Expanding the Universe

10 Nov 2019

Scientists are expanding the universe it would seem - via state of the art technology and technique. See https://phys.org/news/2019-11-scientists-refine-quickly-universe.html ... what we have is another measurement of the Hubble Constant - recently made uncertain by several studies that have come up with different rates of expansion. The concept of an expanding universe was put forward by Edwin Hubble in the early 20th century. He found that galaxies were moving away from each other - so the story goes. Later, he tried to quantify the rate of expansion, coming up with 500km per second per mega parsec. A mega parsec was deemed equivalent to 3.26 million light years - so, it was very fast. The calculation became known as the Hubble Constant - and subsequently, astronomers have been adjusting it, both upwards and downwards. In the new study the measurement is 67.5 km per second per mega parsec.

At https://phys.org/news/2019-11-nicer-record-setting-x-ray.html ... NASAs NICER telescope on the International Space Station has detected a sudden spike of X-rays - a burst of energy described as as a massive thermo nuclear flash from the surface of a pulsar. As it subsided the flash of light 9described as a fireball) briefly brightened for reasons currently unexplained. The explosion produced as much energy in 20 seconds than the Sun does in 10 days. Pulsar's are described as the compact cores of stars left behind after the stars ran out of fuel - so a bit of a paradox here. These cores are said to explode - without apparently any fuel. See also https://doi.org/10.3847/2041-8213/ab4ae1