| 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) |
| 2026-06-01 00:00 |
20:18:49.08 |
+24:18:52.4 |
HIP 100200 |
8.79 |
| 2026-06-01 12:00 |
20:18:43.53 |
+24:20:11.6 |
HIP 100200 |
9.70 |
| 2026-06-02 00:00 |
20:18:37.91 |
+24:21:30.0 |
HIP 100080 |
10.19 |
| 2026-06-02 12:00 |
20:18:32.19 |
+24:22:47.6 |
HIP 100080 |
8.41 |
| 2026-06-03 00:00 |
20:18:26.40 |
+24:24:04.4 |
HIP 100080 |
6.66 |
| 2026-06-03 12:00 |
20:18:20.52 |
+24:25:20.5 |
HIP 100080 |
4.98 |
| 2026-06-04 00:00 |
20:18:14.57 |
+24:26:35.7 |
HIP 100080 |
3.49 |
| 2026-06-04 12:00 |
20:18:08.53 |
+24:27:50.2 |
HIP 100080 |
2.55 |
| 2026-06-05 00:00 |
20:18:02.41 |
+24:29:03.8 |
HIP 100080 |
2.79 |
| 2026-06-05 12:00 |
20:17:56.21 |
+24:30:16.6 |
HIP 100080 |
4.01 |
| 2026-06-06 00:00 |
20:17:49.92 |
+24:31:28.6 |
HIP 100080 |
5.61 |
| 2026-06-06 12:00 |
20:17:43.57 |
+24:32:39.8 |
HIP 100080 |
7.35 |
| 2026-06-07 00:00 |
20:17:37.13 |
+24:33:50.1 |
HIP 100080 |
9.15 |
| 2026-06-07 12:00 |
20:17:30.61 |
+24:34:59.6 |
HIP 100080 |
10.99 |
| 2026-06-08 00:00 |
20:17:24.02 |
+24:36:08.3 |
HIP 99951 |
9.36 |
| 2026-06-08 12:00 |
20:17:17.35 |
+24:37:16.0 |
HIP 99951 |
7.50 |
| 2026-06-09 00:00 |
20:17:10.60 |
+24:38:23.0 |
HIP 99951 |
5.67 |
| 2026-06-09 12:00 |
20:17:03.78 |
+24:39:29.0 |
HIP 99951 |
3.87 |
| 2026-06-10 00:00 |
20:16:56.88 |
+24:40:34.2 |
HIP 99951 |
2.25 |
| 2026-06-10 12:00 |
20:16:49.91 |
+24:41:38.5 |
HIP 99951 |
1.52 |
| 2026-06-11 00:00 |
20:16:42.86 |
+24:42:41.9 |
HIP 99951 |
2.61 |
| 2026-06-11 12:00 |
20:16:35.74 |
+24:43:44.5 |
HIP 99951 |
4.32 |
| 2026-06-12 00:00 |
20:16:28.55 |
+24:44:46.1 |
HIP 99951 |
6.16 |
| 2026-06-12 12:00 |
20:16:21.28 |
+24:45:46.8 |
HIP 99951 |
8.04 |
| 2026-06-13 00:00 |
20:16:13.95 |
+24:46:46.6 |
HIP 99951 |
9.95 |
| 2026-06-13 12:00 |
20:16:06.54 |
+24:47:45.5 |
HIP 99951 |
11.87 |
| 2026-06-14 00:00 |
20:15:59.07 |
+24:48:43.4 |
HIP 99951 |
13.80 |
| 2026-06-14 12:00 |
20:15:51.52 |
+24:49:40.4 |
HIP 99951 |
15.73 |
| 2026-06-15 00:00 |
20:15:43.91 |
+24:50:36.5 |
HIP 99767 |
16.65 |
| 2026-06-15 12:00 |
20:15:36.23 |
+24:51:31.7 |
HIP 99767 |
14.93 |
| 2026-06-16 00:00 |
20:15:28.48 |
+24:52:25.8 |
HIP 99767 |
13.26 |
| 2026-06-16 12:00 |
20:15:20.67 |
+24:53:19.1 |
HIP 99767 |
11.68 |
| 2026-06-17 00:00 |
20:15:12.79 |
+24:54:11.3 |
HIP 99767 |
10.21 |
| 2026-06-17 12:00 |
20:15:04.85 |
+24:55:02.7 |
HIP 99767 |
8.92 |
| 2026-06-18 00:00 |
20:14:56.85 |
+24:55:53.0 |
HIP 99767 |
7.92 |
| 2026-06-18 12:00 |
20:14:48.78 |
+24:56:42.4 |
HIP 99767 |
7.31 |
| 2026-06-19 00:00 |
20:14:40.65 |
+24:57:30.7 |
HIP 99767 |
7.20 |
| 2026-06-19 12:00 |
20:14:32.46 |
+24:58:18.2 |
HIP 99767 |
7.63 |
| 2026-06-20 00:00 |
20:14:24.22 |
+24:59:04.6 |
HIP 99767 |
8.51 |
| 2026-06-20 12:00 |
20:14:15.91 |
+24:59:50.0 |
HIP 99767 |
9.73 |
| 2026-06-21 00:00 |
20:14:07.55 |
+25:00:34.4 |
HIP 99767 |
11.17 |
| 2026-06-21 12:00 |
20:13:59.12 |
+25:01:17.9 |
HIP 99767 |
12.78 |
| 2026-06-22 00:00 |
20:13:50.65 |
+25:02:00.3 |
HIP 99767 |
14.48 |