Asteroids

2025UN9 help

Last update: 2025-11-02 13:00 UTC

Orbital Properties

Epoch

61000.0

MJD

Orbit type

Apollo

Perihelion (q)

1.011

Aphelion (Q)

1.492

Eccentricity (e)

0.192

Inclination (i)

0.8

deg

Orbit period (P)

511.4

Earth MOID

0.01796

U parameter

6.7

Next Earth close approach

Date

2032-10-16

Nominal distance (from Earth center)

0.02431

3636563

Maximum Brightness

21.5

mag

Risk

Object is not in risk list

Physical Properties

Absolute Magnitude (H)

28.2

mag

Diameter

6 - 14*

Taxonomic type

Rotation period (T)

Discovery Information

Discovery Date

2025-10-29

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

1.251582

1-sigma variation

0.000144

Unit

Eccentricity (e)

Value

0.192193

1-sigma variation

0.000086

Unit

Inclination (i)

Value

0.7765

1-sigma variation

0.0003

Unit

Long. of Ascending Node (Ω)

Value

36.4668

1-sigma variation

0.0001

Unit

Arg. of Perihelion (ω)

Value

3.3557

1-sigma variation

0.0041

Unit

Mean Anomaly (M)

Value

13.05680

1-sigma variation

0.00190

Unit

Perihelion distance

Value

1.011037

1-sigma variation

Unit

Aphelion distance

Value

1.492128

1-sigma variation

Unit

Asc. Node-Earth Sep.

Value

0.018048

1-sigma variation

Unit

Desc. Node-Earth Sep.

Value

0.483541

1-sigma variation

Unit

MOID

Value

0.017956

1-sigma variation

Unit

Orbit Period

Value

511.4316

1-sigma variation

Unit

U parameter

Value

6.7

1-sigma variation

Unit

Covariance Matrix

	a	e	i	Ω	ω	M
a	2.06074E-8	1.23883E-8	4.68959E-8	4.73815E-9	-4.20852E-7	-5.02630E-8
e	1.23883E-8	7.44769E-9	2.81785E-8	2.83977E-9	-2.51213E-7	-3.13928E-8
i	4.68959E-8	2.81785E-8	1.07977E-7	1.04021E-8	-1.01518E-6	-7.60660E-8
Ω	4.73815E-9	2.83977E-9	1.04021E-8	3.00666E-9	-1.37376E-7	1.40858E-8
ω	-4.20852E-7	-2.51213E-7	-1.01518E-6	-1.37376E-7	1.66124E-5	-4.25941E-6
M	-5.02630E-8	-3.13928E-8	-7.60660E-8	1.40858E-8	-4.25941E-6	3.60825E-6

Date of computation: 2025-11-02 13:00 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

28.209

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

6 - 14*

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

0.517114

Unit

Source

[1]

Astrometry Summary

First Observation
Last Observation
Total Optical Observations (Discarded)

Optical

Value

Unit

Source

First Observation

Value

2025-10-29.200863

Unit

Source

[2]

Last Observation

Value

2025-11-01.152891

Unit

Source

[2]

Total Optical Observations (Discarded)

Value

35 (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 2025UN9 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	1979-09-25 09:40	> 1 d	0.0976530	0.0048073	0.0712893
EARTH	1986-10-15 17:15	> 1 w	0.0232776	0.0031560	0.0120150
EARTH	2018-12-03 08:17	418.4	0.1892541	0.1660535	0.0077339
EARTH	2025-10-31 16:36	2.0	0.0185490	0.0185247	0.0000081
EARTH	2032-10-16 16:59	> 1 d	0.0243089	0.0126651	0.0039261
EARTH	2057-11-18 23:51	> 1 w	0.0437478	0.0005860	0.0324642
EARTH	2064-10-03 03:08	> 1 w	0.0667866	0.0019502	0.0982790
EARTH	2096-10-31 09:36	> 1 mo	0.0174215	0.0160081	0.0160574
EARTH	2103-09-24 03:12	> 1 mo	0.1823846	0.0046668	5.2655362

Download as:

Stationary Points

Ecc. an. ast.	Ecc. an. Earth	Distance in au	Classification
355.55300961	294.00878728	0.01795617	MINIMUM
176.91012585	115.37157416	0.48354441	SADDLE
355.38249173	113.81564620	2.01941193	SADDLE
176.95457572	295.41731591	2.48501219	MAXIMUM

Download:

MOID Plots

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