Asteroids

2020OR4 help

Last update: 2026-07-30 14:25 UTC

Orbital Properties

Epoch

61200.0

MJD

Orbit type

Apollo

Perihelion (q)

0.565

Aphelion (Q)

4.430

Eccentricity (e)

0.774

Inclination (i)

1.0

deg

Orbit period (P)

1441.3

Earth MOID

0.00183

U parameter

8.2

Next Earth close approach

Date

2084-08-07

Nominal distance (from Earth center)

0.03743

5599017

Maximum Brightness

21.8

mag

Risk

Object is in risk list

Physical Properties

Absolute Magnitude (H)

25.5

mag

Diameter

21 - 50*

Taxonomic type

Rotation period (T)

Discovery Information

Discovery Date

2020-07-26

Observatory

University of Arizona 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

2.497068

1-sigma variation

0.005348

Unit

Eccentricity (e)

Value

0.773924

1-sigma variation

0.000563

Unit

Inclination (i)

Value

0.9555

1-sigma variation

0.0009

Unit

Long. of Ascending Node (Ω)

Value

119.4010

1-sigma variation

0.0026

Unit

Arg. of Perihelion (ω)

Value

277.5805

1-sigma variation

0.0032

Unit

Mean Anomaly (M)

Value

163.01611

1-sigma variation

1.70243

Unit

Perihelion distance

Value

0.564527

1-sigma variation

Unit

Aphelion distance

Value

4.429609

1-sigma variation

Unit

Asc. Node-Earth Sep.

Value

-0.076392

1-sigma variation

Unit

Desc. Node-Earth Sep.

Value

0.100547

1-sigma variation

Unit

MOID

Value

0.001825

1-sigma variation

Unit

Orbit Period

Value

1441.2657

1-sigma variation

Unit

U parameter

Value

8.2

1-sigma variation

Unit

Covariance Matrix

	a	e	i	Ω	ω	M
a	2.86008E-5	3.00908E-6	4.95777E-6	1.40576E-5	-1.72569E-5	-9.10453E-3
e	3.00908E-6	3.16588E-7	5.21526E-7	1.47897E-6	-1.81515E-6	-9.57887E-4
i	4.95777E-6	5.21526E-7	8.63424E-7	2.44194E-6	-3.01235E-6	-1.57822E-3
Ω	1.40576E-5	1.47897E-6	2.44194E-6	6.92964E-6	-8.50834E-6	-4.47497E-3
ω	-1.72569E-5	-1.81515E-6	-3.01235E-6	-8.50834E-6	1.05303E-5	5.49344E-3
M	-9.10453E-3	-9.57887E-4	-1.57822E-3	-4.47497E-3	5.49344E-3	2.89826E0

Date of computation: 2026-07-30 14:25 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

25.545

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

21 - 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

[-]

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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

2232

Unit

Source

[1]

Normalized RMS of residuals

Value

0.392456

Unit

Source

[1]

Astrometry Summary

First Observation
Last Observation
Total Optical Observations (Discarded)

Optical

Value

Unit

Source

First Observation

Value

2020-07-20.399226

Unit

Source

[2]

Last Observation

Value

2020-07-26.983404

Unit

Source

[2]

Total Optical Observations (Discarded)

Value

44 (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

Filters

Initial Date: *

Final Date: *

Normalised Only accepted

Max residual (arcsec):

* - these fields are required

Plot

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 2020OR4 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	2005-02-05 16:10	> 1 mo	0.1528992	0.0032395	24.3820900
EARTH	2016-07-27 03:04	> 1 d	0.0017928	0.0014084	0.0496087
EARTH	2020-07-28 20:53	< 1 min	0.0030583	0.0030518	0.0000022
EARTH	2084-08-07 16:47	> 1 w	0.0374271	0.0037759	0.4269470
EARTH	2101-01-22 10:57	> 1 mo	0.0268180	0.0001159	1.8880462

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Stationary Points

Ecc. an. ast.	Ecc. an. Earth	Distance in au	Classification
38.49634718	20.96369055	0.00182540	MINIMUM
320.04481492	201.88992562	0.00194982	MINIMUM
358.70872252	290.53801702	0.42958289	SADDLE
358.69555637	110.51983678	1.57065787	SADDLE
179.83526010	112.32099921	3.42336218	SADDLE
179.83812110	292.32455195	5.42319204	MAXIMUM

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MOID Plots

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

Level lines of the squared distance function

2020OR4

Date in UTC	MJD	σ	Distance ± Width in RE	Stretching in RE	IP	Impact energy	PS
2093-01-20.131	85532.131	0.973	1.02 ± 0.002	8.75E4	4.61E-6	1.47E0	-5.51
2093-01-20.651	85532.651	1.450	0.48 ± 0.002	8.31E6	3.47E-8	1.49E0	-7.63
2097-01-20.155	86993.155	0.974	0.79 ± 0.002	8.11E6	6.90E-8	1.48E0	-7.36
2097-01-20.675	86993.675	1.415	1.08 ± 0.003	3.92E5	2.31E-7	1.49E0	-6.83
2101-01-20.385	88453.385	-0.350	0.43 ± 0.002	4.62E6	1.70E-7	1.43E0	-7.00
2101-01-21.573	88454.573	1.195	0.72 ± 0.003	5.36E6	6.31E-8	1.48E0	-7.42
2101-01-21.668	88454.668	1.211	0.75 ± 0.002	1.20E6	3.42E-7	1.48E0	-6.68
2105-01-21.191	89915.191	0.812	0.70 ± 0.002	2.36E6	2.15E-7	1.47E0	-6.91
2105-01-21.208	89915.208	0.852	0.20 ± 0.002	2.10E5	2.94E-6	1.47E0	-5.77
2105-01-21.658	89915.658	1.424	0.74 ± 0.003	1.93E6	1.29E-7	1.48E0	-7.13
2109-01-19.869	91374.869	-0.786	0.82 ± 0.002	3.66E6	1.26E-7	1.40E0	-7.18
2109-01-21.214	91376.214	0.853	0.42 ± 0.002	8.82E6	6.76E-8	1.46E0	-7.43
2109-01-21.245	91376.245	0.870	1.03 ± 0.002	3.60E5	6.88E-7	1.47E0	-6.43
2109-01-21.280	91376.280	3.756	0.37 ± 0.001	4.97E6	1.49E-10	1.50E0	-10.08
2113-01-20.205	92836.205	-0.788	1.03 ± 0.001	4.08E6	6.63E-8	1.41E0	-7.48
2113-01-20.575	92836.575	-0.353	1.00 ± 0.002	2.32E6	1.68E-7	1.43E0	-7.07
2113-01-21.239	92837.239	3.780	0.60 ± 0.001	3.86E6	1.59E-10	1.50E0	-10.07
2117-01-18.841	94295.841	-1.488	1.11 ± 0.003	8.95E7	6.86E-10	1.37E0	-9.49
2117-01-20.104	94297.104	-0.789	0.67 ± 0.001	3.56E6	1.54E-7	1.40E0	-7.13
2117-01-20.481	94297.481	-0.352	0.30 ± 0.002	5.95E6	1.37E-7	1.42E0	-7.17
2118-01-21.024	94663.024	-0.752	0.75 ± 0.003	6.64E7	9.88E-9	1.43E0	-8.32
2121-01-20.452	95758.452	-0.352	0.22 ± 0.006	1.15E7	7.37E-8	1.42E0	-7.46
2121-01-20.698	95758.698	-0.083	0.97 ± 0.002	1.80E6	3.11E-7	1.43E0	-6.84


Based on 44 optical observations (of which 0 are rejected as outliers) from 2020/07/20.399 to 2020/07/26.983.
Coordinates are given on the Target Plane.
Unit is one Earth radius, but impact cross section has radius between 1.13 and 1.13 Earth radii.
Coordinates for LOV = EQU scaled= 1 second= F.
AstOD software version= 4.0, Date of computation=20250805 130500.123 UTC.

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