Asteroids

2021TF13 help

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

Orbital Properties

Epoch

61000.0

MJD

Orbit type

Apollo

Perihelion (q)

0.688

Aphelion (Q)

3.153

Eccentricity (e)

0.642

Inclination (i)

8.7

deg

Orbit period (P)

972.4

Earth MOID

0.01754

U parameter

8.2

Next Earth close approach

Date

2029-10-10

Nominal distance (from Earth center)

0.10285

15385577

Maximum Brightness

24.3

mag

Risk

Object is not in risk list

Physical Properties

Absolute Magnitude (H)

26.3

mag

Diameter

15 - 30*

Taxonomic type

Rotation period (T)

Discovery Information

Discovery Date

2021-10-13

Observatory

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

61000.0000

1-sigma variation

Unit

MJD

Semimajor Axis

Value

1.920862

1-sigma variation

0.003286

Unit

Eccentricity (e)

Value

0.641586

1-sigma variation

0.000714

Unit

Inclination (i)

Value

8.6674

1-sigma variation

0.0092

Unit

Long. of Ascending Node (Ω)

Value

17.0982

1-sigma variation

0.0007

Unit

Arg. of Perihelion (ω)

Value

84.8934

1-sigma variation

0.0030

Unit

Mean Anomaly (M)

Value

176.84523

1-sigma variation

1.37154

Unit

Perihelion distance

Value

0.688465

1-sigma variation

Unit

Aphelion distance

Value

3.153260

1-sigma variation

Unit

Asc. Node-Earth Sep.

Value

0.070407

1-sigma variation

Unit

Desc. Node-Earth Sep.

Value

0.196197

1-sigma variation

Unit

MOID

Value

0.017540

1-sigma variation

Unit

Orbit Period

Value

972.3951

1-sigma variation

Unit

U parameter

Value

8.2

1-sigma variation

Unit

Covariance Matrix

	a	e	i	Ω	ω	M
a	1.07973E-5	2.34505E-6	3.02227E-5	2.14914E-6	-9.95711E-6	-4.50676E-3
e	2.34505E-6	5.09320E-7	6.56404E-6	4.66771E-7	-2.16254E-6	-9.78821E-4
i	3.02227E-5	6.56404E-6	8.45970E-5	6.01565E-6	-2.78716E-5	-1.26149E-2
Ω	2.14914E-6	4.66771E-7	6.01565E-6	4.27839E-7	-1.98171E-6	-8.97046E-4
ω	-9.95711E-6	-2.16254E-6	-2.78716E-5	-1.98171E-6	9.18899E-6	4.15608E-3
M	-4.50676E-3	-9.78821E-4	-1.26149E-2	-8.97046E-4	4.15608E-3	1.88111E0

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

26.287

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

15 - 30*

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

1442

Unit

Source

[1]

Normalized RMS of residuals

Value

0.898501

Unit

Source

[1]

Astrometry Summary

First Observation
Last Observation
Total Optical Observations (Discarded)

Optical

Value

Unit

Source

First Observation

Value

2021-10-02.401821

Unit

Source

[2]

Last Observation

Value

2021-10-14.85308

Unit

Source

[2]

Total Optical Observations (Discarded)

Value

29 (1)

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 2021TF13 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	2005-10-29 02:14	> 1 w	0.1425825	0.0084312	0.1324688
EARTH	2013-10-17 20:38	> 1 w	0.0243693	0.0151535	0.1006975
EARTH	2021-10-16 13:40	< 1 min	0.0191719	0.0191113	0.0000202
EARTH	2029-10-10 21:34	> 1 w	0.1028462	0.0166345	0.1274065
MARS	2069-07-31 00:46	> 1 w	0.0389424	0.0356356	0.0965853

Download as:

Stationary Points

Ecc. an. ast.	Ecc. an. Earth	Distance in au	Classification
318.27334644	282.18469525	0.01757255	MINIMUM
42.12261186	78.00378363	0.04320288	MINIMUM
0.41873144	0.58446214	0.32018444	SADDLE
0.07739854	179.86288904	1.70010172	SADDLE
180.06415866	179.72087124	2.15378530	SADDLE
179.96448837	359.67357891	4.12828082	MAXIMUM

Download:

MOID Plots

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