Asteroids

2021GT3 help

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

Orbital Properties

Epoch

61000.0

MJD

Orbit type

Apollo

Perihelion (q)

0.411

Aphelion (Q)

2.542

Eccentricity (e)

0.722

Inclination (i)

4.1

deg

Orbit period (P)

655.2

Earth MOID

0.00142

U parameter

8.3

Next Earth close approach

Date

2026-12-01

Nominal distance (from Earth center)

0.05727

8567833

Maximum Brightness

23.5

mag

Risk

Object is not in risk list

Physical Properties

Absolute Magnitude (H)

26.3

mag

Diameter

15 - 30*

Taxonomic type

Rotation period (T)

Discovery Information

Discovery Date

2021-04-06

Observatory

Pan-STARRS 1, Haleakala

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

1.476334

1-sigma variation

0.001938

Unit

Eccentricity (e)

Value

0.721836

1-sigma variation

0.000548

Unit

Inclination (i)

Value

4.1155

1-sigma variation

0.0052

Unit

Long. of Ascending Node (Ω)

Value

19.7121

1-sigma variation

0.0003

Unit

Arg. of Perihelion (ω)

Value

295.2598

1-sigma variation

0.0017

Unit

Mean Anomaly (M)

Value

179.29560

1-sigma variation

1.75274

Unit

Perihelion distance

Value

0.410663

1-sigma variation

Unit

Aphelion distance

Value

2.542005

1-sigma variation

Unit

Asc. Node-Earth Sep.

Value

-0.457554

1-sigma variation

Unit

Desc. Node-Earth Sep.

Value

0.019115

1-sigma variation

Unit

MOID

Value

0.001418

1-sigma variation

Unit

Orbit Period

Value

655.2022

1-sigma variation

Unit

U parameter

Value

8.3

1-sigma variation

Unit

Covariance Matrix

	a	e	i	Ω	ω	M
a	3.75627E-6	1.06187E-6	1.00643E-5	5.95362E-7	3.31789E-6	-3.39701E-3
e	1.06187E-6	3.00182E-7	2.84513E-6	1.68302E-7	9.38009E-7	-9.60307E-4
i	1.00643E-5	2.84513E-6	2.69739E-5	1.59422E-6	8.89719E-6	-9.10173E-3
Ω	5.95362E-7	1.68302E-7	1.59422E-6	9.45982E-8	5.25172E-7	-5.38419E-4
ω	3.31789E-6	9.38009E-7	8.89719E-6	5.25172E-7	2.94336E-6	-3.00055E-3
M	-3.39701E-3	-9.60307E-4	-9.10173E-3	-5.38419E-4	-3.00055E-3	3.07211E0

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

26.281

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

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

1627

Unit

Source

[1]

Normalized RMS of residuals

Value

0.365257

Unit

Source

[1]

Astrometry Summary

First Observation
Last Observation
Total Optical Observations (Discarded)

Optical

Value

Unit

Source

First Observation

Value

2021-04-06.542373

Unit

Source

[2]

Last Observation

Value

2021-04-10.378655

Unit

Source

[2]

Total Optical Observations (Discarded)

Value

32 (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

Close Approaches for 2021GT3 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	1950-04-10 18:03	> 1 w	0.0049658	0.0005487	0.1707758
MERCURY	1955-09-16 14:50	> 1 mo	0.0147934	0.0043581	0.1410883
EARTH	1966-04-03 21:48	> 1 w	0.1516864	0.0007228	0.1807001
VENUS	1968-01-29 14:04	> 1 w	0.0465918	0.0446086	0.0603687
MERCURY	1975-04-04 18:45	> 1 w	0.0255061	0.0228431	0.1187797
EARTH	1978-12-04 16:42	> 1 w	0.1081156	0.0558776	0.2119178
MERCURY	1989-06-05 10:40	> 1 mo	0.0145238	0.0044912	0.1773331
EARTH	1994-11-27 15:55	> 1 w	0.0878062	0.0559704	0.1723879
MERCURY	2003-08-15 11:28	> 1 w	0.0355286	0.0040141	0.2228056
EARTH	2005-04-16 03:34	> 1 w	0.1228038	0.0006538	0.1773871
MARS	2012-03-25 04:31	> 1 d	0.0305772	0.0138868	0.0666763
EARTH	2021-04-10 21:33	< 1 min	0.0017091	0.0017044	0.0000016
MERCURY	2026-10-14 01:18	> 1 w	0.0270521	0.0255931	0.0115387
EARTH	2026-12-01 08:32	> 1 d	0.0572724	0.0528808	0.0248743
EARTH	2030-04-03 01:56	> 1 d	0.1827152	0.0011703	0.1112049
EARTH	2035-11-23 08:10	> 1 w	0.1722415	0.0540010	0.1720978
MERCURY	2042-12-10 02:19	> 1 w	0.0451315	0.0253274	0.3000398
MERCURY	2062-08-20 09:22	> 1 mo	0.0124408	0.0068229	0.2184200
EARTH	2073-04-15 13:50	> 1 d	0.0977045	0.0030545	0.0933949
MERCURY	2078-10-18 05:12	> 1 d	0.0269579	0.0220186	0.0021408
EARTH	2078-12-06 20:04	819.6	0.1472382	0.1018414	0.0157391
EARTH	2082-04-09 00:25	> 1 d	0.0601304	0.0033563	0.0830285
EARTH	2087-11-29 17:34	> 1 w	0.0624127	0.0541659	0.0840710
MERCURY	2094-12-18 18:07	> 1 w	0.0492269	0.0256014	0.3652671
MERCURY	2098-07-07 09:29	> 1 w	0.0370588	0.0057945	0.3694718
MERCURY	2114-09-03 20:57	> 1 mo	0.0195207	0.0047228	0.1765415

Download as:

Stationary Points

Ecc. an. ast.	Ecc. an. Earth	Distance in au	Classification
296.42613103	97.76960430	0.00147635	MINIMUM
62.36910523	325.99223443	0.05273261	MINIMUM
358.69415909	210.72091758	0.60426748	SADDLE
358.81731001	31.00452679	1.39650174	SADDLE
179.74428001	32.49312383	1.55902291	SADDLE
179.83848490	212.52543103	3.55395504	MAXIMUM

Download:

MOID Plots

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