C/2026 A1 (MAPS)
Metadata
| Parameter | Value |
|---|---|
| Designation | C/2026 A1 (MAPS) |
| Type | C |
| Perihelion (tp_cal, UTC) | 2026-04-04T14:23:37.898880Z |
| Orbit solution date (soln_date, UTC) | 2026-06-05T03:03:24Z |
| Obs used | 472 |
| NEO | - |
| M1 | 14.800 |
| K1 | 14.500 |
| PC | - |
| Discovery observation (MPC, UTC) | 2026-01-13T03:38:48.480000Z |
| Discovery magnitude (MPC) | 17.80 G |
| Discovery observatory (MPC) | W94 · MAPS, San Pedro de Atacama |
Osculating Elements
| Parameter | Value |
|---|---|
| Epoch (epoch_cal, TDB) | 2026-02-12.0000000 |
| e | 0.99996265 |
| q (au) | 0.005729 |
| a (au) | 153.392016 |
| i (deg) | 144.493658 |
| Ω (om, deg) | 7.865158 |
| ω (w, deg) | 86.324709 |
| M (ma, deg) | 359.973230 |
Magnitude
Scatter + Global Linear
$$ M_a = (13.441 + 4.858\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
Model Parameters
| Parameter | Value |
|---|---|
| H0 | 13.441 |
| n | 4.858 |
| gf | 1.000 |
| gb | -0.500 |
| 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 |
|---|---|---|---|
| 2026-01-13 | 2026-03-11 | +7.1892 | -2.117 |
| 2026-03-11 | 2026-04-03 | -2.1269 | -2.314 |
| 2026-04-03 | 2026-04-04 | -6.6927 | -6.419 |
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 | 06:12:08.68 | +00:33:33.4 | HIP 29420 | 12.17 |
| 2026-06-01 12:00 | 06:13:03.06 | +00:32:06.1 | HIP 29506 | 13.34 |
| 2026-06-02 00:00 | 06:13:57.01 | +00:30:37.9 | HIP 29506 | 20.70 |
| 2026-06-02 12:00 | 06:14:50.53 | +00:29:08.9 | HIP 29613 | 23.27 |
| 2026-06-03 00:00 | 06:15:43.65 | +00:27:39.0 | HIP 29715 | 22.64 |
| 2026-06-03 12:00 | 06:16:36.35 | +00:26:08.3 | HIP 29933 | 22.89 |
| 2026-06-04 00:00 | 06:17:28.66 | +00:24:36.7 | HIP 29933 | 10.65 |
| 2026-06-04 12:00 | 06:18:20.58 | +00:23:04.2 | HIP 29933 | 7.00 |
| 2026-06-05 00:00 | 06:19:12.12 | +00:21:30.8 | HIP 29933 | 17.98 |
| 2026-06-05 12:00 | 06:20:03.27 | +00:19:56.5 | HIP 30177 | 15.04 |
| 2026-06-06 00:00 | 06:20:54.06 | +00:18:21.4 | HIP 30177 | 4.18 |
| 2026-06-06 12:00 | 06:21:44.48 | +00:16:45.3 | HIP 30257 | 3.12 |
| 2026-06-07 00:00 | 06:22:34.54 | +00:15:08.4 | HIP 30257 | 10.26 |
| 2026-06-07 12:00 | 06:23:24.25 | +00:13:30.5 | HIP 30431 | 16.62 |
| 2026-06-08 00:00 | 06:24:13.62 | +00:11:51.8 | HIP 30431 | 14.12 |
| 2026-06-08 12:00 | 06:25:02.64 | +00:10:12.1 | HIP 30431 | 20.72 |
| 2026-06-09 00:00 | 06:25:51.33 | +00:08:31.5 | HIP 30709 | 19.47 |
| 2026-06-09 12:00 | 06:26:39.69 | +00:06:50.0 | HIP 30709 | 7.48 |
| 2026-06-10 00:00 | 06:27:27.72 | +00:05:07.6 | HIP 30709 | 5.51 |
| 2026-06-10 12:00 | 06:28:15.43 | +00:03:24.3 | HIP 30874 | 10.17 |
| 2026-06-11 00:00 | 06:29:02.83 | +00:01:40.0 | HIP 30874 | 6.56 |
| 2026-06-11 12:00 | 06:29:49.92 | -00:00:05.2 | HIP 30951 | 5.80 |
| 2026-06-12 00:00 | 06:30:36.70 | -00:01:51.3 | HIP 30951 | 13.13 |
| 2026-06-12 12:00 | 06:31:23.18 | -00:03:38.3 | HIP 30951 | 24.23 |
| 2026-06-13 00:00 | 06:32:09.36 | -00:05:26.3 | HIP 31291 | 25.76 |
| 2026-06-13 12:00 | 06:32:55.25 | -00:07:15.3 | HIP 31291 | 14.84 |
| 2026-06-14 00:00 | 06:33:40.85 | -00:09:05.1 | HIP 31291 | 6.80 |
| 2026-06-14 12:00 | 06:34:26.17 | -00:10:56.0 | HIP 31291 | 11.72 |
| 2026-06-15 00:00 | 06:35:11.20 | -00:12:47.7 | HIP 31455 | 4.92 |
| 2026-06-15 12:00 | 06:35:55.95 | -00:14:40.5 | HIP 31455 | 9.79 |
| 2026-06-16 00:00 | 06:36:40.43 | -00:16:34.1 | HIP 31455 | 20.56 |
| 2026-06-16 12:00 | 06:37:24.63 | -00:18:28.7 | HIP 31707 | 23.81 |
| 2026-06-17 00:00 | 06:38:08.57 | -00:20:24.3 | HIP 31707 | 20.75 |
| 2026-06-17 12:00 | 06:38:52.24 | -00:22:20.8 | HIP 31707 | 23.24 |
| 2026-06-18 00:00 | 06:39:35.65 | -00:24:18.2 | HIP 31707 | 29.87 |
| 2026-06-18 12:00 | 06:40:18.80 | -00:26:16.6 | HIP 32058 | 25.34 |
| 2026-06-19 00:00 | 06:41:01.69 | -00:28:16.0 | HIP 32058 | 17.02 |
| 2026-06-19 12:00 | 06:41:44.33 | -00:30:16.3 | HIP 32058 | 13.27 |
| 2026-06-20 00:00 | 06:42:26.71 | -00:32:17.5 | HIP 32058 | 17.24 |
| 2026-06-20 12:00 | 06:43:08.85 | -00:34:19.6 | HIP 32058 | 25.48 |
| 2026-06-21 00:00 | 06:43:50.75 | -00:36:22.7 | HIP 32270 | 20.02 |
| 2026-06-21 12:00 | 06:44:32.40 | -00:38:26.8 | HIP 32270 | 17.68 |
| 2026-06-22 00:00 | 06:45:13.81 | -00:40:31.7 | HIP 32398 | 9.39 |