Asteroids

8013 Gordonmoore help

Last update: 2026-07-15 14:31 UTC

Orbital Properties

Epoch

61200.0

MJD

Orbit type

Amor

Perihelion (q)

1.249

Aphelion (Q)

3.150

Eccentricity (e)

0.432

Inclination (i)

7.6

deg

Orbit period (P)

1191.5

Earth MOID

0.24514

U parameter

0.0

Next Earth close approach

Date

Nominal distance (from Earth center)

Maximum Brightness

mag

Risk

Object is not in risk list

Physical Properties

Absolute Magnitude (H)

17.1

mag

Diameter

1200

Taxonomic type

Rotation period (T)

8.400

Discovery Information

Discovery Date

1990-05-18

Observatory

Palomar Mountain

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

2.199592

1-sigma variation

2.784E-9

Unit

Eccentricity (e)

Value

0.432146

1-sigma variation

2.279E-8

Unit

Inclination (i)

Value

7.5978

1-sigma variation

2.842E-6

Unit

Long. of Ascending Node (Ω)

Value

105.3409

1-sigma variation

2.903E-5

Unit

Arg. of Perihelion (ω)

Value

147.4112

1-sigma variation

2.970E-5

Unit

Mean Anomaly (M)

Value

11.67933

1-sigma variation

0.00001

Unit

Perihelion distance

Value

1.249047

1-sigma variation

Unit

Aphelion distance

Value

3.150136

1-sigma variation

Unit

Asc. Node-Earth Sep.

Value

1.829890

1-sigma variation

Unit

Desc. Node-Earth Sep.

Value

0.294434

1-sigma variation

Unit

MOID

Value

0.245141

1-sigma variation

Unit

Orbit Period

Value

1191.5480

1-sigma variation

Unit

U parameter

Value

0.0

1-sigma variation

Unit

Covariance Matrix

	a	e	i	Ω	ω	M
a	7.74824E-18	2.33343E-17	-4.27443E-16	-5.11892E-15	6.08102E-15	-7.04202E-15
e	2.33343E-17	5.19266E-16	-2.45041E-15	-1.07474E-14	2.83405E-15	5.55192E-16
i	-4.27443E-16	-2.45041E-15	8.07915E-12	1.50224E-11	-1.39021E-11	-7.02295E-13
Ω	-5.11892E-15	-1.07474E-14	1.50224E-11	8.42721E-10	-8.44899E-10	1.32175E-11
ω	6.08102E-15	2.83405E-15	-1.39021E-11	-8.44899E-10	8.82237E-10	-4.14892E-11
M	-7.04202E-15	5.55192E-16	-7.02295E-13	1.32175E-11	-4.14892E-11	3.13790E-11

Date of computation: 2026-07-15 14:31 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

8.400

Unit

Source

[2]

Quality

Value

Unit

Source

[2]

Amplitude

Value

0.25-0.5

Unit

mag

Source

[2]

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

[1]

Taxonomy (all)

Value

Unit

Source

[1]

Absolute Magnitude (H)
Slope Parameter (G)

H / G

Value

Unit

Source

Absolute Magnitude (H)

Value

17.26

17.053

Unit

mag

Source

[3]

[4]

Slope Parameter (G)

Value

0.235

0.15**

Unit

Source

[5]

[4]

Albedo
Diameter

Size and albedo

Value

Unit

Source

Albedo

Value

medium

Unit

Source

[6]

Diameter

Value

1200

Unit

Source

[6]

Color Index Information

Color Index Information

Value

Unit

Source

Color Index Information

Value

0.559

0.829

0.48

Unit

R-I

B-V

V-R

Source

[7]

Sightings

Sightings

Value

Unit

Source

Sightings

Value

Visual S

Unit

Source

[8]

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Sources

No.	Name	Additional
[1]	EARN	1.) Lazzarin, M., Marchi,S. & Magrin, S. (2010) href="http://www.astro.unipd.it/planets/sineo/data.html"> SINEO Database (Spectroscopic Investiation of Near-Earth Objects)
[2]	EARN	1.) Warner, B.D. (2016) MPB 43, 311-319. (NEAR-EARTH ASTEROID LIGHTCURVE ANALYSIS AT CS3-PALMER DIVIDE STATION: 2016 APRIL-JULY)(31 NEAs) 2.) Wisniewski, W.Z. et al. (1997) Icarus 126, 395-449. (Photometric Observations of 125 Asteroids) 3.) Hoffmann, M. (1991) M.P.B. 18, 10. (Photometry of 1990 KA) 4.) Petr Pravec's Ondrejov NEO Photometric Program Webpage "Prepublished Periods"
[3]	EARN	1.) Pravec, P. et al. (2012) Icarus 221, 365-387 (Absolute magnitudes of asteroids and a revision of asteroid albedo estimates from WISE thermal observations) 2.) Petr Pravec's Ondrejov NEO Photometric Program Webpage "Prepublished Periods" 3.) Wisniewski, W.Z. et al. (1997) Icarus 126, 395-449. (Photometric Observations of 125 Asteroids)
[4]	ESA Aegis	ESA orbit determination and impact monitoring system
[5]	EARN	1.) Pravec, P. et al. (2012) Icarus 221, 365-387 (Absolute magnitudes of asteroids and a revision of asteroid albedo estimates from WISE thermal observations)
[6]	EARN	1.) Binzel, R.P. et al. (2002) in "Asteroids III" (Eds. W.F.Bottke et al.), Univ.Ariz.Press, Tucson, USA, pp. 255-271. (Physical Properties of NEOs)
[7]	EARN	1.) Lin, C-H. et al. (2018) P&SS 152, 116-135. (Photometric survey and taxonomic identifications of 92 near-Earth asteroids)
[8]	EARN	1.) Lazzarin, M., Marchi,S. & Magrin, S. (2010) href="http://www.astro.unipd.it/planets/sineo/data.html"> SINEO Database (Spectroscopic Investiation of Near-Earth Objects) 2.) deLeon, J. et al. (2010) Astron. Astrophys 517, A23. (Observations, compositional, and physical characterization of near-Earth and Mars-crosser asteroids from a spectroscopic survey)

Observational Information

Arc Length
Unobserved
Normalized RMS of residuals

Arc Information

Value

Unit

Source

Arc Length

Value

27346

Unit

Source

[1]

Unobserved

Value

Unit

Source

[1]

Normalized RMS of residuals

Value

0.547019

Unit

Source

[1]

Astrometry Summary

First Observation
Last Observation
Total Optical Observations (Discarded)

Optical

Value

Unit

Source

First Observation

Value

1951-09-01.36111

Unit

Source

[2]

Last Observation

Value

2026-07-15.080156

Unit

Source

[2]

Total Optical Observations (Discarded)

Value

1044 (17)

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

Filters

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Final Date: *

Normalised Only accepted

Max residual (arcsec):

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Computation parameters

As seen from:

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Final Date: *

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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.

Stationary Points

Ecc. an. ast.	Ecc. an. Earth	Distance in au	Classification
4.18526748	154.86086603	0.24514090	MINIMUM
179.88885706	328.66566025	2.16786923	SADDLE
0.39609561	328.81486682	2.23357118	SADDLE
180.55824594	149.08811003	4.16261318	MAXIMUM

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MOID Plots

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