P/2021 R6 (Groeller)

Metadata

Parameter Value
Designation P/2021 R6 (Groeller)
Type P
Perihelion (tp_cal, UTC) 2021-10-31T20:32:49.485120Z
Orbit solution date (soln_date, UTC) 2021-11-20T19:13:09Z
Obs used 105
NEO -
M1 14.900
K1 10.000
PC -
Discovery observation (MPC, UTC) 2021-09-12T11:00:52.588800Z
Discovery magnitude (MPC) 20.27 G
Discovery observatory (MPC) G96 · University of Arizona Mt. Lemmon Survey
Osculating Elements
Parameter Value
Epoch (epoch_cal, TDB) 2021-09-29.0000000
e 0.59323774
q (au) 2.552105
a (au) 6.274194
i (deg) 34.926106
Ω (om, deg) 176.113969
ω (w, deg) 220.719673
M (ma, deg) 357.939448

Magnitude

P/2021 R6 (Groeller) · Magnitude (Full range)

Scatter + Global Linear

$$ M_a = (15.810 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

Model Parameters

Parameter Value
H0 15.810
n 6.000
gf 1.000
gb -0.826
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

Ephemeris

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-07-29 00:00 12:27:45.50 +06:26:33.0 HIP 60800 17.35
2026-07-29 12:00 12:27:54.02 +06:25:38.9 HIP 60800 16.77
2026-07-30 00:00 12:28:02.62 +06:24:44.4 HIP 60800 16.50
2026-07-30 12:00 12:28:11.28 +06:23:49.6 HIP 60800 16.56
2026-07-31 00:00 12:28:20.02 +06:22:54.5 HIP 60800 16.95
2026-07-31 12:00 12:28:28.82 +06:21:59.0 HIP 60800 17.65
2026-08-01 00:00 12:28:37.70 +06:21:03.3 HIP 60800 18.65
2026-08-01 12:00 12:28:46.64 +06:20:07.2 HIP 60800 19.89
2026-08-02 00:00 12:28:55.64 +06:19:10.8 HIP 60800 21.35
2026-08-02 12:00 12:29:04.72 +06:18:14.1 HIP 60915 20.60
2026-08-03 00:00 12:29:13.86 +06:17:17.1 HIP 60915 19.80
2026-08-03 12:00 12:29:23.07 +06:16:19.8 HIP 60915 19.29
2026-08-04 00:00 12:29:32.35 +06:15:22.2 HIP 60915 19.09
2026-08-04 12:00 12:29:41.69 +06:14:24.4 HIP 60915 19.22
2026-08-05 00:00 12:29:51.09 +06:13:26.2 HIP 60915 19.68
2026-08-05 12:00 12:30:00.56 +06:12:27.7 HIP 61004 20.02
2026-08-06 00:00 12:30:10.10 +06:11:29.0 HIP 61004 18.86
2026-08-06 12:00 12:30:19.70 +06:10:30.0 HIP 61004 18.00
2026-08-07 00:00 12:30:29.36 +06:09:30.7 HIP 61004 17.48
2026-08-07 12:00 12:30:39.09 +06:08:31.2 HIP 61004 17.34
2026-08-08 00:00 12:30:48.87 +06:07:31.4 HIP 61004 17.59
2026-08-08 12:00 12:30:58.72 +06:06:31.3 HIP 61004 18.24
2026-08-09 00:00 12:31:08.64 +06:05:31.0 HIP 61004 19.23
2026-08-09 12:00 12:31:18.61 +06:04:30.5 HIP 61004 20.54
2026-08-10 00:00 12:31:28.64 +06:03:29.6 HIP 61149 21.63
2026-08-10 12:00 12:31:38.74 +06:02:28.6 HIP 61149 20.12
2026-08-11 00:00 12:31:48.89 +06:01:27.3 HIP 61149 18.87
2026-08-11 12:00 12:31:59.11 +06:00:25.8 HIP 61149 17.95
2026-08-12 00:00 12:32:09.38 +05:59:24.0 HIP 61149 17.41
2026-08-12 12:00 12:32:19.71 +05:58:22.1 HIP 61149 17.30
2026-08-13 00:00 12:32:30.10 +05:57:19.9 HIP 61261 15.58
2026-08-13 12:00 12:32:40.54 +05:56:17.5 HIP 61261 12.99
2026-08-14 00:00 12:32:51.04 +05:55:14.9 HIP 61261 10.50
2026-08-14 12:00 12:33:01.60 +05:54:12.1 HIP 61261 8.20
2026-08-15 00:00 12:33:12.22 +05:53:09.1 HIP 61261 6.35
2026-08-15 12:00 12:33:22.88 +05:52:05.9 HIP 61261 5.44
2026-08-16 00:00 12:33:33.61 +05:51:02.5 HIP 61261 5.93
2026-08-16 12:00 12:33:44.39 +05:49:58.9 HIP 61261 7.57
2026-08-17 00:00 12:33:55.22 +05:48:55.1 HIP 61261 9.82
2026-08-17 12:00 12:34:06.10 +05:47:51.2 HIP 61369 12.07
2026-08-18 00:00 12:34:17.03 +05:46:47.1 HIP 61369 11.83
2026-08-18 12:00 12:34:28.02 +05:45:42.9 HIP 61369 12.29
2026-08-19 00:00 12:34:39.06 +05:44:38.4 HIP 61369 13.40