Updated 20 November 2025 his post covers a brief history of the Universe from the Big Bang until the the present day. This, as I am sure you'll agree, is a pretty big topic so I'll only give a outline of some of the key events and when we believed they happened. This post is… Continue reading The Universe’s History: From Big Bang to Today
Tag: Astronomy
Astronomy Items
Stardust
Last week I was on holiday in London. Â While I was there, I spent an afternoon at the Royal Greenwich Observatory, which is set on top of a hill in East London. It was commissioned in 1675, making it one of the oldest astronomical observatories in the world. Â Sadly, it can no longer function as… Continue reading Stardust
The Universe Past, Present and Future.
The  Universe is all existing matter and space, including all stars, planets, galaxies and the space between them. This post, which is the first in a series about cosmology discusses the origins of the Universe and its ultimate future. (All my posts on this topic can be found at https://explainingscience.org/tag/cosmology/) How large is the Universe ?… Continue reading The Universe Past, Present and Future.
Artefacts From Earth
This is the final post in a series about human efforts to contact extraterrestrials.  Today I want to discuss the objects which have already been sent out into interstellar space in the hope that at some point in the distant future an alien civilisation will retrieve and decipher them. The Pioneer Plaque On 3 March 1972 Pioneer… Continue reading Artefacts From Earth
This is Earth Calling
Sending Messages to be picked up by alien civilisations is called METI (Messaging to Extraterrestial Intelligence) and is an activity which has taken place with increasing frequency over the past few decades. Advocates of METI argue that in addition to searching for extraterrestrial signals we can increase our chances of making contact with aliens by sending messages to stars which… Continue reading This is Earth Calling
Explaining Science 