C/2026 B2 (Sun-Gao)
Metadata
| Parameter | Value |
|---|---|
| Designation | C/2026 B2 (Sun-Gao) |
| Type | C |
| Perihelion (tp_cal, UTC) | 2026-01-10T02:50:33.423360Z |
| Orbit solution date (soln_date, UTC) | 2026-04-21T11:12:17Z |
| Obs used | 185 |
| NEO | - |
| M1 | 13.200 |
| K1 | 10.750 |
| PC | - |
| Discovery observation (MPC, UTC) | 2026-01-19T00:03:36.864000Z |
| Discovery magnitude (MPC) | 15.50 G |
| Discovery observatory (MPC) | N86 · Xingming Observatory-KATS, Nanshan |
Osculating Elements
| Parameter | Value |
|---|---|
| Epoch (epoch_cal, TDB) | 2026-02-11.0000000 |
| e | 0.99754914 |
| q (au) | 1.284251 |
| a (au) | 523.999832 |
| i (deg) | 59.578829 |
| Ω (om, deg) | 234.638503 |
| ω (w, deg) | 47.299179 |
| M (ma, deg) | 0.002620 |
Magnitude
Scatter + Global Linear
$$ M_a = (12.111 + 4.680\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
Model Parameters
| Parameter | Value |
|---|---|
| H0 | 12.111 |
| n | 4.680 |
| gf | 1.000 |
| gb | -0.998 |
| k | 1.000 |
| 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 |
|---|---|---|---|
| 2026-01-19 | 2026-02-25 | -61.2671 | +7.262 |
| 2026-02-25 | 2026-04-09 | +22.7708 | -5.666 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Finding Chart
Ephemeris
| Date/Time (UTC) | RA (J2000) | Dec (J2000) | Nearest HIP | Dist from HIP (arcmin) |
|---|---|---|---|---|
| 2026-06-01 00:00 | 01:47:33.60 | +42:52:23.6 | HIP 8332 | 12.49 |
| 2026-06-01 12:00 | 01:48:29.96 | +42:54:47.2 | HIP 8332 | 15.25 |
| 2026-06-02 00:00 | 01:49:26.03 | +42:57:09.6 | HIP 8378 | 22.32 |
| 2026-06-02 12:00 | 01:50:21.81 | +42:59:31.0 | HIP 8378 | 29.33 |
| 2026-06-03 00:00 | 01:51:17.29 | +43:01:51.2 | HIP 8637 | 26.76 |
| 2026-06-03 12:00 | 01:52:12.48 | +43:04:10.3 | HIP 8637 | 26.01 |
| 2026-06-04 00:00 | 01:53:07.38 | +43:06:28.3 | HIP 8637 | 29.12 |
| 2026-06-04 12:00 | 01:54:01.99 | +43:08:45.3 | HIP 9011 | 22.26 |
| 2026-06-05 00:00 | 01:54:56.30 | +43:11:01.2 | HIP 9011 | 13.87 |
| 2026-06-05 12:00 | 01:55:50.32 | +43:13:16.0 | HIP 9011 | 9.79 |
| 2026-06-06 00:00 | 01:56:44.04 | +43:15:29.8 | HIP 9011 | 14.24 |
| 2026-06-06 12:00 | 01:57:37.48 | +43:17:42.6 | HIP 9194 | 21.25 |
| 2026-06-07 00:00 | 01:58:30.62 | +43:19:54.3 | HIP 9194 | 17.48 |
| 2026-06-07 12:00 | 01:59:23.46 | +43:22:05.1 | HIP 9194 | 18.82 |
| 2026-06-08 00:00 | 02:00:16.02 | +43:24:14.8 | HIP 9450 | 20.12 |
| 2026-06-08 12:00 | 02:01:08.27 | +43:26:23.6 | HIP 9450 | 13.31 |
| 2026-06-09 00:00 | 02:02:00.24 | +43:28:31.4 | HIP 9525 | 6.07 |
| 2026-06-09 12:00 | 02:02:51.91 | +43:30:38.2 | HIP 9525 | 3.88 |
| 2026-06-10 00:00 | 02:03:43.29 | +43:32:44.1 | HIP 9525 | 13.27 |
| 2026-06-10 12:00 | 02:04:34.37 | +43:34:49.0 | HIP 9525 | 22.73 |
| 2026-06-11 00:00 | 02:05:25.15 | +43:36:53.0 | HIP 9893 | 20.66 |
| 2026-06-11 12:00 | 02:06:15.64 | +43:38:56.1 | HIP 9893 | 11.47 |
| 2026-06-12 00:00 | 02:07:05.83 | +43:40:58.2 | HIP 9893 | 3.42 |
| 2026-06-12 12:00 | 02:07:55.73 | +43:42:59.5 | HIP 9893 | 8.01 |
| 2026-06-13 00:00 | 02:08:45.33 | +43:44:59.8 | HIP 9893 | 16.90 |
| 2026-06-13 12:00 | 02:09:34.63 | +43:46:59.2 | HIP 10025 | 20.60 |
| 2026-06-14 00:00 | 02:10:23.63 | +43:48:57.8 | HIP 10196 | 16.43 |
| 2026-06-14 12:00 | 02:11:12.33 | +43:50:55.5 | HIP 10196 | 16.32 |
| 2026-06-15 00:00 | 02:12:00.73 | +43:52:52.3 | HIP 10196 | 20.58 |
| 2026-06-15 12:00 | 02:12:48.83 | +43:54:48.2 | HIP 10340 | 19.60 |
| 2026-06-16 00:00 | 02:13:36.63 | +43:56:43.2 | HIP 10340 | 17.68 |
| 2026-06-16 12:00 | 02:14:24.13 | +43:58:37.4 | HIP 10340 | 19.87 |
| 2026-06-17 00:00 | 02:15:11.33 | +44:00:30.8 | HIP 10626 | 22.31 |
| 2026-06-17 12:00 | 02:15:58.22 | +44:02:23.3 | HIP 10626 | 18.26 |
| 2026-06-18 00:00 | 02:16:44.81 | +44:04:14.9 | HIP 10687 | 16.49 |
| 2026-06-18 12:00 | 02:17:31.10 | +44:06:05.8 | HIP 10687 | 12.21 |
| 2026-06-19 00:00 | 02:18:17.08 | +44:07:55.7 | HIP 10687 | 13.04 |
| 2026-06-19 12:00 | 02:19:02.76 | +44:09:44.9 | HIP 10687 | 18.22 |
| 2026-06-20 00:00 | 02:19:48.14 | +44:11:33.3 | HIP 11031 | 24.95 |
| 2026-06-20 12:00 | 02:20:33.21 | +44:13:20.8 | HIP 11031 | 16.68 |
| 2026-06-21 00:00 | 02:21:17.97 | +44:15:07.5 | HIP 11031 | 8.47 |
| 2026-06-21 12:00 | 02:22:02.43 | +44:16:53.5 | HIP 11031 | 0.56 |
| 2026-06-22 00:00 | 02:22:46.58 | +44:18:38.6 | HIP 11142 | 7.74 |