| Parameter |
Value |
| Designation |
C/1900 O1 (Borrelly-Brooks) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1900-08-03T16:49:18.926400Z |
| Orbit solution date (soln_date, UTC) |
2023-10-09T20:36:15Z |
| Obs used |
121 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1900-08-15.0000000 |
| e |
1.00032171 |
| q (au) |
1.014834 |
| a (au) |
-3154.489395 |
| i (deg) |
62.532910 |
| Ω (om, deg) |
329.412543 |
| ω (w, deg) |
12.422902 |
| M (ma, deg) |
0.000063 |
Magnitude
Scatter + Global Linear
$$
M_a = (8.587 + 4.390\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
8.587 |
| n |
4.390 |
| gf |
0.816 |
| gb |
-0.500 |
| k |
0.804 |
| δ90 |
1.000 |
| 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) |
| 2026-05-12 00:00 |
10:06:03.32 |
+09:15:27.9 |
HIP 49492 |
25.57 |
| 2026-05-12 12:00 |
10:06:03.20 |
+09:15:29.0 |
HIP 49492 |
25.59 |
| 2026-05-13 00:00 |
10:06:03.08 |
+09:15:30.1 |
HIP 49492 |
25.61 |
| 2026-05-13 12:00 |
10:06:02.97 |
+09:15:31.1 |
HIP 49492 |
25.63 |
| 2026-05-14 00:00 |
10:06:02.87 |
+09:15:32.0 |
HIP 49492 |
25.65 |
| 2026-05-14 12:00 |
10:06:02.78 |
+09:15:32.9 |
HIP 49492 |
25.66 |
| 2026-05-15 00:00 |
10:06:02.69 |
+09:15:33.8 |
HIP 49492 |
25.68 |
| 2026-05-15 12:00 |
10:06:02.61 |
+09:15:34.7 |
HIP 49492 |
25.70 |
| 2026-05-16 00:00 |
10:06:02.53 |
+09:15:35.5 |
HIP 49492 |
25.71 |
| 2026-05-16 12:00 |
10:06:02.46 |
+09:15:36.3 |
HIP 49492 |
25.73 |
| 2026-05-17 00:00 |
10:06:02.40 |
+09:15:37.0 |
HIP 49492 |
25.74 |
| 2026-05-17 12:00 |
10:06:02.35 |
+09:15:37.7 |
HIP 49492 |
25.76 |
| 2026-05-18 00:00 |
10:06:02.30 |
+09:15:38.4 |
HIP 49492 |
25.77 |
| 2026-05-18 12:00 |
10:06:02.26 |
+09:15:39.0 |
HIP 49492 |
25.78 |
| 2026-05-19 00:00 |
10:06:02.23 |
+09:15:39.6 |
HIP 49492 |
25.79 |
| 2026-05-19 12:00 |
10:06:02.20 |
+09:15:40.2 |
HIP 49492 |
25.80 |
| 2026-05-20 00:00 |
10:06:02.18 |
+09:15:40.7 |
HIP 49492 |
25.81 |
| 2026-05-20 12:00 |
10:06:02.17 |
+09:15:41.2 |
HIP 49492 |
25.82 |
| 2026-05-21 00:00 |
10:06:02.16 |
+09:15:41.6 |
HIP 49492 |
25.83 |
| 2026-05-21 12:00 |
10:06:02.16 |
+09:15:42.0 |
HIP 49492 |
25.83 |
| 2026-05-22 00:00 |
10:06:02.16 |
+09:15:42.4 |
HIP 49492 |
25.84 |
| 2026-05-22 12:00 |
10:06:02.18 |
+09:15:42.7 |
HIP 49492 |
25.84 |
| 2026-05-23 00:00 |
10:06:02.20 |
+09:15:43.0 |
HIP 49492 |
25.85 |
| 2026-05-23 12:00 |
10:06:02.22 |
+09:15:43.3 |
HIP 49492 |
25.85 |
| 2026-05-24 00:00 |
10:06:02.25 |
+09:15:43.5 |
HIP 49492 |
25.85 |
| 2026-05-24 12:00 |
10:06:02.29 |
+09:15:43.7 |
HIP 49492 |
25.86 |
| 2026-05-25 00:00 |
10:06:02.34 |
+09:15:43.8 |
HIP 49492 |
25.86 |
| 2026-05-25 12:00 |
10:06:02.39 |
+09:15:43.9 |
HIP 49492 |
25.86 |
| 2026-05-26 00:00 |
10:06:02.45 |
+09:15:44.0 |
HIP 49492 |
25.86 |
| 2026-05-26 12:00 |
10:06:02.52 |
+09:15:44.1 |
HIP 49492 |
25.86 |
| 2026-05-27 00:00 |
10:06:02.59 |
+09:15:44.1 |
HIP 49492 |
25.85 |
| 2026-05-27 12:00 |
10:06:02.67 |
+09:15:44.0 |
HIP 49492 |
25.85 |
| 2026-05-28 00:00 |
10:06:02.76 |
+09:15:43.9 |
HIP 49492 |
25.85 |
| 2026-05-28 12:00 |
10:06:02.85 |
+09:15:43.8 |
HIP 49492 |
25.84 |
| 2026-05-29 00:00 |
10:06:02.95 |
+09:15:43.7 |
HIP 49492 |
25.84 |
| 2026-05-29 12:00 |
10:06:03.05 |
+09:15:43.5 |
HIP 49492 |
25.83 |
| 2026-05-30 00:00 |
10:06:03.17 |
+09:15:43.3 |
HIP 49492 |
25.82 |
| 2026-05-30 12:00 |
10:06:03.28 |
+09:15:43.0 |
HIP 49492 |
25.82 |
| 2026-05-31 00:00 |
10:06:03.41 |
+09:15:42.7 |
HIP 49492 |
25.81 |
| 2026-05-31 12:00 |
10:06:03.54 |
+09:15:42.4 |
HIP 49492 |
25.80 |
| 2026-06-01 00:00 |
10:06:03.68 |
+09:15:42.0 |
HIP 49492 |
25.79 |
| 2026-06-01 12:00 |
10:06:03.82 |
+09:15:41.6 |
HIP 49492 |
25.78 |
| 2026-06-02 00:00 |
10:06:03.97 |
+09:15:41.2 |
HIP 49492 |
25.77 |