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Behold this stunning 3D model of some of the activity around the really massive Black Hole at the center of our lovely galaxy. It’s called Sagittarius A* and is some 4 million times more massive than our Sun.

Humanity banded together to take a ‘photo’ of it in 2017. This video’s from that year. The data involved in making it¹ was proof-positive that there’s a Black Hole at the center of our galaxy. Professors Andrea Ghez and Reinhard Genzel shared a Nobel Prize (with Roger Penrose) in 2020 for their work leading up to this discovery.

Each second of this is two years and it’s happening ~25,000 light years away from us. Young stars are in green, old ones are in orange. We do not know the age of the stars in magenta.

S2 #

At the end of the video, you see “Orbits extrapolated from 1893 - 2013”. There are two star orbits that they did not extrapolate and actually observed completely. These stars are named S2, which makes a full loop in ~16 years, and S102, which does this is ~12 years. Here’s a video showing S2 (note the top right!)

This is space and the numbers are always crazy so here goes: S2 has a highly egg-shaped orbit and gets to ~120 times the distance between us and the Sun² at its closest approach where, this enormous thing that’s ~14 times the mass of our Sun is moving at 3% the speed of light (~5,600 miles/second, ~9,000 km/second). At highway speeds, it would take you 10 million years to complete its orbit.

I wonder if we’ll ever truly comprehend the truly staggering scales involved in the architecture of existence. Electrons, atoms, galaxies, Black Holes. Like teaching a gnat calculus. Oh well. Here’s a guy driving to the nearest star:

Update #

Here’s a video from the European Southern Observatory that zooms in to the Giant Black Hole at The Center of Our Galaxy that shows the aforementioned star (S2) looping around it.