| Parameter |
Value |
| Designation |
P/2021 N1 (ZTF) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2026-07-28T12:13:30.578880Z |
| Orbit solution date (soln_date, UTC) |
2026-07-28T14:12:18Z |
| Obs used |
248 |
| NEO |
Yes |
| M1 |
19.200 |
| K1 |
4.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2021-07-02T11:08:00.096000Z |
| Discovery magnitude (MPC) |
18.94 r |
| Discovery observatory (MPC) |
I41 · Palomar Mountain–ZTF |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2024-11-02.0000000 |
| e |
0.67594834 |
| q (au) |
0.965617 |
| a (au) |
2.979825 |
| i (deg) |
11.485944 |
| Ω (om, deg) |
301.127605 |
| ω (w, deg) |
21.236267 |
| M (ma, deg) |
238.613359 |
Magnitude
Scatter + Global Linear
$$
M_a = (19.687 + 3.847\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
19.687 |
| n |
3.847 |
| gf |
0.800 |
| gb |
-1.000 |
| k |
0.800 |
| 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
Finding Chart
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
03:10:37.83 |
+31:40:27.2 |
HIP 14840 |
28.38 |
| 2026-07-29 12:00 |
03:12:23.32 |
+32:01:18.4 |
HIP 14784 |
22.87 |
| 2026-07-30 00:00 |
03:14:07.89 |
+32:21:39.1 |
HIP 15102 |
19.82 |
| 2026-07-30 12:00 |
03:15:51.57 |
+32:41:30.4 |
HIP 15191 |
9.94 |
| 2026-07-31 00:00 |
03:17:34.38 |
+33:00:53.0 |
HIP 15191 |
24.42 |
| 2026-07-31 12:00 |
03:19:16.33 |
+33:19:48.0 |
HIP 15447 |
1.27 |
| 2026-08-01 00:00 |
03:20:57.44 |
+33:38:16.0 |
HIP 15495 |
16.37 |
| 2026-08-01 12:00 |
03:22:37.73 |
+33:56:17.9 |
HIP 15877 |
31.21 |
| 2026-08-02 00:00 |
03:24:17.22 |
+34:13:54.4 |
HIP 15877 |
4.17 |
| 2026-08-02 12:00 |
03:25:55.91 |
+34:31:06.4 |
HIP 16075 |
14.69 |
| 2026-08-03 00:00 |
03:27:33.82 |
+34:47:54.6 |
HIP 16107 |
1.04 |
| 2026-08-03 12:00 |
03:29:10.95 |
+35:04:19.5 |
HIP 16175 |
22.71 |
| 2026-08-04 00:00 |
03:30:47.33 |
+35:20:22.0 |
HIP 16518 |
24.11 |
| 2026-08-04 12:00 |
03:32:22.96 |
+35:36:02.7 |
HIP 16517 |
4.91 |
| 2026-08-05 00:00 |
03:33:57.85 |
+35:51:22.1 |
HIP 16640 |
13.87 |
| 2026-08-05 12:00 |
03:35:32.01 |
+36:06:21.0 |
HIP 16640 |
17.13 |
| 2026-08-06 00:00 |
03:37:05.44 |
+36:20:59.8 |
HIP 16987 |
17.60 |
| 2026-08-06 12:00 |
03:38:38.16 |
+36:35:19.2 |
HIP 16987 |
20.15 |
| 2026-08-07 00:00 |
03:40:10.16 |
+36:49:19.6 |
HIP 17224 |
30.28 |
| 2026-08-07 12:00 |
03:41:41.45 |
+37:03:01.8 |
HIP 17308 |
14.94 |
| 2026-08-08 00:00 |
03:43:12.03 |
+37:16:26.0 |
HIP 17308 |
10.71 |
| 2026-08-08 12:00 |
03:44:41.92 |
+37:29:32.9 |
HIP 17536 |
8.62 |
| 2026-08-09 00:00 |
03:46:11.11 |
+37:42:22.8 |
HIP 17536 |
21.03 |
| 2026-08-09 12:00 |
03:47:39.60 |
+37:54:56.4 |
HIP 17741 |
7.04 |
| 2026-08-10 00:00 |
03:49:07.40 |
+38:07:13.9 |
HIP 17930 |
18.46 |
| 2026-08-10 12:00 |
03:50:34.51 |
+38:19:15.9 |
HIP 17930 |
27.51 |
| 2026-08-11 00:00 |
03:52:00.92 |
+38:31:02.7 |
HIP 18238 |
24.15 |
| 2026-08-11 12:00 |
03:53:26.65 |
+38:42:34.8 |
HIP 18238 |
12.15 |
| 2026-08-12 00:00 |
03:54:51.69 |
+38:53:52.5 |
HIP 18238 |
22.97 |
| 2026-08-12 12:00 |
03:56:16.05 |
+39:04:56.3 |
HIP 18565 |
29.67 |
| 2026-08-13 00:00 |
03:57:39.71 |
+39:15:46.4 |
HIP 18552 |
13.30 |
| 2026-08-13 12:00 |
03:59:02.69 |
+39:26:23.3 |
HIP 18552 |
9.51 |
| 2026-08-14 00:00 |
04:00:24.99 |
+39:36:47.3 |
HIP 18688 |
24.20 |
| 2026-08-14 12:00 |
04:01:46.60 |
+39:46:58.7 |
HIP 18770 |
19.57 |
| 2026-08-15 00:00 |
04:03:07.52 |
+39:56:57.8 |
HIP 18973 |
15.57 |
| 2026-08-15 12:00 |
04:04:27.76 |
+40:06:45.0 |
HIP 19083 |
16.26 |
| 2026-08-16 00:00 |
04:05:47.31 |
+40:16:20.6 |
HIP 19083 |
3.95 |
| 2026-08-16 12:00 |
04:07:06.18 |
+40:25:44.8 |
HIP 19083 |
20.08 |
| 2026-08-17 00:00 |
04:08:24.35 |
+40:34:58.0 |
HIP 19389 |
26.75 |
| 2026-08-17 12:00 |
04:09:41.84 |
+40:44:00.5 |
HIP 19521 |
21.03 |
| 2026-08-18 00:00 |
04:10:58.64 |
+40:52:52.5 |
HIP 19563 |
5.68 |
| 2026-08-18 12:00 |
04:12:14.75 |
+41:01:34.2 |
HIP 19563 |
11.29 |
| 2026-08-19 00:00 |
04:13:30.17 |
+41:10:06.0 |
HIP 19563 |
27.82 |