Resolving The Hubble Tension - Astrobites Insight From The Oldest Objects In The Universe

Credit: astronomy.com

One of the most important concepts that has shaped our current understanding of astronomy is the expansion of the universe. Einstein showed through his theory of General Relativity that space is “stretchy,” and that the basic state of the universe on large scales is one of expansion, contraction, or perfect balance. Then, with the help of previous work done by Henrietta Leavitt, Edwin Hubble measured the distances of 46 relatively local galaxies and combined these observations with velocity (redshift) measurements from the literature, like in Figure 1 below. Not only did this work demonstrate the existence of galaxies outside the Milky Way for the first time, it showed that these galaxies were racing away from us, and ultimately, that the universe itself was expanding.Read more

Credit: lab-initio.com