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Asteroid Near-Earth

2021 JB

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(2021 JB)

Where is it now

Distance from Sun
1.136 AU
True anomaly
149.58°
Distance from Earth
2.028 AU
As of
21 October 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.

Sun Earth — 0.995 AU from the Sun Earth 2021 JB — 1.136 AU from the Sun 2021 JB
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. 2021 JB is 2.028 AU from Earth today (16.9 light-minutes).

In the sky

Right ascension
15h 01m 12s
Declination
-18° 35′ 36″
Constellation
Libra
Distance from Earth
2.03 AU
Elongation from the Sun
19.05° — too close to the Sun to observe

Favours the southern hemisphere; low or below the horizon from far north.

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.

How do I find my coordinates?

Google Maps on a computer

  1. Right-click the spot where you'll be observing.
  2. The first line of the menu is the coordinates, e.g. 51.50722, -0.12758 — click it and they're copied.
  3. Paste them above.

Google Maps on a phone

  1. Press and hold the spot to drop a pin.
  2. The coordinates appear in the search bar (or on the pin's card) — tap to copy, then paste above.

A full Google Maps link works too, but the short maps.app.goo.gl share links don't carry coordinates — copy the numbers instead. We round to about a kilometre; that's all the sky calculation needs.

Know your what3words address? Paste it, e.g. ///filled.count.soap. This is optional — the three words are sent to what3words to convert them, and we don't store the address or the result.

Your location stays in your browser and is sent only for this calculation. Using a what3words address is optional; if you do, the three words go to what3words to be converted and we don't record them. Set a location first, then you can save an email alert for this object. See our privacy policy.

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
0.931 AU
Eccentricity
0.2874
Inclination
6.68°
Orbital period
328.1 days
Perihelion
0.663 AU
Aphelion
1.199 AU
Longitude of ascending node
42.73°
Argument of periapsis
51.97°
Epoch · J2000
2461200.5
Orbit class · ATE
Aten
Earth MOID · 4.6 LD
0.0118 AU
Tisserand (Jupiter)
6.394

Orbit quality

Orbit reasonably well determined (uncertainty code 4).

Observations used
41
Data arc
7 days
First observed
1 May 2021
Last observed
8 May 2021
Residual RMS
0.39 ″
Solution · Otto Matic
22 May 2021

Visual & observation

Absolute magnitude (H)
26.69

Discovery & classification

Aten Near-Earth Object

Close approaches 149 on record

Flyby geometry
Ecliptic flyby of 2021 JB at 2029-05-15 07:45 UTC Top-down view of the ecliptic, Earth at the centre, for the 2029-05-15 07:45 UTC close approach of 2021 JB. Catalogue miss distance 192.5 LD · 7.4 × 10⁷ km. The curve is the geocentric path from 2029-05-12 to 2029-05-18, 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 approximate: a two-body Kepler propagation of the catalogue orbital elements, not a numerical integration. The Moon’s position is approximate. The inset is a heliocentric view and is approximate. approximate Sun 192.5 LD · 7.4 × 10⁷ km 2029-05-15 07:45 UTC Earth Moon Heliocentric, approximate

Top-down view of the ecliptic, Earth at the centre, for the 2029-05-15 07:45 UTC close approach of 2021 JB. Catalogue miss distance 192.5 LD · 7.4 × 10⁷ km. The curve is the geocentric path from 2029-05-12 to 2029-05-18, 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 approximate: a two-body Kepler propagation of the catalogue orbital elements, not a numerical integration. The Moon’s position is approximate. The inset is a heliocentric view and is approximate.

When (UTC) Body Distance Lunar distances Relative speed
2029-05-15 07:45:00 Earth 0.4947 AU 192.5 LD 23.1 km/s
2030-05-07 02:14:00 Earth 0.1068 AU 41.6 LD 6.2 km/s
2030-12-13 22:11:00 Earth 0.323 AU 125.7 LD 11.4 km/s
2031-08-29 09:22:00 Earth 0.117 AU 45.5 LD 9.3 km/s
2031-12-13 21:41:00 Venus 0.0977 AU 38.0 LD 12.3 km/s
2033-08-02 02:42:00 Venus 0.054 AU 21.0 LD 10.5 km/s
2038-05-09 19:11:00 Earth 0.3592 AU 139.8 LD 18.9 km/s
2039-02-28 17:19:00 Earth 0.2608 AU 101.5 LD 6.5 km/s
2039-06-06 19:46:00 Earth 0.1884 AU 73.3 LD 6.5 km/s
2039-11-22 11:25:00 Earth 0.2989 AU 116.3 LD 10.4 km/s

Next ten from today. 1 lunar distance = 384,400 km. Source: JPL close-approach data.

Sources