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Asteroid

Irma

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177 Irma (A877 VA)

Where is it now

Distance from Sun
3.184 AU
True anomaly
139.02°
Distance from Earth
3.963 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 Irma — 3.184 AU from the Sun Irma
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. Irma is 3.963 AU from Earth today (33.0 light-minutes).

In the sky

Right ascension
11h 43m 58s
Declination
+01° 45′ 44″
Constellation
Virgo
Distance from Earth
3.96 AU
Elongation from the Sun
33.76° — 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
2.772 AU
Eccentricity
0.2352
Inclination
1.38°
Orbital period
4.61 years
Perihelion
2.12 AU
Aphelion
3.424 AU
Longitude of ascending node
346.87°
Argument of periapsis
39.73°
Epoch · J2000
2461200.5
Orbit class · MBA
Main-belt asteroid
Earth MOID · 437.1 LD
1.1232 AU
Tisserand (Jupiter)
3.296

Orbit quality

Orbit very well determined (uncertainty code 0).

Observations used
6,140
Data arc
125.5 years
First observed
23 October 1900
Last observed
12 April 2026
Residual RMS
0.37 ″
Solution · Otto Matic
5 June 2026

Physical properties

Mean radius
35 km
Rotation period
13.86 hours

Visual & observation

Geometric albedo
0.022
Absolute magnitude (H)
9.62
Colour index (B–V)
0.73
Spectral type (SMASS)
Ch
Spectral type (Tholen)
C:
Colour index (U–B)
0.35

Discovery & classification

Discovered by
Henry, P. P.
Discovery date
5 November 1877
Discovery site
Paris

Also known as 177 · A877 VA · 1937 UA · 1962 DB · A900 UB · A900 VA · A912 HE

Main-Belt Asteroid Named

Sources