Asteroids

2021FH1 help

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

Orbital Properties

Epoch

61000.0

MJD

Orbit type

Apollo

Perihelion (q)

0.804

Aphelion (Q)

1.619

Eccentricity (e)

0.336

Inclination (i)

18.2

deg

Orbit period (P)

487.0

Earth MOID

0.00915

U parameter

0.0

Next Earth close approach

Date

2029-03-21

Nominal distance (from Earth center)

0.01008

1507247

Maximum Brightness

16.5

mag

Risk

Object is not in risk list

Physical Properties

Absolute Magnitude (H)

25.2

mag

Diameter

24 - 50*

Taxonomic type

Rotation period (T)

Discovery Information

Discovery Date

2021-03-19

Observatory

Catalina Sky 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

1.211366

1-sigma variation

2.896E-9

Unit

Eccentricity (e)

Value

0.336451

1-sigma variation

2.996E-7

Unit

Inclination (i)

Value

18.1644

1-sigma variation

1.868E-5

Unit

Long. of Ascending Node (Ω)

Value

179.5337

1-sigma variation

8.215E-7

Unit

Arg. of Perihelion (ω)

Value

79.1599

1-sigma variation

0.0001

Unit

Mean Anomaly (M)

Value

138.00439

1-sigma variation

0.00001

Unit

Perihelion distance

Value

0.803800

1-sigma variation

Unit

Aphelion distance

Value

1.618932

1-sigma variation

Unit

Asc. Node-Earth Sep.

Value

0.013270

1-sigma variation

Unit

Desc. Node-Earth Sep.

Value

0.142717

1-sigma variation

Unit

MOID

Value

0.009150

1-sigma variation

Unit

Orbit Period

Value

486.9805

1-sigma variation

Unit

U parameter

Value

0.0

1-sigma variation

Unit

Covariance Matrix

	a	e	i	Ω	ω	M
a	8.38555E-18	4.35987E-16	1.13842E-14	1.46308E-16	7.58782E-14	-1.64171E-14
e	4.35987E-16	8.97764E-14	1.76392E-12	6.77285E-14	1.58316E-11	-3.13900E-12
i	1.13842E-14	1.76392E-12	3.48892E-10	-1.54633E-12	3.32609E-10	-7.56495E-11
Ω	1.46308E-16	6.77285E-14	-1.54633E-12	6.74823E-13	1.09267E-11	-2.02727E-12
ω	7.58782E-14	1.58316E-11	3.32609E-10	1.09267E-11	2.79644E-9	-5.55821E-10
M	-1.64171E-14	-3.13900E-12	-7.56495E-11	-2.02727E-12	-5.55821E-10	1.11533E-10

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

25.234

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

24 - 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

2937

Unit

Source

[1]

Unobserved

Value

239

Unit

Source

[1]

Normalized RMS of residuals

Value

0.668867

Unit

Source

[1]

Astrometry Summary

First Observation
Last Observation
Total Optical Observations (Discarded)

Optical

Value

Unit

Source

First Observation

Value

2017-03-07.406502

Unit

Source

[2]

Last Observation

Value

2025-03-22.060359

Unit

Source

[2]

Total Optical Observations (Discarded)

Value

199 (10)

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 2021FH1 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	1969-09-13 22:01	< 1 s	0.1515943	0.1515890	0.0000018
EARTH	1973-09-11 14:46	< 1 min	0.1007694	0.1007663	0.0000010
EARTH	1977-09-09 22:45	< 1 min	0.0950174	0.0950171	0.0000001
EARTH	1981-09-08 23:16	< 1 min	0.1317665	0.1317640	0.0000008
EARTH	1985-09-09 07:41	< 1 min	0.1886150	0.1886117	0.0000011
EARTH	2009-03-30 10:37	< 1 min	0.1626197	0.1626194	0.0000001
EARTH	2013-03-26 05:23	< 1 s	0.0922529	0.0922527	0.0000001
EARTH	2017-03-22 23:51	< 1 s	0.0314022	0.0314021	0.0000001
EARTH	2021-03-21 16:24	< 1 s	0.0104609	0.0104609	0.0000000
EARTH	2025-03-21 13:30	< 1 s	0.0099556	0.0099556	0.0000000
EARTH	2029-03-21 11:43	< 1 s	0.0100753	0.0100753	0.0000000
EARTH	2033-03-20 13:05	< 1 min	0.0234540	0.0234505	0.0000012
EARTH	2037-03-17 09:25	< 1 min	0.0890929	0.0890911	0.0000006
EARTH	2041-03-13 15:18	< 1 s	0.1713577	0.1713571	0.0000002
EARTH	2082-09-15 11:19	< 1 min	0.1574890	0.1574706	0.0000061
EARTH	2086-09-12 20:53	< 1 min	0.0988726	0.0988608	0.0000039
EARTH	2090-09-10 22:14	< 1 min	0.0875897	0.0875846	0.0000017
EARTH	2094-09-09 16:36	< 1 min	0.1272853	0.1272669	0.0000061
EARTH	2098-09-09 17:01	< 1 min	0.1893393	0.1893144	0.0000083
EARTH	2122-03-31 06:39	1.0	0.1547421	0.1547012	0.0000136

Download as:

Stationary Points

Ecc. an. ast.	Ecc. an. Earth	Distance in au	Classification
300.70502395	77.62541273	0.00980186	MINIMUM
68.80792314	246.24348179	0.09034157	MINIMUM
5.92213043	164.40036355	0.35411186	SADDLE
183.81286629	338.94615010	0.74609696	SADDLE
2.39971415	339.05463510	1.76701785	SADDLE
179.47384873	155.77594639	2.60380701	MAXIMUM

Download:

MOID Plots

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