Asteroids

2021JH help

Last update: 2024-04-25 23:56 UTC

Orbital Properties

Epoch

60400.0

MJD

Orbit type

Apollo

Perihelion (q)

0.876

Aphelion (Q)

3.642

Eccentricity (e)

0.612

Inclination (i)

0.4

deg

Orbit period (P)

1240.3

Earth MOID

0.00106

U parameter

9.0

Next Earth close approach

Date

2038-03-10

Nominal distance (from Earth center)

0.12503

18704359

Maximum Brightness

60.3

mag

Risk

Object is in risk list

Object is not in priority list

Physical Properties

Absolute Magnitude (H)

27.4

mag

Diameter

9 - 19*

Taxonomic type

Rotation period (T)

Discovery Information

Discovery Date

2021-05-01

Observatory

Mt. Lemmon Survey

Orbit Visualiser

Click the button to start Orbit Visualiser

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

60400.0000

1-sigma variation

Unit

MJD

Semimajor Axis

Value

2.259155

1-sigma variation

0.017880

Unit

Eccentricity (e)

Value

0.612310

1-sigma variation

0.003144

Unit

Inclination (i)

Value

0.4033

1-sigma variation

0.0016

Unit

Long. of Ascending Node (Ω)

Value

206.1092

1-sigma variation

0.0528

Unit

Arg. of Perihelion (ω)

Value

320.2499

1-sigma variation

0.0709

Unit

Mean Anomaly (M)

Value

320.87851

1-sigma variation

3.75000

Unit

Perihelion distance

Value

0.875853

1-sigma variation

Unit

Aphelion distance

Value

3.642458

1-sigma variation

Unit

Asc. Node-Earth Sep.

Value

-0.042160

1-sigma variation

Unit

Desc. Node-Earth Sep.

Value

1.662679

1-sigma variation

Unit

MOID

Value

0.001064

1-sigma variation

Unit

Orbit Period

Value

1240.2735

1-sigma variation

Unit

U parameter

Value

9.0

1-sigma variation

Unit

Covariance Matrix

	a	e	i	Ω	ω	M
a	3.19686E-4	5.61963E-5	2.14086E-5	-2.16799E-4	1.07353E-4	-6.70490E-2
e	5.61963E-5	9.88236E-6	3.82800E-6	-3.49598E-5	1.45266E-5	-1.17861E-2
i	2.14086E-5	3.82800E-6	2.55905E-6	3.99948E-5	-6.75593E-5	-4.48706E-3
Ω	-2.16799E-4	-3.49598E-5	3.99948E-5	2.79106E-3	-3.70267E-3	4.56187E-2
ω	1.07353E-4	1.45266E-5	-6.75593E-5	-3.70267E-3	5.02546E-3	-2.27205E-2
M	-6.70490E-2	-1.17861E-2	-4.48706E-3	4.56187E-2	-2.27205E-2	1.40625E1

Date of computation: 2024-04-23 10:08 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

27.448

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

9 - 19*

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 ODIM	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

0.9

Unit

Source

[1]

Unobserved

Value

1090

Unit

Source

[1]

Normalized RMS of residuals

Value

0.504005

Unit

Source

[1]

Astrometry Summary

First Observation
Last Observation
Total Optical Observations (Discarded)

Optical

Value

Unit

Source

First Observation

Value

2021-05-01.401534

Unit

Source

[2]

Last Observation

Value

2021-05-02.255377

Unit

Source

[2]

Total Optical Observations (Discarded)

Value

14 (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

[3]

Last Observation

Value

Unit

Source

[3]

Delay (Discarded)

Value

0 (0)

Unit

Source

[1]

Doppler (Discarded)

Value

0 (0)

Unit

Source

[1]

Total Radar Observations (Discarded)

Value

0 (0)

Unit

Source

[1]

Note: The ASCII file is in a format suitable for Orbfit input.

Sources

No.	Name	Additional
[1]	ESA ODIM	ESA orbit determination and impact monitoring system
[2]	MPC	Minor Planet Center: https://www.minorplanetcenter.net
[3]	JPL Radar Observations	Jet Propulsion Laboratory: https://ssd.jpl.nasa.gov/dat/radar_data_ast.txt

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 2021JH from 1950 to 2124

Body	Date in UTC	Time uncert. in min	Nominal distance in au	Min. possibile distance in au	Distance uncert. in au
EARTH	2001-04-29 17:29	> 1 mo	0.0341584	0.0007550	0.2871204
EARTH	2011-05-04 17:53	> 1 mo	0.0621140	0.0011968	0.6954571
EARTH	2021-04-28 07:06	5.0	0.0058884	0.0057958	0.0000309
EARTH	2038-03-10 15:46	> 1 mo	0.1250309	0.1029037	0.0177701
EARTH	2055-02-01 13:23	> 1 mo	0.0510672	0.0072371	1.3418166
EARTH	2072-01-26 10:32	> 1 mo	0.0157140	0.0073162	1.8428568
MARS	2086-01-29 12:02	> 1 mo	0.0367100	0.0351268	7.1207530
EARTH	2089-05-09 07:08	> 1 mo	0.1326660	0.0024644	39.5013110
EARTH	2113-02-22 20:50	> 1 mo	0.1124668	0.0135347	20.3544844

Download as:

2021JH

Date in UTC	MJD	σ	σ_imp	Distance ± Width in RE	Stretching in RE/σ	IP	Exp. energy	PS	TS
2117-01-22.204	94299.204	-0.439	0.000	0.95 ± 0.143	3.93E8	2.41E-9	1.24E-10	-10.09	0


Based on 14 optical observations (of which 0 are rejected as outliers) from 2021/05/01.402 to 2021/05/02.255.
Coordinates are given on the Target Plane.
Unit is one Earth radius, but impact cross section has radius between 1.32 and 1.32 Earth radii.
Coordinates for LOV = EQU scaled= 1 second= F.
AstOD software version= 4.0, Date of computation=20240110 090431.934 UTC.

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Download Impactor Table as: