Asteroids

2015LR21 help

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

Orbital Properties

Epoch

61000.0

MJD

Orbit type

Apollo

Perihelion (q)

0.823

Aphelion (Q)

2.993

Eccentricity (e)

0.569

Inclination (i)

1.9

deg

Orbit period (P)

962.4

Earth MOID

0.00094

U parameter

4.2

Next Earth close approach

Date

2036-09-29

Nominal distance (from Earth center)

0.13163

19691119

Maximum Brightness

27.9

mag

Risk

Object is not in risk list

Physical Properties

Absolute Magnitude (H)

26.5

mag

Diameter

13 - 30*

Taxonomic type

Rotation period (T)

Discovery Information

Discovery Date

2015-06-15

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

1.907679

1-sigma variation

0.000007

Unit

Eccentricity (e)

Value

0.568756

1-sigma variation

0.000002

Unit

Inclination (i)

Value

1.8891

1-sigma variation

1.271E-5

Unit

Long. of Ascending Node (Ω)

Value

86.3181

1-sigma variation

1.510E-5

Unit

Arg. of Perihelion (ω)

Value

243.3831

1-sigma variation

0.0001

Unit

Mean Anomaly (M)

Value

327.85048

1-sigma variation

0.00781

Unit

Perihelion distance

Value

0.822676

1-sigma variation

Unit

Aphelion distance

Value

2.992682

1-sigma variation

Unit

Asc. Node-Earth Sep.

Value

0.745796

1-sigma variation

Unit

Desc. Node-Earth Sep.

Value

0.011653

1-sigma variation

Unit

MOID

Value

0.000939

1-sigma variation

Unit

Orbit Period

Value

962.4019

1-sigma variation

Unit

U parameter

Value

4.2

1-sigma variation

Unit

Covariance Matrix

	a	e	i	Ω	ω	M
a	4.80652E-11	1.12746E-11	7.87592E-12	1.24539E-11	-3.78787E-10	-5.41236E-8
e	1.12746E-11	2.65323E-12	1.73125E-12	3.10144E-12	-8.63910E-11	-1.26961E-8
i	7.87592E-12	1.73125E-12	1.61520E-10	-1.75806E-11	-7.43245E-11	-8.86494E-9
Ω	1.24539E-11	3.10144E-12	-1.75806E-11	2.28058E-10	-2.72380E-10	-1.40296E-8
ω	-3.78787E-10	-8.63910E-11	-7.43245E-11	-2.72380E-10	3.92475E-9	4.26420E-7
M	-5.41236E-8	-1.26961E-8	-8.86494E-9	-1.40296E-8	4.26420E-7	6.09456E-5

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

26.487

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

13 - 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

Radar R

Unit

Source

[3]

Download this part as:

Sources

No.	Name	Additional
[1]	ESA Aegis	ESA orbit determination and impact monitoring system
[2]	Estimation	Estimated from absolute magnitude
[3]	EARN	1.) href="http://echo.jpl.nasa.gov/asteroids/index.html">JPL's NEO Radar Detection Program Webpage

Observational Information

Arc Length
Unobserved
Normalized RMS of residuals

Arc Information

Value

Unit

Source

Arc Length

Value

Unit

Source

[1]

Unobserved

Value

3751

Unit

Source

[1]

Normalized RMS of residuals

Value

0.463462

Unit

Source

[1]

Astrometry Summary

First Observation
Last Observation
Total Optical Observations (Discarded)

Optical

Value

Unit

Source

First Observation

Value

2015-06-11.36395

Unit

Source

[2]

Last Observation

Value

2015-06-20.16244

Unit

Source

[2]

Total Optical Observations (Discarded)

Value

52 (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

2015-06-20

Unit

Source

[3]

Last Observation

Value

2015-06-20

Unit

Source

[3]

Delay (Discarded)

Value

1 (0)

Unit

Source

[1]

Doppler (Discarded)

Value

1 (0)

Unit

Source

[1]

Total Radar Observations (Discarded)

Value

2 (0)

Unit

Source

[1]

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
[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 2015LR21 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	1950-06-25 15:50	> 1 d	0.0609606	0.0003402	0.0234339
EARTH	1955-06-19 01:26	4.9	0.0015212	0.0014316	0.0000299
EARTH	1968-08-01 00:35	147.6	0.1795393	0.1792417	0.0000992
EARTH	1981-09-20 10:55	226.0	0.1572152	0.1563786	0.0002789
EARTH	1994-10-29 02:08	64.1	0.0856973	0.0838575	0.0006141
EARTH	2015-06-20 06:14	< 1 s	0.0065449	0.0065449	0.0000000
EARTH	2036-09-29 14:32	221.0	0.1316270	0.1303152	0.0004374
EARTH	2044-06-15 01:48	88.8	0.0486101	0.0462713	0.0007796
EARTH	2065-08-12 04:29	1230.0	0.1870732	0.1859333	0.0003801
EARTH	2086-10-18 02:46	1359.5	0.0544293	0.0370122	0.0063606
EARTH	2094-06-16 05:58	582.2	0.0479937	0.0325376	0.0051540
EARTH	2107-10-29 21:02	> 1 d	0.0688680	0.0345761	0.0128073
EARTH	2115-06-25 12:36	> 1 d	0.0329588	0.0021255	0.0144332

Download as:

Stationary Points

Ecc. an. ast.	Ecc. an. Earth	Distance in au	Classification
325.26730081	165.61303426	0.00111272	MINIMUM
32.85103634	287.08190225	0.02779989	MINIMUM
358.99328148	226.37178016	0.19036587	SADDLE
358.84888484	46.07363134	1.81110211	SADDLE
179.69053798	47.07051721	2.00421934	SADDLE
179.65611396	227.04745076	4.00305693	MAXIMUM

Download:

MOID Plots

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