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Asteroid

Astraea

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5 Astraea (A845 XA)

Where is it now

Distance from Sun
3.01 AU
True anomaly
201.85°
Distance from Earth
2.278 AU
As of
11 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 — 0.998 AU from the Sun Earth Astraea — 3.01 AU from the Sun Astraea
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. Astraea is 2.278 AU from Earth today (18.9 light-minutes).

In the sky

Right ascension
22h 03m 05s
Declination
-14° 41′ 22″
Constellation
Aquarius
Distance from Earth
2.28 AU
Elongation from the Sun
128.58° — 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
2.577 AU
Eccentricity
0.1876
Inclination
5.36°
Orbital period
4.14 years
Perihelion
2.093 AU
Aphelion
3.06 AU
Longitude of ascending node
141.45°
Argument of periapsis
359.38°
Epoch · J2000
2461200.5
Orbit class · MBA
Main-belt asteroid
Earth MOID · 430.7 LD
1.1066 AU
Tisserand (Jupiter)
3.396

Orbit quality

Orbit very well determined (uncertainty code 0).

Observations used
4,395
Data arc
179.8 years
First observed
15 December 1845
Last observed
19 October 2025
Residual RMS
0.48 ″
Solution · Otto Matic
11 March 2026

Physical properties

Mean radius
53 km
Rotation period
16.81 hours

Visual & observation

Geometric albedo
0.274
Absolute magnitude (H)
6.95
Colour index (B–V)
0.83
Spectral type (SMASS)
S
Spectral type (Tholen)
S
Colour index (U–B)
0.41

Discovery & classification

Discovered by
Hencke, K. L.
Discovery date
8 December 1845
Discovery site
Driesen

Also known as 5 · A845 XA · 1969 SE

Main-Belt Asteroid Named

Close approaches 4 on record

When (UTC) Body Distance Lunar distances Relative speed
2092-08-23 07:36:00 Juptr 1.9784 AU 769.9 LD 2.1 km/s
2187-11-27 19:51:00 Juptr 1.9514 AU 759.4 LD 2.1 km/s

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

Sources