This post discusses the use of latitude and longitude for mapping locations on the Moon and other celestial bodies in the Solar System. It explains how these coordinates are defined, the arbitrary selection of prime meridians, and variations across different planets, emphasizing the importance of consistent astronomical conventions for navigation and mapping.
Tag: Solar system
Gliese 710: The Closest Future Star Encounter
Updated 21 November 2025 In this post I’ll talk about the star Gliese 710. In 1.3 million years’ time it is forecast to pass within 0.166 light years of the Solar System, 25 times closer than Proxima Centauri which is our current nearest star (excluding the Sun of course). The close approach of Gliese 710… Continue reading Gliese 710: The Closest Future Star Encounter
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 Future of the Sun
The Sun, central to our Solar System, generates energy through nuclear fusion, combining hydrogen into helium. Over billions of years, it will evolve into a red giant, ultimately shedding outer layers to form a planetary nebula and becoming a white dwarf. Life on Earth will become uninhabitable well before these changes occur.
Dark Matter
Revised and re-written 11 December 2025 This post about dark matter and is part of my series on cosmology, the study of the origin and evolution of the Universe as a whole. As readers of Dark Energy in the Universe will recall, dark matter makes up about 27% per cent of the mass of the Universe. Evidence for… Continue reading Dark Matter
Explaining Science 