What telescope do I need to see Irene?

At magnitude 8.6, Irene is within reach of a 3-inch (80 mm) telescope from a moderate-Bortle site.

Irene — Astéroïde dans Sagittarius

14 Irene

Asteroid Sagittarius Visible

Rendered preview of Irene from the Nightbase orrery, lit from the current Sun direction with the terminator visible.

Carte du Ciel Système Solaire 3D + Liste + Plan

Propriétés

Magnitude 8.6

Description

Type: Asteroid

Distance: 2.588 AU

Orbital Period: 1520.6 days

Diameter: 152 km

Greek goddess of peace; S-type; reaches mag 8.6 at perihelic oppositions, near the binocular limit.

Position et Identifiants

RA 18h 04m 09.6s

Dec -20° 03' 31.9"

Constellation Sagittarius

Catalogue Irene

Wikipedia

Propriétés Physiques

Diamètre 152 km

Masse 5.6e18 kg

Albédo 0.16 (16% reflected)

Rotation 15.0 hours

Taille angulaire 0.1″ (current)

Propriétés orbitales

Demi-grand axe 2.5879 AU (387.1 million km)

Excentricité 0.1627

Inclinaison 9.13°

Période orbitale 4.16 years

Distance 1.605 AU (13.4 light-min)

Élongation 128.8° Good

Brightness Forecast (next 12 months)

Apparent magnitude as Earth–asteroid distance changes through the year. The peak marks the brightest moment in the window — usually around opposition, when the asteroid is closest and fully illuminated.

Computed from JPL orbital elements via m = H + 5·log₁₀(r·Δ). Phase-function correction is omitted, so curves trace distance variation only — accurate within a few tenths for main-belt asteroids; coarse for fast-moving NEOs near Earth.