The M87 black hole, also known as Messier 87* (M87*), is a supermassive black hole located at the center of the giant elliptical galaxy Messier 87. This black hole gained widespread attention in April 2019 when the Event Horizon Telescope (EHT) collaboration released the first-ever image of a black hole, capturing the silhouette of the M87 black hole’s event horizon. Here are key details about the M87 black hole:

1. Galaxy and Location:
   • Messier 87 (M87) is a massive elliptical galaxy located in the Virgo Cluster, approximately 55 million light-years away from Earth. The M87 black hole resides at the galaxy’s center.
2. Supermassive Black Hole:
   • The M87 black hole is a supermassive black hole, meaning it has a mass equivalent to billions of times that of our Sun. Its estimated mass is about 6.5 billion solar masses.
3. Event Horizon Telescope (EHT) Observations:
   • The Event Horizon Telescope is a global collaboration of radio telescopes synchronized to create a virtual Earth-sized telescope. In April 2019, the EHT collaboration released the first image of the event horizon of a black hole, providing a historic visual confirmation of the existence of black holes.
4. Image Characteristics:
   • The EHT image shows the shadow of the black hole against the glow of hot, ionized gas swirling around it. The bright ring-like structure is caused by gravitational lensing, a phenomenon predicted by Albert Einstein’s theory of general relativity.
5. Event Horizon:
   • The event horizon is the boundary around a black hole beyond which nothing, not even light, can escape. The EHT image provides a direct observation of the event horizon of the M87 black hole.
6. Jet of High-Speed Particles:
   • M87 is also known for its powerful jet of high-speed particles that extends for thousands of light-years. This jet is thought to be powered by the black hole’s gravitational energy.
7. Gravity and Light Bending:
   • The extreme gravity near the black hole causes light to bend, leading to the distorted appearance of space around it. This effect is known as gravitational lensing.
8. Scientific Significance:
   • Observations of the M87 black hole provide valuable insights into the nature of black holes, the behavior of matter under extreme conditions, and the validity of general relativity in such environments.
9. Subsequent Observations:
   • The EHT collaboration continues to study the M87 black hole and other black holes. Subsequent observations aim to refine measurements, study variability, and deepen our understanding of the physics near black holes.

The observation of the M87 black hole marked a historic achievement in astrophysics, offering a visual confirmation of theoretical predictions and opening new avenues for studying the extreme environments near supermassive black holes.