Asteroids

2026HH4 help

Last update: 2026-04-27 12:45 UTC

Orbital Properties

Epoch

61200.0

MJD

Orbit type

Aten

Perihelion (q)

0.414

Aphelion (Q)

1.345

Eccentricity (e)

0.529

Inclination (i)

0.3

deg

Orbit period (P)

301.4

Earth MOID

0.00253

U parameter

6.6

Next Earth close approach

Date

2027-07-18

Nominal distance (from Earth center)

0.19942

29832392

Maximum Brightness

25.6

mag

Risk

Object is in risk list

Physical Properties

Absolute Magnitude (H)

27.3

mag

Diameter

9 - 21*

Taxonomic type

Rotation period (T)

Discovery Information

Discovery Date

2026-04-24

Observatory

GINOP-KHK, Piszkesteto

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

0.879795

1-sigma variation

0.000052

Unit

Eccentricity (e)

Value

0.528891

1-sigma variation

0.000241

Unit

Inclination (i)

Value

0.3341

1-sigma variation

0.0004

Unit

Long. of Ascending Node (Ω)

Value

148.9800

1-sigma variation

0.1056

Unit

Arg. of Perihelion (ω)

Value

289.8383

1-sigma variation

0.1063

Unit

Mean Anomaly (M)

Value

131.76373

1-sigma variation

0.03513

Unit

Perihelion distance

Value

0.414480

1-sigma variation

Unit

Aphelion distance

Value

1.345110

1-sigma variation

Unit

Asc. Node-Earth Sep.

Value

-0.450676

1-sigma variation

Unit

Desc. Node-Earth Sep.

Value

-0.240074

1-sigma variation

Unit

MOID

Value

0.002529

1-sigma variation

Unit

Orbit Period

Value

301.4188

1-sigma variation

Unit

U parameter

Value

6.6

1-sigma variation

Unit

Covariance Matrix

	a	e	i	Ω	ω	M
a	2.66070E-9	1.23906E-8	1.17385E-8	8.63501E-7	-9.99146E-7	-1.81083E-6
e	1.23906E-8	5.78605E-8	5.72908E-8	5.02154E-6	-5.65796E-6	-8.44791E-6
i	1.17385E-8	5.72908E-8	1.24187E-7	3.18537E-5	-3.25228E-5	-8.24751E-6
Ω	8.63501E-7	5.02154E-6	3.18537E-5	1.11487E-2	-1.12195E-2	-6.86314E-4
ω	-9.99146E-7	-5.65796E-6	-3.25228E-5	-1.12195E-2	1.12974E-2	7.79078E-4
M	-1.81083E-6	-8.44791E-6	-8.24751E-6	-6.86314E-4	7.79078E-4	1.23385E-3

Date of computation: 2026-04-27 12:45 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

27.27

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

9 - 21*

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

[-]

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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

0.729284

Unit

Source

[1]

Astrometry Summary

First Observation
Last Observation
Total Optical Observations (Discarded)

Optical

Value

Unit

Source

First Observation

Value

2026-04-24.842492

Unit

Source

[2]

Last Observation

Value

2026-04-25.917633

Unit

Source

[2]

Total Optical Observations (Discarded)

Value

52 (1)

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

Note: Ephemerides requests are limited to a maximum of 1000 points and a final date not exceeding 2040/12/31 00:00.

Close Approaches for 2026HH4 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
VENUS	1952-01-06 05:51	> 1 w	0.0423583	0.0423146	0.0118593
EARTH	1952-07-25 14:03	1386.9	0.0061575	0.0059735	0.0145578
EARTH	1960-04-27 12:08	590.6	0.1692980	0.1487354	0.0068550
VENUS	1960-11-21 01:31	180.1	0.0441505	0.0418432	0.0016139
EARTH	1965-04-25 14:30	> 1 d	0.1388220	0.0521226	0.0289274
EARTH	1966-07-26 10:48	600.8	0.0678116	0.0017940	0.0401730
EARTH	1979-04-23 04:01	197.3	0.0368649	0.0045239	0.1117623
EARTH	1980-07-21 04:12	> 1 w	0.1632269	0.0012974	0.0849995
EARTH	1985-07-22 04:57	> 1 d	0.1406287	0.0109873	0.0606550
VENUS	1993-03-25 12:04	1100.5	0.0460952	0.0393433	0.0096616
EARTH	1993-04-23 04:18	466.5	0.0091926	0.0045098	0.0118220
EARTH	1999-07-26 15:30	232.8	0.0160645	0.0053294	0.0077201
VENUS	1999-08-24 23:14	632.4	0.0444044	0.0435185	0.0020794
EARTH	2007-04-28 18:59	407.3	0.1725324	0.1479336	0.0082003
EARTH	2012-04-24 13:14	455.0	0.1197156	0.1012999	0.0061396
EARTH	2013-07-26 06:46	187.0	0.0907946	0.0757433	0.0050189
EARTH	2018-07-20 21:18	165.8	0.1972116	0.1881650	0.0030156
EARTH	2026-04-23 16:54	< 1 min	0.0052510	0.0052422	0.0000029
EARTH	2027-07-18 08:45	232.1	0.1994172	0.1959622	0.0011517
VENUS	2029-07-12 22:49	138.9	0.0391599	0.0388605	0.0002621
EARTH	2032-07-25 04:38	161.2	0.0574660	0.0441527	0.0044392
EARTH	2040-04-27 03:48	294.3	0.1416231	0.1243209	0.0057680
EARTH	2045-04-26 05:51	587.7	0.1397964	0.1232973	0.0055003
EARTH	2046-07-27 03:23	141.9	0.0719178	0.0513312	0.0068641
EARTH	2059-04-24 10:11	123.8	0.0190467	0.0092789	0.0034327
VENUS	2063-05-14 06:25	215.2	0.0386732	0.0386545	0.0000851
EARTH	2065-07-27 03:51	198.4	0.0114593	0.0027310	0.0069197
EARTH	2070-07-22 15:20	974.2	0.1643350	0.1009453	0.0211322
EARTH	2083-04-24 21:08	> 1 d	0.0485107	0.0057327	0.0849198
VENUS	2084-11-23 03:36	> 1 d	0.0399795	0.0385006	0.0274632
EARTH	2088-04-24 00:30	> 1 d	0.1091405	0.0066382	0.0897181
EARTH	2089-07-25 08:11	> 1 d	0.1315998	0.0016034	0.0909921
EARTH	2094-07-26 22:38	> 1 d	0.0285461	0.0028585	0.1081821
EARTH	2107-04-28 10:46	> 1 d	0.1252849	0.0067974	0.1798147
EARTH	2112-04-24 10:31	> 1 d	0.0774472	0.0059958	0.2612002
EARTH	2113-07-24 21:19	> 1 w	0.1520919	0.0028844	0.2390087
EARTH	2118-07-27 18:42	> 1 d	0.0390292	0.0027957	0.3022934

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Stationary Points

Ecc. an. ast.	Ecc. an. Earth	Distance in au	Classification
252.99524615	199.38606828	0.00252857	MINIMUM
105.64099705	107.84096488	0.00521646	MINIMUM
179.48667864	153.81389884	0.33002270	SADDLE
358.31228944	332.42767020	0.57077043	SADDLE
358.25905969	152.36554435	1.42953076	SADDLE
179.50538966	333.83387836	2.33025347	MAXIMUM

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MOID Plots

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

Level lines of the squared distance function

2026HH4

Date in UTC	MJD	σ	σ_imp	Distance ± Width in RE	Stretching in RE	IP	Impact energy	PS	TS
2090-07-27.280	84624.280	-1.600	0.000	0.94 ± 0.404	1.50E7	1.03E-8	1.10E-1	-9.05	0
2105-07-28.864	90103.864	-2.056	0.000	0.50 ± 0.383	1.09E6	9.32E-8	1.10E-1	-8.18	0
2107-07-28.594	90833.594	-1.505	0.000	0.79 ± 0.100	1.16E8	2.20E-9	1.10E-1	-9.82	0
2117-07-28.539	94486.539	-0.892	0.000	0.40 ± 2.230	8.72E6	2.58E-8	1.10E-1	-8.80	0
2118-07-28.542	94851.542	-1.690	0.000	0.39 ± 0.181	2.43E4	9.29E-6	1.10E-1	-6.25	0
2118-07-28.574	94851.574	-1.062	0.099	1.25 ± 0.342	7.97E3	1.83E-5	1.15E-1	-5.93	0
2119-07-28.824	95216.824	-1.061	0.000	0.96 ± 0.270	5.08E7	6.24E-9	1.10E-1	-9.42	0
2123-07-28.771	96677.771	-1.685	0.000	0.78 ± 0.179	8.47E5	2.68E-7	1.10E-1	-7.81	0
2123-07-28.823	96677.823	-1.048	0.000	1.13 ± 0.336	3.02E5	7.29E-7	1.10E-1	-7.37	0
2124-07-28.083	97043.083	-1.059	0.000	1.00 ± 0.331	1.11E7	4.83E-8	1.10E-1	-8.56	0
2126-07-28.273	97773.273	-1.325	0.000	0.19 ± 0.545	7.73E5	4.71E-7	1.10E-1	-7.58	n/a
2126-07-28.273	97773.273	-1.325	0.000	0.09 ± 0.591	7.71E5	4.60E-7	1.10E-1	-7.59	n/a
2126-07-28.640	97773.640	-1.062	0.000	1.02 ± 0.000	1.77E8	2.43E-9	1.10E-1	-9.86	n/a


Based on 52 optical observations (of which 1 are rejected as outliers) from 2026/04/24.842 to 2026/04/25.918.
Coordinates are given on the Target Plane.
Unit is one Earth radius, but impact cross section has radius between 1.25 and 1.25 Earth radii.
Coordinates for LOV = EQU scaled= 1 second= F.
Aegis software version= 5.0, Date of computation=20260427 133650.694 UTC.

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