Asteroids

2021LY1 help

Last update: 2024-04-24 13:40 UTC

Orbital Properties

Epoch

60400.0

MJD

Orbit type

Apollo

Perihelion (q)

0.722

Aphelion (Q)

1.409

Eccentricity (e)

0.322

Inclination (i)

12.9

deg

Orbit period (P)

401.6

Earth MOID

0.00010

U parameter

6.9

Next Earth close approach

Date

2032-06-02

Nominal distance (from Earth center)

0.03457

5172217

Maximum Brightness

23.7

mag

Risk

Object is in risk list

Object is not in priority list

Physical Properties

Absolute Magnitude (H)

mag

Diameter

7 - 15*

Taxonomic type

Rotation period (T)

Discovery Information

Discovery Date

2021-06-06

Observatory

Mt. Lemmon Survey

Orbit Visualiser

Click the button to start Orbit Visualiser

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

60400.0000

1-sigma variation

Unit

MJD

Semimajor Axis

Value

1.065316

1-sigma variation

0.000124

Unit

Eccentricity (e)

Value

0.322164

1-sigma variation

0.000160

Unit

Inclination (i)

Value

12.8831

1-sigma variation

0.0069

Unit

Long. of Ascending Node (Ω)

Value

253.3504

1-sigma variation

0.0001

Unit

Arg. of Perihelion (ω)

Value

259.5046

1-sigma variation

0.0056

Unit

Mean Anomaly (M)

Value

267.14546

1-sigma variation

0.18572

Unit

Perihelion distance

Value

0.722110

1-sigma variation

Unit

Aphelion distance

Value

1.408523

1-sigma variation

Unit

Asc. Node-Earth Sep.

Value

-0.000168

1-sigma variation

Unit

Desc. Node-Earth Sep.

Value

-0.082910

1-sigma variation

Unit

MOID

Value

0.000095

1-sigma variation

Unit

Orbit Period

Value

401.6210

1-sigma variation

Unit

U parameter

Value

6.9

1-sigma variation

Unit

Covariance Matrix

	a	e	i	Ω	ω	M
a	1.53592E-8	1.97881E-8	8.53281E-7	-5.23914E-9	6.95617E-7	-2.30170E-5
e	1.97881E-8	2.55084E-8	1.09999E-6	-6.48783E-9	8.94929E-7	-2.96548E-5
i	8.53281E-7	1.09999E-6	4.74347E-5	-2.78878E-7	3.85865E-5	-1.27874E-3
Ω	-5.23914E-9	-6.48783E-9	-2.78878E-7	6.88212E-9	-2.60753E-7	7.83859E-6
ω	6.95617E-7	8.94929E-7	3.85865E-5	-2.60753E-7	3.16185E-5	-1.04238E-3
M	-2.30170E-5	-2.96548E-5	-1.27874E-3	7.83859E-6	-1.04238E-3	3.44929E-2

Date of computation: 2024-04-23 10:08 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

28.047

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

7 - 15*

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 ODIM	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

1047

Unit

Source

[1]

Normalized RMS of residuals

Value

0.700218

Unit

Source

[1]

Astrometry Summary

First Observation
Last Observation
Total Optical Observations (Discarded)

Optical

Value

Unit

Source

First Observation

Value

2021-06-06.27678

Unit

Source

[2]

Last Observation

Value

2021-06-12.33953

Unit

Source

[2]

Total Optical Observations (Discarded)

Value

32 (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

[3]

Last Observation

Value

Unit

Source

[3]

Delay (Discarded)

Value

0 (0)

Unit

Source

[1]

Doppler (Discarded)

Value

0 (0)

Unit

Source

[1]

Total Radar Observations (Discarded)

Value

0 (0)

Unit

Source

[1]

Note: The ASCII file is in a format suitable for Orbfit input.

Sources

No.	Name	Additional
[1]	ESA ODIM	ESA orbit determination and impact monitoring system
[2]	MPC	Minor Planet Center: https://www.minorplanetcenter.net
[3]	JPL Radar Observations	Jet Propulsion Laboratory: https://ssd.jpl.nasa.gov/dat/radar_data_ast.txt

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 2021LY1 from 1950 to 2124

Body	Date in UTC	Time uncert. in min	Nominal distance in au	Min. possibile distance in au	Distance uncert. in au
EARTH	1950-11-18 21:11	> 1 w	0.0859924	0.0654365	0.0921093
EARTH	1953-05-30 21:18	> 1 d	0.1203515	0.0004165	0.1326820
EARTH	1967-06-10 20:36	> 1 d	0.1527279	0.0012085	0.0599825
EARTH	1977-11-24 00:29	> 1 d	0.0674671	0.0653570	0.0044311
EARTH	1980-06-02 08:55	> 1 d	0.0353816	0.0006738	0.0387550
EARTH	1994-06-09 18:54	> 1 d	0.1311920	0.0525169	0.0262267
EARTH	2004-11-15 10:31	1351.5	0.1249837	0.0848524	0.0150143
EARTH	2007-05-31 10:09	540.7	0.1868402	0.1398280	0.0156715
EARTH	2018-11-28 19:07	303.3	0.0984883	0.0933715	0.0017461
EARTH	2021-06-04 04:32	< 1 min	0.0027128	0.0027086	0.0000014
EARTH	2032-06-02 10:27	663.8	0.0345741	0.0005185	0.0114039
EARTH	2043-05-30 00:29	144.4	0.1572220	0.1311485	0.0086914
EARTH	2052-12-06 05:31	> 1 d	0.1379281	0.0799987	0.0220634
EARTH	2063-11-26 03:48	> 1 d	0.0523584	0.0515601	0.0066569
EARTH	2066-06-13 00:01	> 1 d	0.1971193	0.0470852	0.0500690
EARTH	2074-11-19 10:58	> 1 d	0.1112256	0.0531665	0.0827476
EARTH	2077-06-08 01:20	> 1 d	0.0888159	0.0018837	0.0977408
EARTH	2088-06-03 19:60	> 1 d	0.0044579	0.0012151	0.0844793
EARTH	2110-11-26 02:59	> 1 mo	0.0605316	0.0579925	6.5012497
EARTH	2113-06-07 14:20	> 1 mo	0.0554976	0.0019848	27.8050990
EARTH	2122-11-15 13:17	> 1 mo	0.1718732	0.0630662	21.5414791

Download as:

2021LY1

Date in UTC	MJD	σ	σ_imp	Distance ± Width in RE	Stretching in RE/σ	IP	Exp. energy	PS	TS
2040-06-03.777	66308.777	2.625	0.000	1.12 ± 0.003	4.08E5	5.21E-8	1.05E-9	-8.33	0


Based on 32 optical observations (of which 0 are rejected as outliers) from 2021/06/06.277 to 2021/06/12.340.
Coordinates are given on the Target Plane.
Unit is one Earth radius, but impact cross section has radius between 1.40 and 1.40 Earth radii.
Coordinates for LOV = EQU scaled= 1 second= F.
AstOD software version= 4.0, Date of computation=20240110 090429.849 UTC.

Download this part as:

Download Impactor Table as: