Overview:
A new discovery places the closest black hole to our planet at a mere 1,600 light-years.
The Gaia spacecraft, launched in 2013 by the European Space Agency, has the job of precisely mapping billions of stars. Its wealth of data provides the diet for many scientists looking for any number of phenomena.
One such person has been astrophysicist Kareem El-Badry, who together with colleagues has discovered a distant star that exhibits the push-pull of gravitational forces suggesting that a “tranquil” or “dormant” black hole is nearby. After further studies using the Gemini North telescope on Hawai’i that have supported this black hole idea, the team reported their findings in the Monthly Notices of the Royal Astronomical Society.
“Take the solar system, put a black hole where the sun is, and the sun where the Earth is, and you get this system,” explained Kareem El-Badry. “While there have been many claimed detections of systems like this, almost all these discoveries have subsequently been refuted. This is the first unambiguous detection of a sun-like star in a wide orbit around a stellar-mass black hole in our galaxy.”
This black hole, with a mass about ten times that of our sun, has now been labeled as the closest one to Earth at 1,560 light-years from our pale blue dot. This will likely be another discovery in a line of such finds that will lead to closer black holes than what has now been dubbed Gaia BH1. This is because most experts think there are about 100 million black holes in the Milky Way, our galaxy, alone. Almost all of them, however, are invisible.
The existence of black holes presents something of a problem for religious believers who believe that the universe is fine-tuned for life. That is like building a rabbit hutch and run for your favorite bunnies, but also placing a vaporizer in the far corner of the garden that would cause instant death to those beloved rabbits if they approached it. Something of an odd creative choice. The universe is arguably better tuned for death.
When the next round of data is due to be released in 2025, Kareem El-Badry will be waiting expectantly. “We think there are probably a lot that are closer,” he says. “Just finding one … suggests there are a bunch more to be found.”