Asteroids

436724 2011UW158 help

Last update: 2026-07-30 09:40 UTC

Orbital Properties

Epoch

61200.0

MJD

Orbit type

Apollo

Perihelion (q)

1.010

Aphelion (Q)

2.231

Eccentricity (e)

0.377

Inclination (i)

4.6

deg

Orbit period (P)

753.4

Earth MOID

0.00303

U parameter

0.0

Next Earth close approach

Date

2048-08-05

Nominal distance (from Earth center)

0.04316

6456105

Maximum Brightness

15.9

mag

Risk

Object is not in risk list

Physical Properties

Absolute Magnitude (H)

mag

Diameter

600 | 300

Taxonomic type

Rotation period (T)

0.6108

Discovery Information

Discovery Date

2011-10-25

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

61200.0000

1-sigma variation

Unit

MJD

Semimajor Axis

Value

1.620439

1-sigma variation

8.587E-9

Unit

Eccentricity (e)

Value

0.376639

1-sigma variation

4.682E-9

Unit

Inclination (i)

Value

4.5732

1-sigma variation

9.105E-7

Unit

Long. of Ascending Node (Ω)

Value

285.9402

1-sigma variation

2.003E-6

Unit

Arg. of Perihelion (ω)

Value

8.8291

1-sigma variation

4.182E-6

Unit

Mean Anomaly (M)

Value

100.78535

1-sigma variation

0.00002

Unit

Perihelion distance

Value

1.010119

1-sigma variation

Unit

Aphelion distance

Value

2.230758

1-sigma variation

Unit

Asc. Node-Earth Sep.

Value

-0.003457

1-sigma variation

Unit

Desc. Node-Earth Sep.

Value

1.231494

1-sigma variation

Unit

MOID

Value

0.003026

1-sigma variation

Unit

Orbit Period

Value

753.4376

1-sigma variation

Unit

U parameter

Value

0.0

1-sigma variation

Unit

Covariance Matrix

	a	e	i	Ω	ω	M
a	7.37322E-17	2.24072E-17	-8.91275E-17	-2.43630E-15	1.11875E-15	-1.28942E-13
e	2.24072E-17	2.19186E-17	-2.27295E-15	-1.62022E-15	-1.54186E-15	-3.78028E-14
i	-8.91275E-17	-2.27295E-15	8.29064E-13	1.47426E-12	-3.09818E-13	-3.73461E-13
Ω	-2.43630E-15	-1.62022E-15	1.47426E-12	4.01280E-12	-5.18198E-13	2.77980E-12
ω	1.11875E-15	-1.54186E-15	-3.09818E-13	-5.18198E-13	1.74879E-11	-9.04362E-12
M	-1.28942E-13	-3.78028E-14	-3.73461E-13	2.77980E-12	-9.04362E-12	2.29086E-10

Date of computation: 2026-07-30 09:40 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

0.6108

Unit

Source

[2]

Quality

Value

Unit

Source

[2]

Amplitude

Value

0.68

Unit

mag

Source

[2]

Rotation Direction

Value

Unit

Source

[-]

Spinvector L

Value

290

Unit

Source

[1]

Spinvector B

Value

-39

Unit

Source

[1]

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

19.93

19.951

Unit

mag

Source

[3]

[4]

Slope Parameter (G)

Value

0.15**

0.023

Unit

Source

[4]

[3]

Albedo
Diameter

Size and albedo

Value

Unit

Source

Albedo

Value

0.05 - 0.25

Unit

Source

[-]

Diameter

Value

600 | 300

Unit

Source

[5]

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

[6]

Download this part as:

Sources

No.	Name	Additional
[1]	EARN	1.) Carbognani, A. et al. (2016) MPB 43, 38-41. (POLE AND SHAPE FOR THE NEA (436724) 2011 UW158)
[2]	EARN	1.) Carbognani, A. et al. (2016) MPB 43, 38-41. (POLE AND SHAPE FOR THE NEA (436724) 2011 UW158) 2.) Gary, B.L. (2016) MPB 43, 33-38. (UNUSUAL PROPERTIES FOR THE NEA (436724) 2011 UW158) 3.) Warner, B.D. (2016) MPB 43, 66-79. (NEAR-EARTH ASTEROID LIGHTCURVE ANALYSIS AT CS3-PALMER DIVIDE STATION: 2015 JUNE-SEPTEMBER)(36 NEAs)
[3]	EARN	1.) Gary, B.L. (2016) MPB 43, 33-38. (UNUSUAL PROPERTIES FOR THE NEA (436724) 2011 UW158)
[4]	ESA Aegis	ESA orbit determination and impact monitoring system
[5]	EARN	1.) Naidu. S.P. et al. (2015) DPS47-204.08. (astract) (Radar observations of near-Earth asteroid (436724) 2011 UW158 using the Arecibo, Goldstone, and Green Bank)
[6]	EARN	1.) href="http://echo.jpl.nasa.gov/asteroids/index.html">JPL's NEO Radar Detection Program Webpage 2.) Naidu. S.P. et al. (2015) DPS47-204.08. (astract) (Radar observations of near-Earth asteroid (436724) 2011 UW158 using the Arecibo, Goldstone, and Green Bank)

Observational Information

Arc Length
Unobserved
Normalized RMS of residuals

Arc Information

Value

Unit

Source

Arc Length

Value

4878

Unit

Source

[1]

Unobserved

Value

566

Unit

Source

[1]

Normalized RMS of residuals

Value

0.340959

Unit

Source

[1]

Astrometry Summary

First Observation
Last Observation
Total Optical Observations (Discarded)

Optical

Value

Unit

Source

First Observation

Value

2011-10-25.4186

Unit

Source

[2]

Last Observation

Value

2025-03-03.273927

Unit

Source

[2]

Total Optical Observations (Discarded)

Value

957 (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

2015-07-13

Unit

Source

[3]

Last Observation

Value

2015-07-26

Unit

Source

[3]

Delay (Discarded)

Value

8 (0)

Unit

Source

[1]

Doppler (Discarded)

Value

0 (0)

Unit

Source

[-]

Total Radar Observations (Discarded)

Value

8 (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

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Max residual (arcsec):

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Note: Ephemerides requests are limited to a maximum of 1000 points and a final date not exceeding 2040/12/31 00:00.

Close Approaches for 436724 2011UW158 from 1950 to 2126

Body	Date in UTC	Time uncert. in min	Nominal distance in au	Min. possible distance in au	Distance uncert. in au
EARTH	1978-07-01 10:00	< 1 min	0.0120172	0.0120144	0.0000009
EARTH	2015-07-19 14:36	< 1 s	0.0164401	0.0164401	0.0000000
EARTH	2048-08-05 04:24	< 1 min	0.0431564	0.0431538	0.0000009
EARTH	2079-08-17 17:25	< 1 min	0.0816648	0.0816609	0.0000013
EARTH	2108-07-02 08:57	< 1 min	0.0109363	0.0109362	0.0000000

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Stationary Points

Ecc. an. ast.	Ecc. an. Earth	Distance in au	Classification
353.33856818	180.49008507	0.00302565	MINIMUM
179.92337188	10.20937066	1.24711869	SADDLE
359.66707204	10.00380839	1.99384835	SADDLE
179.77100395	190.10545198	3.24728554	MAXIMUM

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MOID Plots

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