A tiny dwarf galaxy, ESO 495-21, three percent the size of the Milky Way, harbors a supermassive black hole that may offer clues as to how black holes and galaxies evolved in the early Universe. The origin of the central supermassive black holes in galaxies is still a matter of debate — do the galaxies form first and then crush material at their centers into black holes, or do pre-existing black holes gather galaxies around them? Do they evolve together — or could the answer be something else entirely?
“There is something about the Himalayas not possessed by the Alps, something unseen and unknown,” said mountaineer and botanist Frank Smythe…” a mystery intriguing and disturbing. Confronted by them, a man loses his grasp of ordinary things, perceiving himself as immortal, an entity capable of outdistancing all changes, all decay, all life, all death.”
“Our models show that there is a real possibility that Venus could have been habitable and radically different from the Venus we see today,” said Michael Way of The Goddard Institute for Space Science about Earth’s ‘twisted sister’ planet. “This opens up all kinds of implications for exoplanets found in what is called the ‘Venus Zone’, which may in fact host liquid water and temperate climates.”
What would life be like on a planet orbiting a pulsar? Astronomers estimate that the Milky Way galaxy contains an estimated 1 billion neutron stars, of which about 200,000 are pulsars –neutron stars of only 10 to 30 kilometers in diameter with enormous magnetic fields, that accrete matter and regularly burst out large amounts of X-rays and other energetic particles. So far, 3000 pulsars have been studied and only 5 pulsar planets have been found. In 1992, the first exoplanets ever were discovered around pulsar PSR B1257+12.
On Sept. 22, 2017, a ghostly particle ejected from a far distant supermassive black hole zipped down from the sky and through the ice of Antarctica at just below the speed of light, with an energy of some 300 trillion electron volts, nearly 50 times the energy delivered by the Large Hadron Collider at CERN, the biggest particle accelerator on Earth.
Astrophysicists have discovered a dozen black holes —“invisible one-way doors out of our universe” —gathered around Sagittarius A* (Sgr A*), the supermassive black hole in the center of the Milky Way Galaxy, which in May, 2019 suddenly brightened, appearing like a massive, dormant volcano.