Asteroids

2021GJ1 help

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

Orbital Properties

Epoch

61000.0

MJD

Orbit type

Amor

Perihelion (q)

1.149

Aphelion (Q)

1.843

Eccentricity (e)

0.232

Inclination (i)

46.8

deg

Orbit period (P)

668.6

Earth MOID

0.14890

U parameter

8.9

Next Earth close approach

Date

2032-03-29

Nominal distance (from Earth center)

0.17371

25987282

Maximum Brightness

mag

Risk

Object is not in risk list

Physical Properties

Absolute Magnitude (H)

22.3

mag

Diameter

90 - 210*

Taxonomic type

Rotation period (T)

Discovery Information

Discovery Date

2021-04-03

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

1.496407

1-sigma variation

0.005484

Unit

Eccentricity (e)

Value

0.231939

1-sigma variation

0.002557

Unit

Inclination (i)

Value

46.7614

1-sigma variation

0.1039

Unit

Long. of Ascending Node (Ω)

Value

191.0862

1-sigma variation

0.0017

Unit

Arg. of Perihelion (ω)

Value

358.4402

1-sigma variation

0.0147

Unit

Mean Anomaly (M)

Value

193.24639

1-sigma variation

5.02873

Unit

Perihelion distance

Value

1.149332

1-sigma variation

Unit

Aphelion distance

Value

1.843482

1-sigma variation

Unit

Asc. Node-Earth Sep.

Value

0.148926

1-sigma variation

Unit

Desc. Node-Earth Sep.

Value

0.842654

1-sigma variation

Unit

MOID

Value

0.148898

1-sigma variation

Unit

Orbit Period

Value

668.6101

1-sigma variation

Unit

U parameter

Value

8.9

1-sigma variation

Unit

Covariance Matrix

	a	e	i	Ω	ω	M
a	3.00751E-5	1.40229E-5	5.69925E-4	-9.06210E-6	8.00299E-5	-2.75779E-2
e	1.40229E-5	6.53836E-6	2.65735E-4	-4.22531E-6	3.73141E-5	-1.28586E-2
i	5.69925E-4	2.65735E-4	1.08001E-2	-1.71726E-4	1.51643E-3	-5.22604E-1
Ω	-9.06210E-6	-4.22531E-6	-1.71726E-4	2.73084E-6	-2.41367E-5	8.30967E-3
ω	8.00299E-5	3.73141E-5	1.51643E-3	-2.41367E-5	2.15026E-4	-7.33862E-2
M	-2.75779E-2	-1.28586E-2	-5.22604E-1	8.30967E-3	-7.33862E-2	2.52881E1

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

22.29

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

90 - 210*

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

1651

Unit

Source

[1]

Normalized RMS of residuals

Value

0.682035

Unit

Source

[1]

Astrometry Summary

First Observation
Last Observation
Total Optical Observations (Discarded)

Optical

Value

Unit

Source

First Observation

Value

2021-04-03.274805

Unit

Source

[2]

Last Observation

Value

2021-04-14.451101

Unit

Source

[2]

Total Optical Observations (Discarded)

Value

110 (2)

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 2021GJ1 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	2010-04-03 16:15	> 1 w	0.1837208	0.1503551	0.2031572
EARTH	2021-04-01 06:44	< 1 min	0.1505747	0.1494182	0.0003855
EARTH	2032-03-29 22:20	> 1 w	0.1737143	0.1505597	0.1764225
EARTH	2118-04-03 22:38	> 1 mo	0.1601407	0.1505836	0.8887796

Download as:

Stationary Points

Ecc. an. ast.	Ecc. an. Earth	Distance in au	Classification
1.27740080	88.08827940	0.15011812	MINIMUM
182.41736719	269.60896591	0.84322360	MINIMUM
269.34170244	337.02652051	1.05611549	SADDLE
93.24069952	200.51292549	1.06857035	SADDLE
42.65251389	308.45303938	2.13175763	SADDLE
323.31670963	231.73110672	2.14123863	SADDLE
357.60286617	264.89618835	2.15001901	MAXIMUM
181.64941274	89.19314518	2.84292806	MAXIMUM

Download:

MOID Plots

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