Asteroids

2021JX help

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

Orbital Properties

Epoch

61000.0

MJD

Orbit type

Aten

Perihelion (q)

0.485

Aphelion (Q)

1.052

Eccentricity (e)

0.369

Inclination (i)

1.6

deg

Orbit period (P)

245.9

Earth MOID

0.00912

U parameter

6.8

Next Earth close approach

Date

2048-06-17

Nominal distance (from Earth center)

0.18797

28120462

Maximum Brightness

27.3

mag

Risk

Object is not in risk list

Physical Properties

Absolute Magnitude (H)

27.2

mag

Diameter

10 - 21*

Taxonomic type

Rotation period (T)

Discovery Information

Discovery Date

2021-05-03

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

0.768113

1-sigma variation

0.000041

Unit

Eccentricity (e)

Value

0.369019

1-sigma variation

0.000102

Unit

Inclination (i)

Value

1.6231

1-sigma variation

0.0007

Unit

Long. of Ascending Node (Ω)

Value

63.7385

1-sigma variation

0.0036

Unit

Arg. of Perihelion (ω)

Value

358.9322

1-sigma variation

0.0032

Unit

Mean Anomaly (M)

Value

55.89471

1-sigma variation

0.21273

Unit

Perihelion distance

Value

0.484665

1-sigma variation

Unit

Aphelion distance

Value

1.051562

1-sigma variation

Unit

Asc. Node-Earth Sep.

Value

-0.502360

1-sigma variation

Unit

Desc. Node-Earth Sep.

Value

0.037037

1-sigma variation

Unit

MOID

Value

0.009119

1-sigma variation

Unit

Orbit Period

Value

245.8875

1-sigma variation

Unit

U parameter

Value

6.8

1-sigma variation

Unit

Covariance Matrix

	a	e	i	Ω	ω	M
a	1.69901E-9	-4.21481E-9	-3.04505E-8	1.45087E-7	-1.28936E-7	-8.76864E-6
e	-4.21481E-9	1.04560E-8	7.55355E-8	-3.59861E-7	3.19819E-7	2.17527E-5
i	-3.04505E-8	7.55355E-8	5.47804E-7	-2.62494E-6	2.33432E-6	1.57159E-4
Ω	1.45087E-7	-3.59861E-7	-2.62494E-6	1.26891E-5	-1.12948E-5	-7.48832E-4
ω	-1.28936E-7	3.19819E-7	2.33432E-6	-1.12948E-5	1.00584E-5	6.65468E-4
M	-8.76864E-6	2.17527E-5	1.57159E-4	-7.48832E-4	6.65468E-4	4.52552E-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

27.216

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

10 - 21*

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

1630

Unit

Source

[1]

Normalized RMS of residuals

Value

0.845304

Unit

Source

[1]

Astrometry Summary

First Observation
Last Observation
Total Optical Observations (Discarded)

Optical

Value

Unit

Source

First Observation

Value

2021-05-02.36345

Unit

Source

[2]

Last Observation

Value

2021-05-09.31461

Unit

Source

[2]

Total Optical Observations (Discarded)

Value

39 (4)

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 2021JX 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	1951-06-19 05:03	> 1 w	0.0489615	0.0063310	0.2809525
EARTH	1953-06-11 18:22	> 1 mo	0.0112776	0.0069462	0.2163400
EARTH	1955-05-21 14:55	> 1 mo	0.0384406	0.0332104	0.0182915
EARTH	1957-05-01 08:56	> 1 w	0.0116487	0.0116251	0.0040644
EARTH	1959-04-26 01:12	> 1 d	0.0858092	0.0122654	0.1062471
EARTH	1961-04-26 20:18	> 1 d	0.1895904	0.0130619	0.1198691
VENUS	1975-05-13 07:28	> 1 d	0.0240868	0.0224365	0.0114409
EARTH	1984-06-18 07:20	1.2	0.1805422	0.1649335	0.0052032
EARTH	1986-06-19 15:11	179.6	0.0753454	0.0744440	0.0003010
VENUS	1987-12-06 10:38	374.5	0.0246229	0.0198981	0.0028547
EARTH	1988-06-11 20:53	892.9	0.0103215	0.0072091	0.0022588
EARTH	1990-05-17 05:51	> 1 d	0.0370679	0.0319536	0.0017591
EARTH	1992-04-27 11:35	> 1 d	0.0273165	0.0114471	0.0111770
EARTH	1994-04-25 21:28	363.2	0.1442161	0.1056268	0.0128841
VENUS	2002-01-30 13:05	228.9	0.0216016	0.0194912	0.0019025
VENUS	2003-08-29 04:55	210.2	0.0427008	0.0334176	0.0033359
EARTH	2015-06-19 20:55	18.8	0.1356951	0.1315046	0.0013970
EARTH	2017-06-16 07:40	269.2	0.0198490	0.0152382	0.0015840
EARTH	2019-05-27 21:10	457.8	0.0379640	0.0374380	0.0001758
EARTH	2021-05-02 02:22	< 1 s	0.0117687	0.0117567	0.0000040
EARTH	2023-04-25 22:34	17.0	0.0849056	0.0817732	0.0010446
EARTH	2025-04-26 18:32	67.2	0.1913192	0.1850087	0.0021037
VENUS	2030-05-20 00:38	268.5	0.0305929	0.0200707	0.0043049
VENUS	2031-12-16 06:00	283.4	0.0481650	0.0328281	0.0055168
VENUS	2044-07-11 15:33	280.5	0.0247499	0.0182919	0.0036633
EARTH	2048-06-17 22:55	84.0	0.1879737	0.1782187	0.0032518
EARTH	2050-06-19 15:19	41.9	0.0925224	0.0849543	0.0025236
EARTH	2052-06-14 16:54	322.7	0.0129925	0.0101071	0.0010814
VENUS	2053-06-29 05:58	91.8	0.0280514	0.0262104	0.0007455
EARTH	2054-06-03 22:43	231.8	0.0288711	0.0284224	0.0001502
EARTH	2056-05-17 09:13	179.6	0.0358399	0.0357322	0.0000362
EARTH	2058-05-03 13:47	376.9	0.0128810	0.0118605	0.0004266
EARTH	2060-04-26 22:57	313.8	0.0365690	0.0281299	0.0028452
EARTH	2062-04-25 16:27	15.2	0.1008898	0.0890924	0.0039342
EARTH	2064-04-26 04:18	119.1	0.1740797	0.1607514	0.0044430
VENUS	2066-09-05 01:25	278.6	0.0352598	0.0219006	0.0052688
VENUS	2075-08-21 09:08	125.4	0.0370719	0.0311568	0.0020479
VENUS	2083-01-09 00:41	112.8	0.0232589	0.0216115	0.0008973
EARTH	2095-06-18 23:38	305.7	0.1617649	0.1283138	0.0111544
EARTH	2097-06-18 22:15	225.4	0.0780104	0.0452862	0.0109614
EARTH	2099-06-14 21:24	> 1 d	0.0118132	0.0087888	0.0054884
EARTH	2101-06-06 15:57	> 1 d	0.0255675	0.0112918	0.0055127
EARTH	2103-05-23 07:29	> 1 d	0.0378505	0.0368938	0.0003349
EARTH	2105-05-08 03:45	> 1 d	0.0227469	0.0096765	0.0046330
EARTH	2107-04-30 11:17	465.3	0.0178039	0.0157625	0.0012478
EARTH	2109-04-26 09:49	12.3	0.0849676	0.0758153	0.0030701
EARTH	2111-04-27 16:36	274.5	0.1683211	0.1417149	0.0088756

Download as:

Stationary Points

Ecc. an. ast.	Ecc. an. Earth	Distance in au	Classification
208.78697758	159.87354758	0.00938085	MINIMUM
148.18954633	117.72331495	0.01119501	MINIMUM
178.39858343	138.75850523	0.03922341	SADDLE
356.69417010	316.87615037	0.50307593	SADDLE
356.62576709	136.80858802	1.49675283	SADDLE
178.54637936	318.87457812	2.03904541	MAXIMUM

Download:

MOID Plots

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