Space VLBI Baseline & Resolution Simulator

Array mode

Parameters

Observing wavelength 6.0 cm

Single-dish diameter 100 m

Active ground dishes 4

Space antenna distance 350,000 km

Orbit speed 1.0x

Readouts

Max baseline

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Ang. resolution

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vs single dish

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Active antennas

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How resolution scales

A telescope's diffraction-limited angular resolution is

θ ≈ 1.22 · λ / D

where λ is the observing wavelength and D is the aperture — for an interferometer, D is replaced by the longest baseline between any two antennas in the array. A single dish is capped by how large a dish can physically be built. Combining dishes across Earth extends D up to Earth's diameter. Adding one antenna in distant orbit (like RadioAstron's elliptical orbit reaching ~350,000 km) extends the effective baseline far beyond Earth itself, shrinking θ by orders of magnitude.

Single 100 m dish @ 6 cm: θ ≈ 150 milliarcsec
Earth VLBI (12,700 km baseline): θ ≈ 1 milliarcsec
Space VLBI (350,000 km baseline): θ ≈ 0.04 milliarcsec

Drag to orbit the camera · scroll/pinch to zoom.

Ground dish (active) Ground dish (idle) Space antenna Baseline (max) Distant radio source

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Resolved image of the radio source

What you're seeing

Only the bright core is visible — the double-lobe jet structure is far below this array's resolving power.

Mode

Single Dish