Asteroids

2021PH27 help

Last update: 2025-05-15 00:00 UTC

Orbital Properties

Epoch

60800.0

MJD

Orbit type

Atira

Perihelion (q)

0.133

Aphelion (Q)

0.790

Eccentricity (e)

0.712

Inclination (i)

31.9

deg

Orbit period (P)

114.6

Earth MOID

0.22543

U parameter

2.5

Next Earth close approach

Date

Nominal distance (from Earth center)

Maximum Brightness

mag

Risk

Object is not in risk list

Object is not in priority list

Physical Properties

Absolute Magnitude (H)

17.6

mag

Diameter

800 - 1800*

Taxonomic type

Rotation period (T)

Discovery Information

Discovery Date

2021-08-13

Observatory

Cerro Tololo Observatory, La Serena

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

60800.0000

1-sigma variation

Unit

MJD

Semimajor Axis

Value

0.461757

1-sigma variation

1.876E-8

Unit

Eccentricity (e)

Value

0.711564

1-sigma variation

0.000001

Unit

Inclination (i)

Value

31.9414

1-sigma variation

0.0001

Unit

Long. of Ascending Node (Ω)

Value

39.3966

1-sigma variation

0.0001

Unit

Arg. of Perihelion (ω)

Value

8.5796

1-sigma variation

3.072E-5

Unit

Mean Anomaly (M)

Value

140.25670

1-sigma variation

0.00020

Unit

Perihelion distance

Value

0.133187

1-sigma variation

Unit

Aphelion distance

Value

0.790326

1-sigma variation

Unit

Asc. Node-Earth Sep.

Value

-0.858494

1-sigma variation

Unit

Desc. Node-Earth Sep.

Value

-0.238143

1-sigma variation

Unit

MOID

Value

0.225429

1-sigma variation

Unit

Orbit Period

Value

114.6089

1-sigma variation

Unit

U parameter

Value

2.5

1-sigma variation

Unit

Covariance Matrix

	a	e	i	Ω	ω	M
a	3.52024E-16	-5.91994E-15	-3.27560E-13	-1.12683E-13	3.58181E-14	-3.35020E-12
e	-5.91994E-15	3.35415E-13	2.93372E-11	8.78919E-12	9.74463E-13	2.78309E-11
i	-3.27560E-13	2.93372E-11	8.74093E-9	1.88324E-9	2.60793E-10	3.56453E-10
Ω	-1.12683E-13	8.78919E-12	1.88324E-9	3.35671E-9	-5.56486E-10	-2.36488E-10
ω	3.58181E-14	9.74463E-13	2.60793E-10	-5.56486E-10	9.43885E-10	-1.54532E-9
M	-3.35020E-12	2.78309E-11	3.56453E-10	-2.36488E-10	-1.54532E-9	3.87897E-8

Date of computation: 2025-05-15 00:00 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

17.555

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

800 - 1800*

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

2552

Unit

Source

[1]

Unobserved

Value

331

Unit

Source

[1]

Normalized RMS of residuals

Value

0.598381

Unit

Source

[1]

Astrometry Summary

First Observation
Last Observation
Total Optical Observations (Discarded)

Optical

Value

Unit

Source

First Observation

Value

2017-07-16.97176

Unit

Source

[2]

Last Observation

Value

2024-07-11.96096

Unit

Source

[2]

Total Optical Observations (Discarded)

Value

105 (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 2021PH27 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
VENUS	1960-01-26 13:30	1.1	0.0375912	0.0375398	0.0000171
VENUS	1960-09-06 02:26	< 1 min	0.0244196	0.0243674	0.0000174
VENUS	1976-01-23 20:30	< 1 min	0.0152954	0.0152941	0.0000004
VENUS	1991-06-11 19:27	< 1 min	0.0253384	0.0253173	0.0000070
VENUS	1992-01-21 18:10	< 1 min	0.0385377	0.0385095	0.0000094
VENUS	2006-10-29 03:02	< 1 min	0.0451540	0.0451439	0.0000033
VENUS	2007-06-09 10:24	< 1 min	0.0173759	0.0173694	0.0000022
VENUS	2022-10-26 04:45	< 1 min	0.0161827	0.0161818	0.0000003
VENUS	2038-03-14 07:51	< 1 min	0.0329366	0.0329259	0.0000036
VENUS	2038-10-24 00:41	< 1 min	0.0286965	0.0286839	0.0000042
VENUS	2054-03-11 18:15	< 1 min	0.0144893	0.0144867	0.0000009
VENUS	2069-07-28 14:32	< 1 min	0.0206215	0.0205897	0.0000106
VENUS	2070-03-09 17:31	< 1 min	0.0443666	0.0443175	0.0000164
VENUS	2084-12-14 21:37	< 1 min	0.0415220	0.0414789	0.0000144
VENUS	2085-07-26 08:12	< 1 min	0.0194532	0.0194147	0.0000128
VENUS	2100-12-13 01:51	< 1 min	0.0141162	0.0141071	0.0000031
VENUS	2116-05-01 02:09	1.3	0.0278062	0.0277314	0.0000249
VENUS	2116-12-10 23:11	< 1 min	0.0342249	0.0341314	0.0000312

Download as:

Stationary Points

Ecc. an. ast.	Ecc. an. Earth	Distance in au	Classification
172.27369499	120.72264517	0.22542919	MINIMUM
348.18748628	286.73822893	0.85849820	SADDLE
352.05261162	114.44984217	1.14156638	SADDLE
177.98484376	302.76487011	1.77992572	MAXIMUM

Download:

MOID Plots

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