2021 BZ is an asteroid in the Aten orbit class. Its orbit takes it from 0.69 AU to 1.3 AU from the Sun; one orbit takes 362.2 days. Orbit from the JPL solution of 24 October 2024.
Where is it now
- Distance from Sun
- 1.26 AU
- True anomaly
- 201.02°
- Distance from Earth
- 0.823 AU
- As of
- 2 November 2026
Two-body Kepler propagation — accurate to ~0.1% for major planets over decades, less so for highly-perturbed bodies. Use JPL Horizons for high precision.
In the sky
- Right ascension
- 08h 39m 17s
- Declination
- -05° 00′ 01″
- Constellation
- Hydra
- Distance from Earth
- 0.81 AU
- Elongation from the Sun
- 87.76° — well clear of the Sun
Visible from both hemispheres.
From your location
See how high it is right now, whether it is up after civil twilight, and when it rises and sets where you are.
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Two-body approximation, good to about a degree for the planets — enough to find the constellation and know whether it is up.
Orbital elements
- Semi-major axis
- 0.994 AU
- Eccentricity
- 0.3044
- Inclination
- 19.29°
- Orbital period
- 362.2 days
- Perihelion
- 0.692 AU
- Aphelion
- 1.297 AU
- Longitude of ascending node
- 126.53°
- Argument of periapsis
- 109.56°
- Epoch · J2000
- 2461200.5
- Orbit class · ATE
- Aten
- Earth MOID · 5.5 LD
- 0.0142 AU
- Tisserand (Jupiter)
- 6.018
Orbit quality
Orbit very well determined (uncertainty code 1).
- Observations used
- 62
- Data arc
- 728 days
- First observed
- 29 January 2020
- Last observed
- 26 January 2022
- Residual RMS
- 0.36 ″
- Solution · Otto Matic
- 24 October 2024
Visual & observation
- Absolute magnitude (H)
- 24.76
Discovery & classification
Close approaches 130 on record
Top-down view of the ecliptic, Earth at the centre, for the 2027-01-19 10:23 UTC close approach of 2021 BZ. Catalogue miss distance 110.1 LD · 4.23 × 10⁷ km. The curve is the geocentric path from 2027-01-16 to 2027-01-22, with a mark at UTC midnights and an arrow for the direction of motion. The circle is the Moon’s mean orbit; the Moon is plotted at closest approach. A ray shows the Sun’s direction. The labelled distance is the full separation. The drawn radius is the part that lies in the ecliptic plane. The path is a geocentric ecliptic ephemeris from JPL Horizons. The inset is a heliocentric view and is approximate.
| When (UTC) | Body | Distance | Lunar distances | Relative speed |
|---|---|---|---|---|
| 2027-01-19 10:23:00 | Earth | 0.2829 AU | 110.1 LD | 20.7 km/s |
| 2028-01-17 17:23:00 | Earth | 0.333 AU | 129.6 LD | 22.1 km/s |
| 2029-01-14 23:49:00 | Earth | 0.383 AU | 149.0 LD | 23.6 km/s |
| 2030-01-13 04:30:00 | Earth | 0.4329 AU | 168.5 LD | 25 km/s |
| 2031-01-11 07:14:00 | Earth | 0.4838 AU | 188.3 LD | 26.5 km/s |
| 2035-04-08 12:34:00 | Venus | 0.1064 AU | 41.4 LD | 11.9 km/s |
| 2053-02-09 13:59:00 | Venus | 0.0914 AU | 35.6 LD | 13.8 km/s |
| 2083-11-14 13:49:00 | Venus | 0.091 AU | 35.4 LD | 13.8 km/s |
| 2101-09-20 02:05:00 | Venus | 0.1437 AU | 55.9 LD | 17 km/s |
| 2110-09-18 11:17:00 | Earth | 0.4566 AU | 177.7 LD | 24.3 km/s |
Next ten from today. 1 lunar distance = 384,400 km. Source: JPL close-approach data.
Sources
- visual properties: JPL SBDB (lookup)
- orbital elements: JPL SBDB