A stellar black hole is a black hole formed by the gravitational collapse of a massive star. They have masses ranging from about 5 to several tens of times the mass of the Sun. They are invisible directly but can be detected by their interaction with nearby matter.
The Orion Spur is a minor spiral arm of the Milky Way between the Sagittarius and Perseus arms. Our Solar System is located within this spur, also known as the Local Arm.