Asteroids

2021RD2 help

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

Orbital Properties

Epoch

61000.0

MJD

Orbit type

Apollo

Perihelion (q)

0.553

Aphelion (Q)

2.285

Eccentricity (e)

0.610

Inclination (i)

43.9

deg

Orbit period (P)

617.2

Earth MOID

0.09407

U parameter

9.0

Next Earth close approach

Date

2043-09-13

Nominal distance (from Earth center)

0.16064

24030794

Maximum Brightness

21.9

mag

Risk

Object is not in risk list

Physical Properties

Absolute Magnitude (H)

23.1

mag

Diameter

60 - 140*

Taxonomic type

Rotation period (T)

Discovery Information

Discovery Date

2021-09-05

Observatory

Pan-STARRS 2, 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

1.418694

1-sigma variation

0.004911

Unit

Eccentricity (e)

Value

0.610403

1-sigma variation

0.001224

Unit

Inclination (i)

Value

43.9013

1-sigma variation

0.1108

Unit

Long. of Ascending Node (Ω)

Value

170.8694

1-sigma variation

0.0033

Unit

Arg. of Perihelion (ω)

Value

291.4495

1-sigma variation

0.1086

Unit

Mean Anomaly (M)

Value

132.54019

1-sigma variation

4.38855

Unit

Perihelion distance

Value

0.552719

1-sigma variation

Unit

Aphelion distance

Value

2.284669

1-sigma variation

Unit

Asc. Node-Earth Sep.

Value

-0.266873

1-sigma variation

Unit

Desc. Node-Earth Sep.

Value

0.139240

1-sigma variation

Unit

MOID

Value

0.094074

1-sigma variation

Unit

Orbit Period

Value

617.2080

1-sigma variation

Unit

U parameter

Value

9.0

1-sigma variation

Unit

Covariance Matrix

	a	e	i	Ω	ω	M
a	2.41171E-5	6.00898E-6	5.43943E-4	-1.59761E-5	-5.33285E-4	-2.15518E-2
e	6.00898E-6	1.49719E-6	1.35527E-4	-3.98057E-6	-1.32872E-4	-5.36981E-3
i	5.43943E-4	1.35527E-4	1.22684E-2	-3.60330E-4	-1.20278E-2	-4.86084E-1
Ω	-1.59761E-5	-3.98057E-6	-3.60330E-4	1.05833E-5	3.53267E-4	1.42767E-2
ω	-5.33285E-4	-1.32872E-4	-1.20278E-2	3.53267E-4	1.17922E-2	4.76559E-1
M	-2.15518E-2	-5.36981E-3	-4.86084E-1	1.42767E-2	4.76559E-1	1.92594E1

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

23.121

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

60 - 140*

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

1513

Unit

Source

[1]

Normalized RMS of residuals

Value

0.488112

Unit

Source

[1]

Astrometry Summary

First Observation
Last Observation
Total Optical Observations (Discarded)

Optical

Value

Unit

Source

First Observation

Value

2021-09-05.336902

Unit

Source

[2]

Last Observation

Value

2021-09-15.14717

Unit

Source

[2]

Total Optical Observations (Discarded)

Value

32 (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 2021RD2 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	1972-09-19 22:29	> 1 mo	0.1192419	0.0910146	1.1775748
EARTH	1994-09-12 13:50	> 1 mo	0.1771726	0.0910969	1.0868608
VENUS	2006-10-02 23:50	> 1 w	0.0361622	0.0308610	0.3577429
VENUS	2013-07-08 09:14	> 1 w	0.0356033	0.0307395	0.1553577
EARTH	2021-09-20 07:00	< 1 min	0.1229813	0.1221495	0.0002773
EARTH	2043-09-13 16:38	> 1 w	0.1606359	0.0938237	0.4931230
EARTH	2070-09-19 00:33	> 1 mo	0.1006152	0.0963605	0.3339954
EARTH	2119-09-18 23:31	> 1 mo	0.0993211	0.0985588	0.2169191

Download as:

Stationary Points

Ecc. an. ast.	Ecc. an. Earth	Distance in au	Classification
293.80849376	253.46613266	0.09456890	MINIMUM
44.97030716	75.92445052	0.22764016	MINIMUM
349.88397524	340.82875180	0.69746527	SADDLE
353.71823290	171.01218617	1.47283685	SADDLE
171.00048668	181.66031067	1.65645070	SADDLE
185.70183707	10.74701874	3.10565882	MAXIMUM

Download:

MOID Plots

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