Asteroids

2021KH2 help

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

Orbital Properties

Epoch

61000.0

MJD

Orbit type

Apollo

Perihelion (q)

1.007

Aphelion (Q)

1.049

Eccentricity (e)

0.020

Inclination (i)

12.3

deg

Orbit period (P)

380.7

Earth MOID

0.00413

U parameter

2.5

Next Earth close approach

Date

2045-05-16

Nominal distance (from Earth center)

0.17618

26355440

Maximum Brightness

24.4

mag

Risk

Object is not in risk list

Physical Properties

Absolute Magnitude (H)

25.3

mag

Diameter

23 - 50*

Taxonomic type

Rotation period (T)

Discovery Information

Discovery Date

2021-05-21

Observatory

ATLAS-MLO, Mauna Loa

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

1.028045

1-sigma variation

1.640E-7

Unit

Eccentricity (e)

Value

0.020286

1-sigma variation

2.315E-7

Unit

Inclination (i)

Value

12.2864

1-sigma variation

0.0001

Unit

Long. of Ascending Node (Ω)

Value

240.8788

1-sigma variation

3.153E-6

Unit

Arg. of Perihelion (ω)

Value

62.5036

1-sigma variation

0.0001

Unit

Mean Anomaly (M)

Value

54.36043

1-sigma variation

0.00029

Unit

Perihelion distance

Value

1.007190

1-sigma variation

Unit

Aphelion distance

Value

1.048900

1-sigma variation

Unit

Asc. Node-Earth Sep.

Value

0.004179

1-sigma variation

Unit

Desc. Node-Earth Sep.

Value

0.049791

1-sigma variation

Unit

MOID

Value

0.004134

1-sigma variation

Unit

Orbit Period

Value

380.7295

1-sigma variation

Unit

U parameter

Value

2.5

1-sigma variation

Unit

Covariance Matrix

	a	e	i	Ω	ω	M
a	2.68963E-14	3.79529E-14	1.38550E-11	1.04972E-13	-1.26479E-11	-4.66686E-11
e	3.79529E-14	5.35869E-14	1.95635E-11	1.51797E-13	-1.78398E-11	-6.58618E-11
i	1.38550E-11	1.95635E-11	7.75146E-9	8.69161E-11	-6.14250E-9	-2.44601E-8
Ω	1.04972E-13	1.51797E-13	8.69161E-11	9.94274E-12	-6.24965E-11	-1.78965E-10
ω	-1.26479E-11	-1.78398E-11	-6.14250E-9	-6.24965E-11	6.48973E-9	2.14109E-8
M	-4.66686E-11	-6.58618E-11	-2.44601E-8	-1.78965E-10	2.14109E-8	8.15150E-8

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

25.27

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

23 - 50*

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

189

Unit

Source

[1]

Unobserved

Value

1423

Unit

Source

[1]

Normalized RMS of residuals

Value

0.57852

Unit

Source

[1]

Astrometry Summary

First Observation
Last Observation
Total Optical Observations (Discarded)

Optical

Value

Unit

Source

First Observation

Value

2021-05-21.30833

Unit

Source

[2]

Last Observation

Value

2021-11-26.331635

Unit

Source

[2]

Total Optical Observations (Discarded)

Value

86 (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 2021KH2 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	1965-05-22 13:55	119.9	0.0056091	0.0047050	0.0012915
EARTH	1965-11-21 00:40	205.6	0.0510728	0.0494305	0.0006775
EARTH	1990-05-22 14:44	3.0	0.0085751	0.0084031	0.0000577
EARTH	1990-11-23 03:38	4.6	0.0397994	0.0397367	0.0000210
EARTH	1991-05-28 23:20	1.3	0.1918338	0.1916454	0.0000628
EARTH	1991-11-16 03:55	1.6	0.1858207	0.1856377	0.0000610
EARTH	2020-05-16 06:08	< 1 min	0.1971936	0.1971866	0.0000023
EARTH	2020-12-05 06:04	< 1 min	0.1971644	0.1971586	0.0000019
EARTH	2021-05-22 12:15	< 1 s	0.0062899	0.0062898	0.0000000
EARTH	2021-11-21 00:24	< 1 min	0.0494206	0.0494197	0.0000003
EARTH	2045-05-16 14:35	1.1	0.1761752	0.1760692	0.0000354
EARTH	2045-12-05 11:09	4.2	0.1628563	0.1627667	0.0000299
EARTH	2046-05-25 06:14	1.6	0.0796433	0.0795370	0.0000354
EARTH	2046-11-16 14:25	2.1	0.0973275	0.0972461	0.0000271
EARTH	2069-12-08 22:14	6.8	0.1859598	0.1858019	0.0000527
EARTH	2070-05-24 09:15	2.7	0.0570864	0.0569033	0.0000610
EARTH	2070-11-17 06:10	4.5	0.0839726	0.0838429	0.0000433
EARTH	2093-05-22 14:34	6.2	0.0148505	0.0144843	0.0001224
EARTH	2093-11-17 23:04	3.4	0.0689940	0.0689347	0.0000201
EARTH	2113-05-17 00:08	93.3	0.1956818	0.1852970	0.0034617
EARTH	2113-12-07 17:21	490.0	0.1587040	0.1504100	0.0028021
EARTH	2114-05-27 02:23	131.2	0.1146785	0.1040753	0.0035349
EARTH	2114-11-12 13:00	228.3	0.1459675	0.1372328	0.0029463

Download as:

Stationary Points

Ecc. an. ast.	Ecc. an. Earth	Distance in au	Classification
298.67111953	138.24922629	0.00593295	MINIMUM
114.58578692	317.51035160	0.04926982	MINIMUM
26.77622068	229.24865432	0.21612648	SADDLE
206.54873867	46.56400798	0.22520656	SADDLE
4.06138225	25.27857532	1.98277263	SADDLE
153.09251968	174.29996207	2.05879766	MAXIMUM

Download:

MOID Plots

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