| 2026-02-21 12:00 |
09:38:29.88 |
-23:41:59.5 |
HIP 47365 |
19.71 |
| 2026-02-22 00:00 |
09:38:29.01 |
-23:41:54.8 |
HIP 47365 |
19.86 |
| 2026-02-22 12:00 |
09:38:28.14 |
-23:41:50.1 |
HIP 47365 |
20.01 |
| 2026-02-23 00:00 |
09:38:27.27 |
-23:41:45.4 |
HIP 47365 |
20.16 |
| 2026-02-23 12:00 |
09:38:26.40 |
-23:41:40.5 |
HIP 47365 |
20.31 |
| 2026-02-24 00:00 |
09:38:25.53 |
-23:41:35.6 |
HIP 47365 |
20.47 |