Stars much more massive than our Sun can eventually form black holes at the end of their life cycle.
Describe how a black hole is formed from such a massive star.
The high-mass X-ray binary system Cygnus X-1 contains one of the first widely accepted stellar-mass black holes. The system is approximately 610061006100 light-years from the Earth.
Explain what is meant by the unit light-year.
Calculate the approximate distance from Cygnus X-1 to the Earth in kilometres km\text{km}km. Give your answer in standard form to 2 significant figures.
25 exam-style questions on CIE IGCSE Physics 6.2.2a Galaxies and astronomical distances. Each one has a worked solution and a mark scheme showing where the marks go.