Asteroids

2021JT help

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

Orbital Properties

Epoch

61000.0

MJD

Orbit type

Apollo

Perihelion (q)

0.916

Aphelion (Q)

1.747

Eccentricity (e)

0.312

Inclination (i)

2.3

deg

Orbit period (P)

561.0

Earth MOID

0.00042

U parameter

7.5

Next Earth close approach

Date

2044-07-21

Nominal distance (from Earth center)

0.10106

15117831

Maximum Brightness

31.5

mag

Risk

Object is not in risk list

Physical Properties

Absolute Magnitude (H)

27.3

mag

Diameter

9 - 21*

Taxonomic type

Rotation period (T)

Discovery Information

Discovery Date

2021-05-03

Observatory

Pan-STARRS 1, Haleakala

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

1.331200

1-sigma variation

0.000525

Unit

Eccentricity (e)

Value

0.312119

1-sigma variation

0.000290

Unit

Inclination (i)

Value

2.2583

1-sigma variation

0.0002

Unit

Long. of Ascending Node (Ω)

Value

50.8447

1-sigma variation

0.1154

Unit

Arg. of Perihelion (ω)

Value

233.6327

1-sigma variation

0.1018

Unit

Mean Anomaly (M)

Value

314.49631

1-sigma variation

0.51238

Unit

Perihelion distance

Value

0.915708

1-sigma variation

Unit

Aphelion distance

Value

1.746693

1-sigma variation

Unit

Asc. Node-Earth Sep.

Value

0.484166

1-sigma variation

Unit

Desc. Node-Earth Sep.

Value

0.002460

1-sigma variation

Unit

MOID

Value

0.000424

1-sigma variation

Unit

Orbit Period

Value

561.0009

1-sigma variation

Unit

U parameter

Value

7.5

1-sigma variation

Unit

Covariance Matrix

	a	e	i	Ω	ω	M
a	2.75995E-7	1.52309E-7	7.44630E-8	6.06422E-5	-5.34566E-5	-2.69181E-4
e	1.52309E-7	8.40609E-8	4.12225E-8	3.34650E-5	-2.94972E-5	-1.48549E-4
i	7.44630E-8	4.12225E-8	2.26529E-8	1.63510E-5	-1.43763E-5	-7.26443E-5
Ω	6.06422E-5	3.34650E-5	1.63510E-5	1.33245E-2	-1.17458E-2	-5.91448E-2
ω	-5.34566E-5	-2.94972E-5	-1.43763E-5	-1.17458E-2	1.03549E-2	5.21362E-2
M	-2.69181E-4	-1.48549E-4	-7.26443E-5	-5.91448E-2	5.21362E-2	2.62534E-1

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

27.311

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

9 - 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

1604

Unit

Source

[1]

Normalized RMS of residuals

Value

0.595771

Unit

Source

[1]

Astrometry Summary

First Observation
Last Observation
Total Optical Observations (Discarded)

Optical

Value

Unit

Source

First Observation

Value

2021-05-01.40612

Unit

Source

[2]

Last Observation

Value

2021-05-07.304988

Unit

Source

[2]

Total Optical Observations (Discarded)

Value

26 (1)

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 2021JT 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	1950-09-01 01:17	> 1 mo	0.0422136	0.0383745	0.3297945
EARTH	1967-06-01 12:32	> 1 mo	0.0730004	0.0075687	0.6760818
MARS	1983-04-20 14:26	> 1 d	0.0071433	0.0028192	0.0915101
EARTH	1984-04-27 15:04	> 1 d	0.1659723	0.0040498	0.1081284
EARTH	1987-08-27 06:25	> 1 w	0.0414743	0.0384216	0.0213056
EARTH	2004-06-17 10:51	> 1 w	0.0946370	0.0537828	0.0141509
EARTH	2021-05-10 11:12	< 1 min	0.0150223	0.0149917	0.0000102
EARTH	2024-09-02 00:55	1349.8	0.0428541	0.0381429	0.0036536
MARS	2043-12-12 09:25	> 1 w	0.0418768	0.0116358	0.0441684
EARTH	2044-07-21 12:26	> 1 mo	0.1010565	0.0664444	0.0152920
MARS	2060-11-22 06:21	> 1 d	0.0449444	0.0116353	0.0342692
EARTH	2064-06-11 15:57	> 1 w	0.0883825	0.0330533	0.0188880
EARTH	2084-06-11 12:32	> 1 w	0.0882363	0.0183037	0.0256668
EARTH	2104-07-23 02:18	> 1 mo	0.1013991	0.0663304	0.0148911
MARS	2111-09-04 06:19	> 1 d	0.0116330	0.0114916	0.0045923
EARTH	2121-05-02 22:49	> 1 w	0.1200374	0.0001390	0.1215153
EARTH	2124-08-29 06:20	> 1 w	0.0415050	0.0376976	0.0523433

Download as:

Stationary Points

Ecc. an. ast.	Ecc. an. Earth	Distance in au	Classification
320.59301144	128.87275552	0.00074676	MINIMUM
39.43029461	235.66696525	0.03827211	MINIMUM
1.08806202	183.77715937	0.10503872	SADDLE
180.10380713	2.26040469	0.76417858	SADDLE
359.95098180	2.17651354	1.89933588	SADDLE
179.89124851	182.10723309	2.76266619	MAXIMUM

Download:

MOID Plots

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