Even though it seems like nothing is moving in the Universe around us, everything that we can see is really receding at a staggering rate that is referred to as the Hubble Constant, or H0. And when everything happens right in front of life itself, the JWST is there to record another instant in time and space. This time around, the expansion rate of the Universe. The fact that JWST’s discovery is consistent with the measurements obtained by the Hubble Space Telescope is perhaps the most interesting aspect of the telescope’s success. But here’s the catch.
Despite the potential significance of that, though, scientists are not really enthusiastic about it. The newly acquired evidence demonstrates that the Hubble data do not include any errors, yet we are still at a standstill. To determine the rate at which our Universe is expanding, we must rely on some other method.
With Webb confirming the measurements from Hubble, the Webb measurements provide the strongest evidence yet that systematic errors in Hubble’s Cepheid photometry do not play a significant role in the present Hubble tension, stated Adam Riess, astrophysicist of the Space Telescope Science Institute (STScI) and Johns Hopkins University.
What is the Hubble Tension?
Examining relics that date back to the ancient Universe, such as light that has been left over in the background of cosmic microwaves or acoustic waves that have been frozen in time, is one approach. This method often yields an expansion rate that is somewhere in the neighborhood of 67 kilometers/ second/ megaparsec. The distances to objects whose intrinsic brightness is already known can also be measured. This can be done by looking at things like Type Ia supernovae or Cepheid variable stars. According to this technique, the speed is approximately 73 kilometers/ second for each megaparsec. This disparity, which is referred to as the Hubble tension, exists between the two.
It is necessary to carry out these studies in the near-infrared range in order to see through any dust that may be blocking light that is closer to the optical. JWST is an extremely effective infrared telescope, and any data that it acquires is not subject to the same limits that other data would be. The next time around, JWST could show us something truly extraordinary and provide an answer to the tension riddle. Nevertheless, until that time comes, it seems that the telescope is one of the most effective tools for dealing with space.
