Asteroids

2021DW1 help

Last update: 2025-07-29 02:36 UTC

Orbital Properties

Epoch

60800.0

MJD

Orbit type

Apollo

Perihelion (q)

0.992

Aphelion (Q)

1.662

Eccentricity (e)

0.253

Inclination (i)

6.9

deg

Orbit period (P)

558.4

Earth MOID

0.00339

U parameter

4.1

Next Earth close approach

Date

2047-02-20

Nominal distance (from Earth center)

0.05485

8205596

Maximum Brightness

21.2

mag

Risk

Object is not in risk list

Physical Properties

Absolute Magnitude (H)

mag

Diameter

27 - 60*

Taxonomic type

Rotation period (T)

Discovery Information

Discovery Date

2021-02-16

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

60800.0000

1-sigma variation

Unit

MJD

Semimajor Axis

Value

1.327127

1-sigma variation

0.000003

Unit

Eccentricity (e)

Value

0.252586

1-sigma variation

0.000002

Unit

Inclination (i)

Value

6.8772

1-sigma variation

4.569E-5

Unit

Long. of Ascending Node (Ω)

Value

162.4650

1-sigma variation

7.163E-6

Unit

Arg. of Perihelion (ω)

Value

10.5861

1-sigma variation

1.052E-5

Unit

Mean Anomaly (M)

Value

256.28657

1-sigma variation

0.00346

Unit

Perihelion distance

Value

0.991913

1-sigma variation

Unit

Aphelion distance

Value

1.662341

1-sigma variation

Unit

Asc. Node-Earth Sep.

Value

0.003681

1-sigma variation

Unit

Desc. Node-Earth Sep.

Value

0.644919

1-sigma variation

Unit

MOID

Value

0.003392

1-sigma variation

Unit

Orbit Period

Value

558.4280

1-sigma variation

Unit

U parameter

Value

4.1

1-sigma variation

Unit

Covariance Matrix

	a	e	i	Ω	ω	M
a	9.43098E-12	5.36711E-12	1.39997E-10	2.19093E-11	-6.46325E-12	-1.06306E-8
e	5.36711E-12	3.05441E-12	7.96716E-11	1.24689E-11	-3.63107E-12	-6.04982E-9
i	1.39997E-10	7.96716E-11	2.08751E-9	3.25650E-10	-9.39174E-11	-1.57806E-7
Ω	2.19093E-11	1.24689E-11	3.25650E-10	5.13064E-11	-1.45649E-11	-2.46966E-8
ω	-6.46325E-12	-3.63107E-12	-9.39174E-11	-1.45649E-11	1.10697E-10	7.22427E-9
M	-1.06306E-8	-6.04982E-9	-1.57806E-7	-2.46966E-8	7.22427E-9	1.19828E-5

Date of computation: 2025-07-29 02:36 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

24.962

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

27 - 60*

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

1613

Unit

Source

[1]

Normalized RMS of residuals

Value

0.617202

Unit

Source

[1]

Astrometry Summary

First Observation
Last Observation
Total Optical Observations (Discarded)

Optical

Value

Unit

Source

First Observation

Value

2021-02-16.237486

Unit

Source

[2]

Last Observation

Value

2021-03-15.49741

Unit

Source

[2]

Total Optical Observations (Discarded)

Value

298 (8)

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 2021DW1 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	1956-02-04 01:47	64.9	0.1950730	0.1927163	0.0007857
EARTH	1959-02-25 04:46	38.7	0.0292296	0.0288351	0.0001315
EARTH	1962-03-18 22:29	272.7	0.0453488	0.0436339	0.0005722
EARTH	1965-04-17 22:18	111.2	0.1577791	0.1556864	0.0006986
EARTH	2018-02-11 08:11	8.8	0.1179113	0.1177078	0.0000678
EARTH	2021-03-04 08:57	< 1 s	0.0038099	0.0038098	0.0000000
EARTH	2047-02-20 05:20	115.6	0.0548510	0.0533437	0.0005025
EARTH	2076-02-12 17:51	401.4	0.1130474	0.1039560	0.0030331
EARTH	2079-04-18 12:46	475.0	0.1377216	0.1308288	0.0023155
EARTH	2108-03-27 06:51	1287.7	0.0629695	0.0553258	0.0025753

Download as:

Stationary Points

Ecc. an. ast.	Ecc. an. Earth	Distance in au	Classification
352.28041399	60.01720315	0.00339243	MINIMUM
183.11857785	253.67626497	0.65824895	SADDLE
3.89287148	254.83145914	1.99642461	SADDLE
181.79605614	72.65287189	2.65689619	MAXIMUM

Download:

MOID Plots

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