Asteroids

2021WM2 help

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

Orbital Properties

Epoch

61000.0

MJD

Orbit type

Apollo

Perihelion (q)

0.832

Aphelion (Q)

2.971

Eccentricity (e)

0.563

Inclination (i)

2.3

deg

Orbit period (P)

957.6

Earth MOID

0.01768

U parameter

8.1

Next Earth close approach

Date

2035-04-06

Nominal distance (from Earth center)

0.1222

18281386

Maximum Brightness

mag

Risk

Object is not in risk list

Physical Properties

Absolute Magnitude (H)

25.8

mag

Diameter

18 - 40*

Taxonomic type

Rotation period (T)

Discovery Information

Discovery Date

2021-11-28

Observatory

Mt. Lemmon Survey

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

1.901336

1-sigma variation

0.002970

Unit

Eccentricity (e)

Value

0.562661

1-sigma variation

0.000766

Unit

Inclination (i)

Value

2.2957

1-sigma variation

0.0032

Unit

Long. of Ascending Node (Ω)

Value

46.5696

1-sigma variation

0.0022

Unit

Arg. of Perihelion (ω)

Value

82.1709

1-sigma variation

0.0012

Unit

Mean Anomaly (M)

Value

169.27310

1-sigma variation

1.23428

Unit

Perihelion distance

Value

0.831528

1-sigma variation

Unit

Aphelion distance

Value

2.971144

1-sigma variation

Unit

Asc. Node-Earth Sep.

Value

0.216919

1-sigma variation

Unit

Desc. Node-Earth Sep.

Value

0.395672

1-sigma variation

Unit

MOID

Value

0.017680

1-sigma variation

Unit

Orbit Period

Value

957.6056

1-sigma variation

Unit

U parameter

Value

8.1

1-sigma variation

Unit

Covariance Matrix

	a	e	i	Ω	ω	M
a	8.82311E-6	2.27515E-6	9.42731E-6	6.58236E-6	3.41242E-6	-3.66626E-3
e	2.27515E-6	5.86677E-7	2.43096E-6	1.69743E-6	8.79894E-7	-9.45392E-4
i	9.42731E-6	2.43096E-6	1.00750E-5	7.05094E-6	3.63210E-6	-3.91732E-3
Ω	6.58236E-6	1.69743E-6	7.05094E-6	5.06215E-6	2.42260E-6	-2.73517E-3
ω	3.41242E-6	8.79894E-7	3.63210E-6	2.42260E-6	1.42815E-6	-1.41796E-3
M	-3.66626E-3	-9.45392E-4	-3.91732E-3	-2.73517E-3	-1.41796E-3	1.52344E0

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

25.807

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

18 - 40*

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

Unit

Source

[1]

Unobserved

Value

1379

Unit

Source

[1]

Normalized RMS of residuals

Value

0.410653

Unit

Source

[1]

Astrometry Summary

First Observation
Last Observation
Total Optical Observations (Discarded)

Optical

Value

Unit

Source

First Observation

Value

2021-11-28.153135

Unit

Source

[2]

Last Observation

Value

2021-12-05.70598

Unit

Source

[2]

Total Optical Observations (Discarded)

Value

35 (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 2021WM2 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	1959-04-03 07:28	> 1 w	0.0879620	0.0272692	0.1298411
EARTH	1966-11-21 02:20	> 1 d	0.1809727	0.0115429	0.0674309
EARTH	1980-03-21 00:59	> 1 mo	0.0501983	0.0268290	0.2875599
EARTH	2001-01-27 04:31	> 1 mo	0.1569300	0.1211785	0.0122047
MARS	2014-06-19 19:19	> 1 d	0.0436878	0.0036478	0.0916173
EARTH	2021-12-06 11:53	< 1 min	0.0210622	0.0209814	0.0000269
EARTH	2035-04-06 16:11	> 1 w	0.1222035	0.0252729	0.2025986
EARTH	2042-11-27 15:30	> 1 w	0.0980141	0.0174923	0.3136967
EARTH	2056-03-30 01:54	> 1 w	0.0348529	0.0252442	0.1528913
EARTH	2063-11-26 03:41	> 1 w	0.1275763	0.0157237	0.1283495
EARTH	2077-04-05 18:02	> 1 w	0.1027693	0.0244772	0.1172312
MARS	2084-10-10 00:32	> 1 w	0.0150428	0.0001826	0.1868123
EARTH	2084-12-01 09:57	> 1 w	0.0530858	0.0193702	0.2040813
EARTH	2098-04-07 04:12	> 1 w	0.1126936	0.0236795	0.4350656
EARTH	2105-11-28 14:34	> 1 mo	0.1109170	0.0185334	0.6605372
EARTH	2119-04-04 09:25	> 1 mo	0.0615668	0.0240337	0.7201052

Download as:

Stationary Points

Ecc. an. ast.	Ecc. an. Earth	Distance in au	Classification
328.70155112	331.13806573	0.01769503	MINIMUM
32.58080878	83.42396000	0.02581072	MINIMUM
0.85592078	27.59740069	0.15790657	SADDLE
0.78199789	207.44516711	1.84581054	SADDLE
180.22053162	206.75339086	1.95771547	SADDLE
180.20084577	26.73875772	3.95580879	MAXIMUM

Download:

MOID Plots

Click on the images to zoom-in and zoom-out