Asteroids

2018AS2 help

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

Orbital Properties

Epoch

61000.0

MJD

Orbit type

Aten

Perihelion (q)

0.752

Aphelion (Q)

1.191

Eccentricity (e)

0.226

Inclination (i)

5.4

deg

Orbit period (P)

349.7

Earth MOID

0.00153

U parameter

6.5

Next Earth close approach

Date

2036-08-29

Nominal distance (from Earth center)

0.1769

26463368

Maximum Brightness

28.1

mag

Risk

Object is not in risk list

Physical Properties

Absolute Magnitude (H)

28.6

mag

Diameter

5 - 11*

Taxonomic type

Rotation period (T)

Discovery Information

Discovery Date

2018-01-12

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

0.971412

1-sigma variation

0.000049

Unit

Eccentricity (e)

Value

0.225725

1-sigma variation

0.000125

Unit

Inclination (i)

Value

5.4321

1-sigma variation

0.0038

Unit

Long. of Ascending Node (Ω)

Value

293.0574

1-sigma variation

0.0013

Unit

Arg. of Perihelion (ω)

Value

287.2662

1-sigma variation

0.0083

Unit

Mean Anomaly (M)

Value

351.98470

1-sigma variation

0.18802

Unit

Perihelion distance

Value

0.752140

1-sigma variation

Unit

Aphelion distance

Value

1.190683

1-sigma variation

Unit

Asc. Node-Earth Sep.

Value

-0.153670

1-sigma variation

Unit

Desc. Node-Earth Sep.

Value

0.004109

1-sigma variation

Unit

MOID

Value

0.001534

1-sigma variation

Unit

Orbit Period

Value

349.7063

1-sigma variation

Unit

U parameter

Value

6.5

1-sigma variation

Unit

Covariance Matrix

	a	e	i	Ω	ω	M
a	2.35446E-9	5.94999E-9	1.82131E-7	6.39363E-8	-4.00371E-7	-9.12258E-6
e	5.94999E-9	1.56606E-8	4.74519E-7	1.62409E-7	-9.85263E-7	-2.30079E-5
i	1.82131E-7	4.74519E-7	1.44155E-5	4.96487E-6	-3.03653E-5	-7.04635E-4
Ω	6.39363E-8	1.62409E-7	4.96487E-6	1.73735E-6	-1.08368E-5	-2.47666E-4
ω	-4.00371E-7	-9.85263E-7	-3.03653E-5	-1.08368E-5	6.92093E-5	1.55323E-3
M	-9.12258E-6	-2.30079E-5	-7.04635E-4	-2.47666E-4	1.55323E-3	3.53497E-2

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

28.589

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

5 - 11*

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

2844

Unit

Source

[1]

Normalized RMS of residuals

Value

0.90416

Unit

Source

[1]

Astrometry Summary

First Observation
Last Observation
Total Optical Observations (Discarded)

Optical

Value

Unit

Source

First Observation

Value

2018-01-12.33089

Unit

Source

[2]

Last Observation

Value

2018-01-13.55917

Unit

Source

[2]

Total Optical Observations (Discarded)

Value

16 (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

[-]

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 2018AS2 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	1959-08-27 21:23	> 1 mo	0.0785332	0.0779850	1.1987859
EARTH	1960-12-05 22:55	> 1 mo	0.1791680	0.0912938	4.1108565
EARTH	1972-09-06 07:55	> 1 mo	0.1993286	0.0685854	2.0485258
EARTH	1975-01-14 17:57	209.9	0.0010626	0.0006297	0.0081668
EARTH	1976-01-10 07:51	518.3	0.1417648	0.1096207	0.0107147
EARTH	2010-08-21 21:13	166.0	0.1372139	0.1296682	0.0025284
EARTH	2011-08-15 00:56	196.4	0.0519832	0.0510602	0.0004487
EARTH	2012-07-19 02:48	1213.0	0.1504749	0.1459270	0.0015251
EARTH	2017-01-01 17:21	172.6	0.1323313	0.1316418	0.0002299
EARTH	2018-01-14 11:17	< 1 min	0.0029836	0.0029778	0.0000019
EARTH	2036-08-29 12:20	430.6	0.1768967	0.1532485	0.0079627
EARTH	2037-08-15 07:28	1148.7	0.1053761	0.0851379	0.0071961
EARTH	2039-12-22 08:52	> 1 d	0.1541983	0.1357133	0.0061971
EARTH	2040-02-14 21:44	> 1 d	0.1767512	0.1527663	0.0080418
EARTH	2041-01-12 00:17	407.0	0.0903329	0.0610948	0.0097471
EARTH	2059-08-27 14:46	307.3	0.1212854	0.1071555	0.0048165
EARTH	2060-07-24 17:27	> 1 d	0.1571729	0.1438989	0.0045220
EARTH	2060-09-08 04:22	> 1 d	0.1616874	0.1481245	0.0045311
EARTH	2063-01-08 19:17	> 1 d	0.1036663	0.0842687	0.0064744
EARTH	2064-01-10 14:04	351.7	0.1541042	0.1319868	0.0073726
EARTH	2082-08-24 05:58	433.9	0.0714946	0.0628763	0.0035278
EARTH	2083-07-05 01:08	> 1 d	0.1972095	0.1881159	0.0030844
EARTH	2083-10-03 14:05	> 1 d	0.1965544	0.1894805	0.0023616
EARTH	2086-01-14 20:19	25.8	0.0298657	0.0140365	0.0053019
EARTH	2106-08-19 22:49	> 1 d	0.0737052	0.0585562	0.0233344
EARTH	2108-12-07 16:05	> 1 w	0.1868902	0.1327343	0.0187906
EARTH	2110-01-15 06:33	1394.1	0.0208648	0.0031851	0.0468555

Download as:

Stationary Points

Ecc. an. ast.	Ecc. an. Earth	Distance in au	Classification
266.55306392	11.50863898	0.00140548	MINIMUM
95.43357845	226.93268003	0.05825445	MINIMUM
179.78112887	298.66804874	0.22152546	SADDLE
2.02273615	119.61479680	0.26738771	SADDLE
4.07508113	302.25291758	1.74204629	SADDLE
183.25748254	121.43372622	2.19631843	MAXIMUM

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MOID Plots

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