An X-ray quiet black hole born with a negligible kick in a massive binary within the Large Magellanic Cloud

Understand

Stellar-mass black holes are the final remnants of stars born with more than 15 solar masses.

• Billions are expected to reside in the Local Group, yet only few are known, mostly detected through X-rays emitted as they accrete material from a companion star.
• Here, we report on VFTS 243: a massive X-ray faint binary in the Large Magellanic Cloud.
• With an orbital period of 10.4-d, it comprises an O-type star of 25 solar masses and an unseen companion of at least nine solar masses.