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Visit Sgr A*: v0.4.0-dev.23 and dev.24

Sunholo
Sunholo
Stapledon's Voyage team

The black-hole milestone is done: you can fly to the supermassive black hole at the centre of the Galaxy, hover above it and orbit it, with general relativity in the physics and in the picture.

Sgr A* from the bridge at 10 Schwarzschild radii

Sgr A* aboard the ship​

Choose "Sgr A* (black hole)" in navigation. The ship approaches from 1.3 light years, then hovers at 10, 5 and 3 Schwarzschild radii and orbits at 3. The HUD reads the simulation:

  • Clocks. At 10 r_s, 1 ship-hour is 1.054 home hours; in orbit at 3 r_s it is 1.41. The time you spend near the hole really accumulates on both clocks.
  • Light. It shows the shadow's size and the blueshift of incoming light.
  • Forces. It shows the tide across the bubble, and the hover thrust, which the crew never feels.

Built package-first​

  • The maths. sunholo/relativity 0.10.0 adds a geodesic integrator, cross-checked against the exact solution to 3e-13.
  • The lens tables. They are generated on the AILANG VM and pinned.
  • The shader. A GPU shader mirrors the CPU reference pixel for pixel.
  • The checks. The shadow matches Synge's formula to within 0.01 px at 10, 5 and 3 r_s, and a star directly behind the hole makes an Einstein ring at the predicted angle. R1's black-hole requirements are met.

Also​

  • A light-speed loading screen. Picking a menu option accelerates the real sky to 0.99999c, where it collapses into a point, then a white-out into the ship. Loading itself is 3 to 4 times faster.
  • A Main menu button on the galaxy map.
  • dev.24 fixes dev.23. The exported app was missing the lens tables, so the hole was invisible. Publishing now checks them inside the exported app.

Releases: v0.4.0-dev.23-black-hole, v0.4.0-dev.24-lens-fix · Gallery.