| Parameter |
Value |
| Designation |
C/2023 B2 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2023-03-10T11:54:03.790080Z |
| Orbit solution date (soln_date, UTC) |
2023-12-12T20:44:25Z |
| Obs used |
1107 |
| NEO |
- |
| M1 |
5.800 |
| K1 |
34.500 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2023-01-21T23:14:22.070400Z |
| Discovery magnitude (MPC) |
18.82 c |
| Discovery observatory (MPC) |
M22 · ATLAS South Africa, Sutherland |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2023-04-20.0000000 |
| e |
0.99712391 |
| q (au) |
1.743129 |
| a (au) |
606.075015 |
| i (deg) |
40.770763 |
| Ω (om, deg) |
218.120594 |
| ω (w, deg) |
317.399433 |
| M (ma, deg) |
0.002676 |
Magnitude
Scatter + Global Linear
$$
M_a = (13.836 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
13.836 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-1.000 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2022-11-16 |
2023-03-09 |
+18.9790 |
-4.051 |
| 2023-03-11 |
2023-05-22 |
+44.4170 |
-11.509 |
| 2023-05-22 |
2023-07-17 |
-28.8936 |
+9.864 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-09-25 00:00 |
19:48:46.19 |
+22:33:04.6 |
HIP 97474 |
5.70 |
| 2026-09-25 12:00 |
19:48:44.00 |
+22:31:21.6 |
HIP 97474 |
7.36 |
| 2026-09-26 00:00 |
19:48:41.90 |
+22:29:38.5 |
HIP 97474 |
9.06 |
| 2026-09-26 12:00 |
19:48:39.89 |
+22:27:55.4 |
HIP 97474 |
10.80 |
| 2026-09-27 00:00 |
19:48:37.98 |
+22:26:12.3 |
HIP 97474 |
12.54 |
| 2026-09-27 12:00 |
19:48:36.16 |
+22:24:29.1 |
HIP 97413 |
14.06 |
| 2026-09-28 00:00 |
19:48:34.43 |
+22:22:45.9 |
HIP 97413 |
12.54 |
| 2026-09-28 12:00 |
19:48:32.80 |
+22:21:02.7 |
HIP 97413 |
11.12 |
| 2026-09-29 00:00 |
19:48:31.25 |
+22:19:19.6 |
HIP 97413 |
9.81 |
| 2026-09-29 12:00 |
19:48:29.81 |
+22:17:36.4 |
HIP 97413 |
8.69 |
| 2026-09-30 00:00 |
19:48:28.45 |
+22:15:53.3 |
HIP 97413 |
7.83 |
| 2026-09-30 12:00 |
19:48:27.19 |
+22:14:10.1 |
HIP 97413 |
7.31 |
| 2026-10-01 00:00 |
19:48:26.02 |
+22:12:27.1 |
HIP 97413 |
7.21 |
| 2026-10-01 12:00 |
19:48:24.95 |
+22:10:44.0 |
HIP 97413 |
7.54 |
| 2026-10-02 00:00 |
19:48:23.96 |
+22:09:01.0 |
HIP 97413 |
8.24 |
| 2026-10-02 12:00 |
19:48:23.08 |
+22:07:18.1 |
HIP 97471 |
9.20 |
| 2026-10-03 00:00 |
19:48:22.28 |
+22:05:35.3 |
HIP 97471 |
7.81 |
| 2026-10-03 12:00 |
19:48:21.58 |
+22:03:52.5 |
HIP 97471 |
6.57 |
| 2026-10-04 00:00 |
19:48:20.97 |
+22:02:09.8 |
HIP 97471 |
5.57 |
| 2026-10-04 12:00 |
19:48:20.46 |
+22:00:27.2 |
HIP 97471 |
4.95 |
| 2026-10-05 00:00 |
19:48:20.04 |
+21:58:44.7 |
HIP 97471 |
4.87 |
| 2026-10-05 12:00 |
19:48:19.71 |
+21:57:02.4 |
HIP 97471 |
5.35 |
| 2026-10-06 00:00 |
19:48:19.48 |
+21:55:20.1 |
HIP 97471 |
6.24 |
| 2026-10-06 12:00 |
19:48:19.34 |
+21:53:38.0 |
HIP 97471 |
7.42 |
| 2026-10-07 00:00 |
19:48:19.29 |
+21:51:56.0 |
HIP 97471 |
8.75 |
| 2026-10-07 12:00 |
19:48:19.34 |
+21:50:14.2 |
HIP 97471 |
10.18 |
| 2026-10-08 00:00 |
19:48:19.48 |
+21:48:32.5 |
HIP 97471 |
11.67 |
| 2026-10-08 12:00 |
19:48:19.71 |
+21:46:51.0 |
HIP 97471 |
13.20 |
| 2026-10-09 00:00 |
19:48:20.04 |
+21:45:09.7 |
HIP 97359 |
14.33 |
| 2026-10-09 12:00 |
19:48:20.46 |
+21:43:28.5 |
HIP 97359 |
14.65 |
| 2026-10-10 00:00 |
19:48:20.98 |
+21:41:47.6 |
HIP 97359 |
15.18 |
| 2026-10-10 12:00 |
19:48:21.58 |
+21:40:06.8 |
HIP 97359 |
15.89 |
| 2026-10-11 00:00 |
19:48:22.28 |
+21:38:26.2 |
HIP 97442 |
15.92 |
| 2026-10-11 12:00 |
19:48:23.08 |
+21:36:45.9 |
HIP 97442 |
14.27 |
| 2026-10-12 00:00 |
19:48:23.96 |
+21:35:05.8 |
HIP 97442 |
12.63 |
| 2026-10-12 12:00 |
19:48:24.94 |
+21:33:25.9 |
HIP 97442 |
11.01 |
| 2026-10-13 00:00 |
19:48:26.01 |
+21:31:46.3 |
HIP 97442 |
9.41 |
| 2026-10-13 12:00 |
19:48:27.18 |
+21:30:06.9 |
HIP 97442 |
7.87 |
| 2026-10-14 00:00 |
19:48:28.43 |
+21:28:27.8 |
HIP 97442 |
6.40 |
| 2026-10-14 12:00 |
19:48:29.78 |
+21:26:49.0 |
HIP 97442 |
5.08 |
| 2026-10-15 00:00 |
19:48:31.21 |
+21:25:10.4 |
HIP 97442 |
4.06 |
| 2026-10-15 12:00 |
19:48:32.74 |
+21:23:32.1 |
HIP 97442 |
3.59 |
| 2026-10-16 00:00 |
19:48:34.36 |
+21:21:54.1 |
HIP 97442 |
3.88 |