This post has now been superseded by a more detailed post Measuring Distances in Cosmology ---------------------------------------------------------------------------------------------- I recently read an article on the popular astronomy website site Universe Today. It stated that ‘…the CMB [cosmic microwave background radiation] is visible at a distance of 13.8 billion light years in all directions from Earth, leading scientists… Continue reading Distances in Cosmology
Category: Cosmology
Dark energy an unexpected finding
I offered recently to write an article for my local astronomy society on the discovery of dark energy. It is an expanded version of the blog post I wrote on the topic last year and, at over 3000 words, it is longer than my usual posts. I thought it would be of interest to many… Continue reading Dark energy an unexpected finding
Surveying the Cosmos – Part II
In a previous post I talked about the Large Synoptic Survey Telescope (LSST), a large telescope being built in Chile which will spend 90% of its time surveying most of the sky a total of 1000 times over a 10 year period (in the remaining 10% it will revisit areas of specific interest). In this… Continue reading Surveying the Cosmos – Part II
The discovery of dark energy
The is a now an expanded and updated version of this post available at: https://explainingscience.org/2020/12/10/dark-energy-an-unexpected-finding/ The Expansion of the Universe Astronomers have known since the late 1920’s that the Universe is expanding. By this we mean that distances between objects which are not bound together by another force, such as gravity, increase over time.… Continue reading The discovery of dark energy
Jim Peebles winner of the Noble Prize 2019
I was interested to hear that Jim Peebles, at the age of 84, has won a half share of the 2019 Noble Prize for physics for theoretical discoveries in physical cosmology. Jim Peebles (1935-) Image from Wikimedia commons In the early 1960s Peebles and his colleague Robert Dicke had predicted the existence of the microwave… Continue reading Jim Peebles winner of the Noble Prize 2019
Explaining Science 