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Asteroid

Aethra

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132 Aethra (A873 LA)

Where is it now

Distance from Sun
3.613 AU
True anomaly
185.4°
Distance from Earth
3.154 AU
As of
22 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.

Orbit of Mercury Orbit of Venus Orbit of Mars Sun Earth — 0.995 AU from the Sun Earth Aethra — 3.613 AU from the Sun Aethra
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. Aethra is 3.154 AU from Earth today (26.2 light-minutes).

In the sky

Right ascension
21h 00m 51s
Declination
+12° 48′ 05″
Constellation
Delphinus
Distance from Earth
3.16 AU
Elongation from the Sun
109.06° — 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.

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
2.612 AU
Eccentricity
0.3871
Inclination
24.98°
Orbital period
4.22 years
Perihelion
1.601 AU
Aphelion
3.623 AU
Longitude of ascending node
258.04°
Argument of periapsis
255.63°
Epoch · J2000
2461200.5
Orbit class · MCA
Mars-crossing asteroid
Earth MOID · 304.4 LD
0.7822 AU
Tisserand (Jupiter)
3.176

Orbit quality

Orbit very well determined (uncertainty code 0).

Observations used
5,574
Data arc
152.4 years
First observed
14 June 1873
Last observed
9 November 2025
Residual RMS
0.3 ″
Solution · Otto Matic
5 June 2026

Physical properties

Mean radius
21 km
Rotation period
5.17 hours

Visual & observation

Geometric albedo
0.199
Absolute magnitude (H)
8.96
Colour index (B–V)
0.67
Spectral type (SMASS)
Xe
Spectral type (Tholen)
M
Colour index (U–B)
0.19

Discovery & classification

Discovered by
Watson, J. C.
Discovery date
13 June 1873
Discovery site
Ann Arbor

Also known as 132 · A873 LA · 1949 MD · 1953 LF · A922 XB

Mars-crosser Named

Sources