Asteroids

1998SH2 help

Last update: 2025-07-29 02:36 UTC

Orbital Properties

Epoch

60800.0

MJD

Orbit type

Apollo

Perihelion (q)

0.785

Aphelion (Q)

4.702

Eccentricity (e)

0.714

Inclination (i)

2.4

deg

Orbit period (P)

1659.6

Earth MOID

0.01892

U parameter

0.2

Next Earth close approach

Date

2025-08-30

Nominal distance (from Earth center)

0.02078

3108357

Maximum Brightness

14.8

mag

Risk

Object is not in risk list

Physical Properties

Absolute Magnitude (H)

20.8

mag

Diameter

300

Taxonomic type

Rotation period (T)

Discovery Information

Discovery Date

1998-09-17

Observatory

Steward Observatory, Kitt Peak-Spacewatch

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

60800.0000

1-sigma variation

Unit

MJD

Semimajor Axis

Value

2.743233

1-sigma variation

3.548E-8

Unit

Eccentricity (e)

Value

0.713887

1-sigma variation

6.657E-8

Unit

Inclination (i)

Value

2.4043

1-sigma variation

2.069E-5

Unit

Long. of Ascending Node (Ω)

Value

6.3683

1-sigma variation

0.0001

Unit

Arg. of Perihelion (ω)

Value

268.4296

1-sigma variation

0.0001

Unit

Mean Anomaly (M)

Value

343.21200

1-sigma variation

0.00002

Unit

Perihelion distance

Value

0.784874

1-sigma variation

Unit

Aphelion distance

Value

4.701591

1-sigma variation

Unit

Asc. Node-Earth Sep.

Value

0.370815

1-sigma variation

Unit

Desc. Node-Earth Sep.

Value

0.321183

1-sigma variation

Unit

MOID

Value

0.018920

1-sigma variation

Unit

Orbit Period

Value

1659.5579

1-sigma variation

Unit

U parameter

Value

0.2

1-sigma variation

Unit

Covariance Matrix

	a	e	i	Ω	ω	M
a	1.25873E-15	1.19035E-15	-3.41979E-13	5.47550E-13	1.86614E-13	-7.60409E-13
e	1.19035E-15	4.43093E-15	-1.37863E-13	-6.04187E-13	1.68974E-12	-5.38693E-13
i	-3.41979E-13	-1.37863E-13	4.28046E-10	-1.42128E-9	1.43826E-9	1.12837E-10
Ω	5.47550E-13	-6.04187E-13	-1.42128E-9	1.23278E-8	-1.29094E-8	2.46315E-11
ω	1.86614E-13	1.68974E-12	1.43826E-9	-1.29094E-8	1.40902E-8	-5.11574E-10
M	-7.60409E-13	-5.38693E-13	1.12837E-10	2.46315E-11	-5.11574E-10	5.09563E-10

Date of computation: 2025-07-29 02:36 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

20.789

Unit

mag

Source

[1]

Slope Parameter (G)

Value

0.15**

Unit

mag

Source

[1]

Albedo
Diameter

Size and albedo

Value

Unit

Source

Albedo

Value

0.0578

Unit

Source

[2]

Diameter

Value

300

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]	EARN	1.) Masiero, J.R. et al. (2018) Astron. J. 154_168(10pp). (NEOWISE Reactivation Mission Year Three: Asteroid Diameters and Albedos) (170NEOs, 6110MBAs)

Observational Information

Arc Length
Unobserved
Normalized RMS of residuals

Arc Information

Value

Unit

Source

Arc Length

Value

6615

Unit

Source

[1]

Unobserved

Value

3225

Unit

Source

[1]

Normalized RMS of residuals

Value

0.762695

Unit

Source

[1]

Astrometry Summary

First Observation
Last Observation
Total Optical Observations (Discarded)

Optical

Value

Unit

Source

First Observation

Value

1998-09-17.4442

Unit

Source

[2]

Last Observation

Value

2016-10-27.25869

Unit

Source

[2]

Total Optical Observations (Discarded)

Value

152 (2)

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 1998SH2 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	1958-09-07 10:26	< 1 min	0.0389476	0.0389466	0.0000003
EARTH	1967-04-06 22:41	< 1 min	0.0726539	0.0726344	0.0000065
JUPITER	1977-11-22 04:17	< 1 min	0.6929472	0.6929462	0.0000003
EARTH	1989-09-04 11:17	< 1 min	0.0310272	0.0310249	0.0000008
EARTH	1998-08-25 14:03	< 1 min	0.0883026	0.0883014	0.0000004
EARTH	2025-08-30 13:23	< 1 min	0.0207781	0.0207774	0.0000002
EARTH	2052-09-08 22:12	2.9	0.0697869	0.0697017	0.0000284
EARTH	2061-09-03 17:23	< 1 min	0.0164732	0.0164683	0.0000016
JUPITER	2073-02-02 22:59	< 1 min	0.6514698	0.6514476	0.0000074
EARTH	2079-04-04 20:37	4.5	0.1504963	0.1503300	0.0000554
VENUS	2088-03-07 07:16	14.4	0.0355864	0.0354013	0.0000617
EARTH	2092-09-05 21:18	3.9	0.0538873	0.0537971	0.0000301
EARTH	2101-04-05 21:08	14.9	0.1742729	0.1737009	0.0001907

Download as:

Stationary Points

Ecc. an. ast.	Ecc. an. Earth	Distance in au	Classification
332.45947996	109.75338875	0.01891953	MINIMUM
27.77640411	235.71474765	0.02076393	MINIMUM
0.15922346	172.80065158	0.23432429	SADDLE
0.14609030	352.77276385	1.76826278	SADDLE
180.02545590	352.59829347	3.71891236	SADDLE
180.02508497	172.59897081	5.71702269	MAXIMUM

Download:

MOID Plots

Click on the images to zoom-in and zoom-out