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Asteroid Near-Earth

2017 BN123

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(2017 BN123)

Where is it now

Distance from Sun
0.572 AU
True anomaly
356.8°
Distance from Earth
0.935 AU
As of
20 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 — 0.996 AU from the Sun Earth 2017 BN123 — 0.572 AU from the Sun 2017 BN123
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. 2017 BN123 is 0.935 AU from Earth today (7.8 light-minutes).

In the sky

Right ascension
15h 58m 18s
Declination
-23° 07′ 26″
Constellation
Scorpius
Distance from Earth
0.93 AU
Elongation from the Sun
34.41° — near the Sun — look low at dusk or dawn

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
0.891 AU
Eccentricity
0.3578
Inclination
25.21°
Orbital period
307.2 days
Perihelion
0.572 AU
Aphelion
1.21 AU
Longitude of ascending node
330.65°
Argument of periapsis
351.94°
Epoch · J2000
2461200.5
Orbit class · ATE
Aten
Earth MOID · 79.1 LD
0.2032 AU
Tisserand (Jupiter)
6.539

Orbit quality

Orbit very well determined (uncertainty code 1).

Observations used
53
Data arc
21.03 years
First observed
26 January 2001
Last observed
7 February 2022
Residual RMS
0.65 ″
Solution · Otto Matic
22 November 2023

Visual & observation

Absolute magnitude (H)
22.6

Discovery & classification

Aten Near-Earth Object

Close approaches 183 on record

Flyby geometry
Ecliptic flyby of 2017 BN123 at 2027-01-11 22:20 UTC Top-down view of the ecliptic, Earth at the centre, for the 2027-01-11 22:20 UTC close approach of 2017 BN123. Catalogue miss distance 163.0 LD · 6.27 × 10⁷ km. The curve is the geocentric path from 2027-01-08 to 2027-01-14, 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. At closest approach the object is north of the ecliptic. The path is a geocentric ecliptic ephemeris from JPL Horizons. The inset is a heliocentric view and is approximate. Sun 163.0 LD · 6.27 × 10⁷ km 2027-01-11 22:20 UTC Earth Moon Heliocentric, approximate

Top-down view of the ecliptic, Earth at the centre, for the 2027-01-11 22:20 UTC close approach of 2017 BN123. Catalogue miss distance 163.0 LD · 6.27 × 10⁷ km. The curve is the geocentric path from 2027-01-08 to 2027-01-14, 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. At closest approach the object is north of the ecliptic. The path is a geocentric ecliptic ephemeris from JPL Horizons. The inset is a heliocentric view and is approximate.

JPL Horizons

When (UTC) Body Distance Lunar distances Relative speed
2027-01-11 22:20:00 Earth 0.419 AU 163.0 LD 18.2 km/s
2027-08-30 08:51:00 Earth 0.4343 AU 169.0 LD 22.7 km/s
2028-03-05 06:40:00 Earth 0.2068 AU 80.5 LD 14.5 km/s
2032-09-26 02:46:00 Earth 0.4322 AU 168.2 LD 20.6 km/s
2033-02-18 04:43:00 Earth 0.2236 AU 87.0 LD 14 km/s
2033-06-22 03:50:00 Earth 0.4859 AU 189.1 LD 17.3 km/s
2037-10-31 08:23:00 Earth 0.4389 AU 170.8 LD 14.8 km/s
2038-02-01 01:23:00 Earth 0.2799 AU 108.9 LD 14.1 km/s
2038-07-23 08:39:00 Earth 0.4651 AU 181.0 LD 21.8 km/s
2039-03-13 20:28:00 Earth 0.3816 AU 148.5 LD 20.7 km/s

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

Sources