The sublime beauty and the danger of physics is that sometimes things exist that we can never see. Which led scientists to ask: Was an unknown object, perhaps a cosmic string, weird one-dimensional defects in space-time that should be out there, somewhere, detected at the Milky Way’s galactic center in 2016? If yes, it could have profound implications for understanding gravity, space-time and the universe itself.
“These objects look like gas and behave like stars,” said co-author Andrea Ghez, UCLA’s Lauren B. Leichtman and Arthur E. Levine Professor of Astrophysics and director of the UCLA Galactic Center Group about a new class of bizarre objects with orbits ranging from about 100 to 1,000 years at the center of our galaxy, not far from the supermassive black hole called Sagittarius A* that look compact most of the time and stretch out when their orbits bring them closest to the black hole.
Ten headline stories from Planet Earth, the Milky Way and the Cosmos Beyond…
“Our standard model of cosmology is based on an isotropic universe, one that is the same, statistically, in all directions,” says astrophysicist John Webb at the University of New South Wales about the universal constant which appears inconstant at the outer fringes of the cosmos, it occurs in only one direction. .”That standard model itself is built upon Einstein’s theory of gravity, which itself explicitly assumes constancy of the laws of Nature. If such fundamental principles turn out to be only good approximations, the doors are open to some very exciting, new ideas in physics.”
On April 10, 2019, the Event Horizon Telescope (EHT) team of radio astronomers produced the first photograph of the M87 Galaxy’s black hole the size of our solar system described by astronomers as the “gates of hell and the end of spacetime.” The now iconic image captured light from the entire universe wrapping around the object in a nested series of rings.
Black holes, predicted Einstein, are supposed to have a singularity—a point that is so small and dense that our human brains can’t even comprehend it. But what if some phenomena that look like black holes are actually cosmic objects full of dark energy –an enigmatic phenomena that has been described as everything from a fifth force to a new form of matter, but so far, no direct evidence has been found of its existence. About which Noble-Prize winning physicist Adam Riess says: we have absolutely no clue what dark energy is. Dark energy appears strong enough to push the entire universe – yet its source is unknown, its location is unknown and its physics are highly speculative.
