When to Use Sagittarius A* Star Orbit 3D Explorer
Open the Sagittarius A* Star Orbit 3D Explorer when you need to see how astronomers actually weighed a black hole they cannot photograph - a real, measured star orbit rendered from its own published elements, not a generic teaching ellipse.
A five-minute classroom demo
A five-minute classroom demo starts when you open the explorer, drag the slider to pericenter so S2 visibly speeds up, then read the mass figure in the panel and explain that the same measured orbit produced that number - no photograph of the black hole required.
Understanding how black hole masses get measured
Understanding how black hole masses get measured is exactly the question this page answers: a star's orbital period and size depend only on the mass it orbits, so tracking S2 for one full 16-year cycle gave astronomers Sgr A*'s mass to within about 0.3% precision.
Sessions Sagittarius A* Star Orbit 3D Explorer does not fit
Sessions Sagittarius A* Star Orbit 3D Explorer does not fit are live tracking of S2's actual current position, or any general-relativity calculation - the scene renders the plain Newtonian ellipse from the published elements, not a live feed and not a GR precession model. For an artistic render of the black hole itself, use the Black Hole 3D Explorer; for a generic teaching orbit with adjustable eccentricity, use Kepler Orbits 3D Explorer.
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