OT: Amazing telescope and dark energy measurements

This article describes new data about dark energy. The standard model of the universe known as L.C.D.M. is composed of 70 percent dark energy (which we can’t see and only theorize due to the ever-increasing rate of expansion of the universe), 25 percent cold dark matter (an assortment of slow-moving exotic particles that we can’t see since it doesn’t interact with electromagnetic radiation though it has gravity) and 5 percent atomic matter (that is, our normal, familiar matter which we can see and measure directly).

The data was collected by an amazing telescope at Kitt Peak National Observatory with 5,000 fiber-optic detectors that could conduct spectroscopy on that many galaxies simultaneously and find out how fast they were moving away from Earth. The article has an absolutely mesmerizing animation of how the robotically-adjusted fiber optic detectors are constantly moving to keep aligned with their assigned galaxies without bumping into each other.

Bottom line: dark energy MAY change over time. It may not be a constant as currently supposed. At issue is a parameter called w, which is a measure of the density, or vehemence, of the dark energy. Vehemence! Density is a property of ordinary matter so it makes sense to use a different word to describe dark energy.

As a measure of distance, the researchers used bumps in the cosmic distribution of galaxies, known as baryon acoustic oscillations. These bumps were imprinted on the cosmos by sound waves in the hot plasma that filled the universe when it was just 380,000 years old. Back then, the bumps were a half-million light-years across. Now, 13.5 billion years later, the universe has expanded a thousandfold, and the bumps — which are now 500 million light-years across — serve as convenient cosmic measuring sticks.

We truly live in a golden age of cosmology. The data from the space-based telescopes is being combined with data from earth-based telescopes to redefine our understanding of the cosmos.

By the way, the PBS show “Space Time” is absolutely mind blowing. This is real astrophysics, not watered down for the masses.

https://www.pbsspacetime.com/

Wendy

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