Asteroids

2021WG help

Last update: 2025-09-10 00:30 UTC

Orbital Properties

Epoch

61000.0

MJD

Orbit type

Aten

Perihelion (q)

0.507

Aphelion (Q)

1.000

Eccentricity (e)

0.327

Inclination (i)

3.3

deg

Orbit period (P)

238.8

Earth MOID

0.00365

U parameter

6.6

Next Earth close approach

Date

2036-10-24

Nominal distance (from Earth center)

0.1114

16665512

Maximum Brightness

28.1

mag

Risk

Object is not in risk list

Physical Properties

Absolute Magnitude (H)

28.8

mag

Diameter

5 - 10*

Taxonomic type

Rotation period (T)

Discovery Information

Discovery Date

2021-11-23

Observatory

GINOP-KHK, Piszkesteto

ORBIT VISUALISATION TOOLS

External links

Proper elements

Epoch

Near present day

Near middle of observation arc

Orbit properties

Epoch
Semimajor Axis
Eccentricity (e)
Inclination (i)
Long. of Ascending Node (Ω)
Arg. of Perihelion (ω)
Mean Anomaly (M)
Perihelion distance
Aphelion distance
Asc. Node-Earth Sep.
Desc. Node-Earth Sep.
MOID
Orbit Period
U parameter

Value

1-sigma variation

Unit

Epoch

Value

61000.0000

1-sigma variation

Unit

MJD

Semimajor Axis

Value

0.753248

1-sigma variation

0.000033

Unit

Eccentricity (e)

Value

0.327105

1-sigma variation

0.000063

Unit

Inclination (i)

Value

3.3094

1-sigma variation

0.0009

Unit

Long. of Ascending Node (Ω)

Value

241.3113

1-sigma variation

0.0001

Unit

Arg. of Perihelion (ω)

Value

350.9948

1-sigma variation

0.0008

Unit

Mean Anomaly (M)

Value

235.07328

1-sigma variation

0.14874

Unit

Perihelion distance

Value

0.506857

1-sigma variation

Unit

Aphelion distance

Value

0.999639

1-sigma variation

Unit

Asc. Node-Earth Sep.

Value

-0.505578

1-sigma variation

Unit

Desc. Node-Earth Sep.

Value

0.006155

1-sigma variation

Unit

MOID

Value

0.003655

1-sigma variation

Unit

Orbit Period

Value

238.7840

1-sigma variation

Unit

U parameter

Value

6.6

1-sigma variation

Unit

Covariance Matrix

	a	e	i	Ω	ω	M
a	1.05849E-9	-2.06112E-9	-2.86940E-8	1.63341E-9	-1.96660E-8	-4.83904E-6
e	-2.06112E-9	4.01461E-9	5.58843E-8	-3.18397E-9	3.77532E-8	9.42376E-6
i	-2.86940E-8	5.58843E-8	7.79793E-7	-4.40622E-8	5.27947E-7	1.31188E-4
Ω	1.63341E-9	-3.18397E-9	-4.40622E-8	2.56998E-9	-2.87900E-8	-7.47051E-6
ω	-1.96660E-8	3.77532E-8	5.27947E-7	-2.87900E-8	6.22599E-7	8.94002E-5
M	-4.83904E-6	9.42376E-6	1.31188E-4	-7.47051E-6	8.94002E-5	2.21233E-2

Date of computation: 2025-09-10 00:30 UTC

Note: The ASCII file is in a format suitable for Orbfit input.

Download ASCII file:

Physical properties

Rotation Period
Quality
Amplitude
Rotation Direction
Spinvector L
Spinvector B

Rotational properties

Value

Unit

Source

Rotation Period

Value

Unit

Source

[-]

Quality

Value

Unit

Source

[-]

Amplitude

Value

Unit

mag

Source

[-]

Rotation Direction

Value

Unit

Source

[-]

Spinvector L

Value

Unit

Source

[-]

Spinvector B

Value

Unit

Source

[-]

Taxonomy
Taxonomy (all)

Taxonomy

Value

Unit

Source

Taxonomy

Value

Unit

Source

[-]

Taxonomy (all)

Value

Unit

Source

[-]

Absolute Magnitude (H)
Slope Parameter (G)

H / G

Value

Unit

Source

Absolute Magnitude (H)

Value

28.791

Unit

mag

Source

[1]

Slope Parameter (G)

Value

0.15**

Unit

mag

Source

[1]

Albedo
Diameter

Size and albedo

Value

Unit

Source

Albedo

Value

0.05 - 0.25

Unit

Source

[2]

Diameter

Value

5 - 10*

Unit

Source

[2]

Color Index Information

Color Index Information

Value

Unit

Source

Color Index Information

Value

Unit

mag

Source

[-]

Sightings

Sightings

Value

Unit

Source

Sightings

Value

Unit

Source

[-]

Download this part as:

Sources

No.	Name	Additional
[1]	ESA Aegis	ESA orbit determination and impact monitoring system
[2]	Estimation	Estimated from absolute magnitude

Observational Information

Arc Length
Unobserved
Normalized RMS of residuals

Arc Information

Value

Unit

Source

Arc Length

Value

0.9

Unit

Source

[1]

Unobserved

Value

1422

Unit

Source

[1]

Normalized RMS of residuals

Value

0.633571

Unit

Source

[1]

Astrometry Summary

First Observation
Last Observation
Total Optical Observations (Discarded)

Optical

Value

Unit

Source

First Observation

Value

2021-11-23.95853

Unit

Source

[2]

Last Observation

Value

2021-11-24.8315

Unit

Source

[2]

Total Optical Observations (Discarded)

Value

57 (0)

Unit

Source

[1]

Radar Summary

First Observation
Last Observation
Delay (Discarded)
Doppler (Discarded)
Total Optical Observations (Discarded)

Radar

Value

Unit

Source

First Observation

Value

Unit

Source

[-]

Last Observation

Value

Unit

Source

[-]

Delay (Discarded)

Value

0 (0)

Unit

Source

[-]

Doppler (Discarded)

Value

0 (0)

Unit

Source

[-]

Total Radar Observations (Discarded)

Value

0 (0)

Unit

Source

[-]

Note: The ASCII file is in a format suitable for Orbfit input.

Sources

No.	Name	Additional
[1]	ESA Aegis	ESA orbit determination and impact monitoring system
[2]	MPC	Minor Planet Center: https://www.minorplanetcenter.net

Computation parameters

As seen from:

Initial Date: *

Final Date: *

Output option:

One line per time step

Time step:*

* - these fields are required

Close Approaches for 2021WG from 1950 to 2125

Body	Date in UTC	Time uncert. in min	Nominal distance in au	Min. possible distance in au	Distance uncert. in au
EARTH	1952-10-26 02:39	1130.2	0.0985466	0.0231473	0.0333968
EARTH	1954-12-09 11:30	> 1 d	0.0700111	0.0070697	0.0332074
EARTH	1965-11-08 10:29	> 1 d	0.0167444	0.0151339	0.0020266
EARTH	1967-12-09 20:13	208.2	0.1861174	0.1601858	0.0086469
MERCURY	1978-07-21 00:06	255.5	0.0432110	0.0431555	0.0000678
EARTH	1978-11-23 16:31	612.4	0.0070616	0.0055816	0.0005095
EARTH	1991-10-29 10:42	635.0	0.0464225	0.0375093	0.0030577
EARTH	1993-12-09 11:16	190.1	0.0879478	0.0747017	0.0044187
MERCURY	1996-02-17 21:49	756.0	0.0477873	0.0434404	0.0021097
EARTH	2004-10-26 01:55	66.2	0.1975180	0.1814719	0.0053532
EARTH	2006-11-15 23:27	> 1 d	0.0129696	0.0113721	0.0007881
EARTH	2008-12-08 17:28	114.1	0.1776754	0.1622422	0.0051460
EARTH	2019-10-25 22:54	9.7	0.1546716	0.1525617	0.0007034
EARTH	2021-11-24 08:24	< 1 min	0.0058445	0.0058408	0.0000012
EARTH	2023-12-08 21:11	20.2	0.1792400	0.1769505	0.0007632
EARTH	2036-10-24 06:59	73.7	0.1114021	0.0971386	0.0047745
EARTH	2038-11-26 18:50	> 1 d	0.0038159	0.0037693	0.0003831
EARTH	2040-12-07 19:57	723.0	0.1757529	0.0308938	0.0494232
EARTH	2053-10-24 02:17	> 1 d	0.1872433	0.0233353	0.3229878
EARTH	2055-11-03 19:39	> 1 mo	0.0174670	0.0154574	0.0950663
EARTH	2057-12-08 02:13	> 1 w	0.0763845	0.0099243	0.5637755
EARTH	2072-10-23 09:30	> 1 d	0.1357951	0.0241180	1.3335561
EARTH	2074-11-14 17:19	> 1 mo	0.0130898	0.0123797	0.1160813
EARTH	2076-12-08 05:33	> 1 w	0.1204770	0.0158288	1.2860853
EARTH	2091-10-24 00:24	> 1 w	0.1140502	0.0231975	0.3958897
EARTH	2093-11-18 22:54	> 1 mo	0.0108357	0.0084630	0.1314023
EARTH	2095-12-08 16:53	> 1 d	0.1270223	0.0114028	0.6327889
EARTH	2110-10-25 01:17	> 1 d	0.1931591	0.0082865	0.0818582
EARTH	2112-10-29 18:55	> 1 d	0.0296018	0.0090031	0.0180510
EARTH	2114-12-05 17:16	> 1 d	0.0323570	0.0154630	0.0557595

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Stationary Points

Ecc. an. ast.	Ecc. an. Earth	Distance in au	Classification
197.00105394	322.78860227	0.00362216	MINIMUM
3.79729435	134.07582547	0.50399114	SADDLE
3.75964145	314.05266107	1.49582695	SADDLE
182.05775783	132.25753193	2.01029791	MAXIMUM

Download:

MOID Plots

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