Summary:

- Astronomers have discovered a remarkable cosmic explosion that was hidden for years, known as the "Cow" event.
- The Cow event was a rare and mysterious fast-evolving luminous transient that was first detected in 2018, and it has been the subject of intense study since then.
- Observations suggest that the Cow event may have been the result of the birth of a black hole or neutron star, and it could provide insights into the early stages of these extreme cosmic phenomena.