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Asteroid

Isis

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42 Isis (A856 KB)

Where is it now

Distance from Sun
2.985 AU
True anomaly
184.13°
Distance from Earth
3.672 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 Isis — 2.985 AU from the Sun Isis
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. Isis is 3.672 AU from Earth today (30.5 light-minutes).

In the sky

Right ascension
10h 49m 42s
Declination
+14° 02′ 57″
Constellation
Leo
Distance from Earth
3.66 AU
Elongation from the Sun
41.05° — near the Sun — look low at dusk or dawn

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
2.445 AU
Eccentricity
0.222
Inclination
8.5°
Orbital period
3.82 years
Perihelion
1.902 AU
Aphelion
2.988 AU
Longitude of ascending node
84.15°
Argument of periapsis
237.62°
Epoch · J2000
2461200.5
Orbit class · MBA
Main-belt asteroid
Earth MOID · 351.8 LD
0.904 AU
Tisserand (Jupiter)
3.45

Orbit quality

Orbit very well determined (uncertainty code 0).

Observations used
9,006
Data arc
169.8 years
First observed
20 June 1856
Last observed
7 April 2026
Residual RMS
0.34 ″
Solution · Otto Matic
5 June 2026

Physical properties

Mean radius
55 km
Rotation period
13.59 hours

Visual & observation

Geometric albedo
0.139
Absolute magnitude (H)
7.69
Colour index (B–V)
0.87
Spectral type (SMASS)
L
Spectral type (Tholen)
S
Colour index (U–B)
0.46

Discovery & classification

Discovered by
Pogson, N. R.
Discovery date
23 May 1856
Discovery site
Oxford

Also known as 42 · A856 KB · 1939 GM · 1950 DD1 · A910 TA

Main-Belt Asteroid Named

Sources