Asteroids

2025YS9 help

Last update: 2026-01-03 13:01 UTC

Orbital Properties

Epoch

61000.0

MJD

Orbit type

Aten

Perihelion (q)

0.684

Aphelion (Q)

1.252

Eccentricity (e)

0.293

Inclination (i)

14.0

deg

Orbit period (P)

347.9

Earth MOID

0.01796

U parameter

6.7

Next Earth close approach

Date

2042-08-03

Nominal distance (from Earth center)

0.15856

23719885

Maximum Brightness

27.1

mag

Risk

Object is not in risk list

Physical Properties

Absolute Magnitude (H)

26.2

mag

Diameter

15 - 30*

Taxonomic type

Rotation period (T)

Discovery Information

Discovery Date

2025-12-31

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

0.968055

1-sigma variation

0.000078

Unit

Eccentricity (e)

Value

0.293387

1-sigma variation

0.000207

Unit

Inclination (i)

Value

13.9753

1-sigma variation

0.0117

Unit

Long. of Ascending Node (Ω)

Value

98.5771

1-sigma variation

3.172E-5

Unit

Arg. of Perihelion (ω)

Value

115.5031

1-sigma variation

0.0052

Unit

Mean Anomaly (M)

Value

236.77726

1-sigma variation

0.03600

Unit

Perihelion distance

Value

0.684040

1-sigma variation

Unit

Aphelion distance

Value

1.252070

1-sigma variation

Unit

Asc. Node-Earth Sep.

Value

0.029151

1-sigma variation

Unit

Desc. Node-Earth Sep.

Value

-0.232679

1-sigma variation

Unit

MOID

Value

0.017959

1-sigma variation

Unit

Orbit Period

Value

347.8952

1-sigma variation

Unit

U parameter

Value

6.7

1-sigma variation

Unit

Covariance Matrix

	a	e	i	Ω	ω	M
a	6.11181E-9	1.61507E-8	9.13879E-7	-2.40950E-9	-4.07790E-7	2.81435E-6
e	1.61507E-8	4.27356E-8	2.41968E-6	-6.39513E-9	-1.07437E-6	7.44026E-6
i	9.13879E-7	2.41968E-6	1.37128E-4	-3.63189E-7	-6.06820E-5	4.21061E-4
Ω	-2.40950E-9	-6.39513E-9	-3.63189E-7	1.00613E-9	1.58863E-7	-1.11079E-6
ω	-4.07790E-7	-1.07437E-6	-6.06820E-5	1.58863E-7	2.74000E-5	-1.87603E-4
M	2.81435E-6	7.44026E-6	4.21061E-4	-1.11079E-6	-1.87603E-4	1.29614E-3

Date of computation: 2026-01-03 13:01 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

26.24

Unit

mag

Source

[1]

Slope Parameter (G)

Value

0.15**

Unit

Source

[1]

Albedo
Diameter

Size and albedo

Value

Unit

Source

Albedo

Value

0.05 - 0.25

Unit

Source

[2]

Diameter

Value

15 - 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

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

Unit

Source

[1]

Normalized RMS of residuals

Value

0.630041

Unit

Source

[1]

Astrometry Summary

First Observation
Last Observation
Total Optical Observations (Discarded)

Optical

Value

Unit

Source

First Observation

Value

2025-12-29.25625

Unit

Source

[2]

Last Observation

Value

2026-01-01.15888

Unit

Source

[2]

Total Optical Observations (Discarded)

Value

33 (3)

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 2025YS9 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	1960-08-09 06:21	1055.2	0.1713867	0.1630885	0.0036937
EARTH	1964-12-31 22:47	1427.0	0.0677890	0.0180735	0.0351233
EARTH	1981-07-30 10:11	> 1 w	0.1596243	0.1578519	0.0118159
EARTH	1985-01-01 22:09	> 1 d	0.0986342	0.0211189	0.0783858
EARTH	1985-12-28 11:39	> 1 d	0.1863565	0.0179570	0.0803906
EARTH	2002-07-16 00:04	> 1 d	0.1948862	0.1736486	0.0122928
EARTH	2006-01-02 11:09	269.1	0.0199346	0.0176503	0.0052805
EARTH	2022-07-22 05:21	834.5	0.1793271	0.1755744	0.0013276
EARTH	2026-01-02 18:02	< 1 min	0.0197997	0.0197539	0.0000153
EARTH	2042-08-03 14:42	> 1 d	0.1585576	0.1585106	0.0002734
EARTH	2046-01-01 07:31	> 1 d	0.1182334	0.0574901	0.0207674
EARTH	2046-12-29 13:10	1011.5	0.1690951	0.1012891	0.0227054
EARTH	2062-08-13 06:06	> 1 d	0.1893358	0.1622407	0.0154643
EARTH	2067-01-01 17:38	1080.4	0.0666495	0.0193233	0.0291682
EARTH	2083-07-15 14:40	> 1 d	0.1997507	0.1840563	0.0060843
VENUS	2084-06-06 23:13	1129.7	0.0486348	0.0485495	0.0009356
EARTH	2087-01-02 09:40	809.4	0.0425779	0.0196154	0.0227098
EARTH	2102-08-14 20:44	> 1 d	0.1916366	0.1651009	0.0186615
EARTH	2105-12-25 16:15	> 1 d	0.1914274	0.1035041	0.0306739
EARTH	2107-01-02 02:18	1427.9	0.0962262	0.0202684	0.0360221
EARTH	2122-08-07 00:43	> 1 d	0.1621236	0.1612843	0.0010243
EARTH	2126-01-03 05:37	206.1	0.0977991	0.0866150	0.0037446

Download as:

Stationary Points

Ecc. an. ast.	Ecc. an. Earth	Distance in au	Classification
264.64426298	0.55316936	0.01795864	MINIMUM
80.25380359	210.04630887	0.15951442	MINIMUM
170.08185821	286.73298243	0.36026634	SADDLE
354.26435867	104.08048357	0.37299984	SADDLE
1.61294883	294.33212013	1.66817338	SADDLE
184.46548735	117.53787706	2.24717213	MAXIMUM

Download:

MOID Plots

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