Asteroids

2021WM2 help

Last update: 2026-03-17 23:26 UTC

Orbital Properties

Epoch

61200.0

MJD

Orbit type

Apollo

Perihelion (q)

0.831

Aphelion (Q)

2.971

Eccentricity (e)

0.563

Inclination (i)

2.3

deg

Orbit period (P)

957.5

Earth MOID

0.01765

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

61200.0000

1-sigma variation

Unit

MJD

Semimajor Axis

Value

1.901215

1-sigma variation

0.002973

Unit

Eccentricity (e)

Value

0.562713

1-sigma variation

0.000765

Unit

Inclination (i)

Value

2.2957

1-sigma variation

0.0032

Unit

Long. of Ascending Node (Ω)

Value

46.5594

1-sigma variation

0.0022

Unit

Arg. of Perihelion (ω)

Value

82.1900

1-sigma variation

0.0012

Unit

Mean Anomaly (M)

Value

244.44132

1-sigma variation

1.41064

Unit

Perihelion distance

Value

0.831377

1-sigma variation

Unit

Aphelion distance

Value

2.971053

1-sigma variation

Unit

Asc. Node-Earth Sep.

Value

0.216789

1-sigma variation

Unit

Desc. Node-Earth Sep.

Value

0.396593

1-sigma variation

Unit

MOID

Value

0.017652

1-sigma variation

Unit

Orbit Period

Value

957.5140

1-sigma variation

Unit

U parameter

Value

8.1

1-sigma variation

Unit

Covariance Matrix

	a	e	i	Ω	ω	M
a	8.84130E-6	2.27592E-6	9.42727E-6	6.37227E-6	3.41420E-6	-4.19445E-3
e	2.27592E-6	5.85867E-7	2.42677E-6	1.64043E-6	8.78840E-7	-1.07973E-3
i	9.42727E-6	2.42677E-6	1.00542E-5	6.81242E-6	3.62648E-6	-4.47244E-3
Ω	6.37227E-6	1.64043E-6	6.81242E-6	4.74418E-6	2.33758E-6	-3.02311E-3
ω	3.41420E-6	8.78840E-7	3.62648E-6	2.33758E-6	1.42679E-6	-1.61975E-3
M	-4.19445E-3	-1.07973E-3	-4.47244E-3	-3.02311E-3	-1.61975E-3	1.98991E0

Date of computation: 2026-03-17 23:26 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

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

1577

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

Note: Ephemerides requests are limited to a maximum of 1000 points and a final date not exceeding 2040/12/31 00:00.

Close Approaches for 2021WM2 from 1950 to 2126

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	0.1298398
EARTH	1966-11-21 02:20	> 1 d	0.1809727	0.0115429	0.0674302
EARTH	1980-03-21 00:59	> 1 mo	0.0501983	0.0268290	0.2875570
EARTH	2001-01-27 04:31	> 1 mo	0.1569300	0.1211788	0.0122045
MARS	2014-06-19 19:19	> 1 d	0.0436878	0.0036478	0.0916164
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	0.2025966
EARTH	2042-11-27 15:30	> 1 w	0.0980141	0.0174923	0.3136935
EARTH	2056-03-30 01:54	> 1 w	0.0348529	0.0252442	0.1528898
EARTH	2063-11-26 03:41	> 1 w	0.1275763	0.0157237	0.1283482
EARTH	2077-04-05 18:02	> 1 w	0.1027693	0.0244772	0.1172301
MARS	2084-10-10 00:32	> 1 w	0.0150428	0.0001826	0.1868104
EARTH	2084-12-01 09:57	> 1 w	0.0530858	0.0193702	0.2040793
EARTH	2098-04-07 04:12	> 1 w	0.1126936	0.0236795	0.4350613
EARTH	2105-11-28 14:34	> 1 mo	0.1109170	0.0185334	0.6605307
EARTH	2119-04-04 09:25	> 1 mo	0.0615668	0.0240337	0.7200980
EARTH	2126-11-27 08:55	> 1 w	0.1295304	0.0165280	0.2484694

Download as:

Stationary Points

Ecc. an. ast.	Ecc. an. Earth	Distance in au	Classification
328.70057619	332.07766854	0.01767955	MINIMUM
32.70067743	84.49369657	0.02570598	MINIMUM
0.92583025	28.61370369	0.15817342	SADDLE
0.85682945	208.46851316	1.84728135	SADDLE
180.24067693	207.71063243	1.95619318	SADDLE
180.22013577	27.69491954	3.95603720	MAXIMUM

Download:

MOID Plots

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