Schwarzschild Radius & Event HorizonMathematics

Black Hole Schwarzschild Radius & Event Horizon General Relativity Calculator

Calculate theoretical non-rotating Schwarzschild black hole Event Horizon radius (Rs = 2GM/c²), Photon Sphere (1.5 Rs), and Innermost Stable Circular Orbit (ISCO = 3.0 Rs) from solar masses.

Calculator Inputs

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M_sun
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Calculated ResultSchwarzschild Radius & Event Horizon

Schwarzschild Event Horizon Radius (Rs in km)

29.53km

Photon Sphere Radius (1.5 Rs km)

44.3 km

Innermost Stable Orbit (ISCO = 3.0 Rs km)

88.59 km

Event Horizon Total Diameter (km)

59.06 km

Radius in Astronomical Units (AU)

0 AU

General Relativity Solution: Accurately maps the boundary where spacetime curvature prevents light escape.

Black Hole Spacetime Horizons

Event Horizon Rs
29.53 km(18%)
Photon Sphere
44.3 km(27%)
ISCO Orbit
88.59 km(55%)

Detailed Calculation Breakdown

Event Horizon Rs
29.53 km
Photon Sphere
44.3 km
ISCO Orbit
88.59 km

Calculation Methodology

Schwarzschild Radius: Rs = (2 * G * M) / c^2 ≈ 2.95325 km per Solar Mass (M_☉). Photon Sphere Radius = 1.5 * Rs. Innermost Stable Circular Orbit (ISCO) = 3.0 * Rs.

Important Legal & Educational Disclaimer

This theoretical astrophysics and general relativity tool computes spacetime curvature horizons.

This calculator is designed for educational and informational purposes only based on public statutory frameworks. The outputs do not constitute binding financial, tax, or legal advice. We assume no liability for decisions made based on these estimations. Always verify with the relevant official authorities or a certified professional advisor.

Frequently Asked Questions

Approximately 8.87 millimeters (about the size of a marble or peanut).
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