“Very soon the heavens presented an extraordinary appearance, for all the stars directly behind me were now deep red, while those directly ahead were violet,” is how philosopher and science-fiction author Olaf Stapledon described the phenomena known as “redshift” in his science fiction novel, Star Maker, a history of life in the universe. In 1929, Edwin Hubble discovered that the universe is expanding, with most other galaxies moving away from us. Light from these galaxies is shifted to longer (further away and redder) wavelengths – in other words, it is red-shifted, a result of the expansion of the universe.
On April 10, 2019 the astronomers at Harvard’s Black Hole Initiative were asking what does the glowing bright orange ring around the now iconic black hole the size of our solar system at the center of the monster elliptical galaxy M87 –the largest, most massive galaxy in the nearby universe–mean? according to Harvard Event Horizon Telescope radio astronomer, Michael Johnson.
Albert Einstein described black holes as strange objects “where God divided by zero.” An international team of astrophysicists has now confirmed that black holes are a distinct “species” from neutron stars –comparable to black holes in mass and size but confined within a hard surface, unlike black holes, an exotic cosmic object without a hard surface predicted by Einstein’s theory of General Relativity that do not have a surface, and are confined within an invisible boundary, called an event horizon, from within which nothing, not even light, can escape.
Noble-Prize laureate Subrahmanyan Chandrasekhar, for whom NASA’s Chandra X-Ray Observatory was named, described black holes as “the most perfect macroscopic objects there are in the universe: the only elements in their construction are our concepts of space and time,” which has inspired astrophysicists to question how big these paradoxical objects, these “Gates of Hell” might become?
“Einstein’s gravitational theory, said to be the greatest single achievement of theoretical physics, resulted in beautiful relations connecting gravitational phenomena with the geometry of space,” said the great Caltech physicist Richard Feynman. For all its vast voids, the universe is rippling with ghostly gravitational waves produced by extreme astrophysical phenomena, vibrating the fabric of space-time, like the ringing of a cosmic bell.
Astronomers have discovered a rare dual quasar–a quasi-stellar radio source, one of the most luminous, powerful engines known in the universe, powered by supermassive black holes that are millions to billions times more massive than our Sun– that existed 4.6 billion years ago, 13,000 light years apart near the center of a single massive galaxy. By comparison, the gargantuan explosion of a single supernova can outshine an entire galaxy for a few weeks; a single quasar can outshine 10,000 galaxies for millions of years.
