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 — Asteroide em Sagittarius

14 Irene

Asteroid Sagittarius Visível

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

Mapa Estelar Sistema Solar 3D + Lista + Plano

Propriedades

Magnitude 8.6

Descrição

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.

Posição e Identificadores

RA 18h 04m 09.6s

Dec -20° 03' 31.9"

Constelação Sagittarius

Catálogo Irene

Wikipedia

Propriedades Físicas

Diâmetro 152 km

Massa 5.6e18 kg

Albedo 0.16 (16% reflected)

Rotação 15.0 hours

Tamanho angular 0.1″ (current)

Propriedades orbitais

Semieixo maior 2.5879 AU (387.1 million km)

Excentricidade 0.1627

Inclinação 9.13°

Período orbital 4.16 years

Distância 1.605 AU (13.4 light-min)

Elongação 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.