What telescope do I need to see Sylvia?

At magnitude 11.0, Sylvia is best observed with a 6-inch (150 mm) or larger telescope.

Sylvia — Asteroid in Gemini

87 Sylvia

Asteroid Gemini Visible

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

Star Map 3D Solar System + List + Plan

Properties

Magnitude 11.0

Description

Type: Asteroid

Distance: 3.485 AU

Orbital Period: 2375.8 days

Diameter: 261 km

X/P-type triple system — orbited by two small moons, Romulus (2001) and Remus (2004). Outer-belt orbit at 3.48 AU; very dark, reddish surface.

Position & Identifiers

RA 06h 16m 21.0s

Dec +28° 42' 01.9"

Constellation Gemini

Catalog Sylvia

Wikipedia

Physical Properties

Diameter 261 km

Mass 1.5e19 kg

Albedo 0.05 (5% reflected)

Rotation 5.2 hours

Angular Size 0.1″ (current)

Orbital Properties

Semi-major Axis 3.4845 AU (521.3 million km)

Eccentricity 0.0943

Inclination 10.87°

Orbital Period 6.50 years

Distance 4.168 AU (34.7 light-min)

Elongation 53.9° Moderate

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.