These are some of my cosmology posts
-
The Impact of Stellar Aberration on Astronomy and the Speed of Light Measurement
Stellar aberration was discovered by James Bradley in 1727. He observed unexpected star position shifts, confirming the heliocentric theory and enabling light speed measurement. Today, it’s explained by Einstein’s theory of relativity. … Continue reading The Impact of Stellar Aberration on Astronomy and the Speed of Light Measurement →
-
Solar energy costs
In a previous post I talked about the advantages of solar electricity compared to other renewable source of electricity. In this post I’ll move away from my normal scientific topics and discuss the costs of small scale solar energy and how it compares with other renewables. Whats is ‘the LCOE’? When comparing the relative costs…
-
Advantages of solar energy
As shown in the graph and table below, most renewable electricity is generated by hydroelectric power. Solar energy lies in third place behind wind. Electricity generated from renewable sources. From Our world in data (2018). The ‘Others’ category includes biofuels (e.g. burning wood, animal and agricultural wastes), geothermal energy and wave/tidal power) Despite only being…
-
Easter – 21 April 2019
In 2019 , for the majority of people 21 April was Easter Sunday, one of the most important dates in the Christian calendar. Although Easter is a is a festival celebrating the resurrection of Jesus Christ from the dead, it is also widely marked by non-Christians in the UK, particularly as there are two very welcome public holidays on…
-
An amazing discovery
For those who missed my post on 1 April 2016 here is a re-blog of the amazing discovery of the first intelligent alien life. —Original post below News is just reaching us of the most amazing astronomical discovery which I am ever likely to experience in my lifetime, one which I never thought I would see. As regular…
-
Solar energy
15 December 2025 This orginal post has been revised and updated. However, a new version is at Opportunities for solar energy In this post I’ll talk about some of the science behind this interesting fact and I’ll also discuss how solar energy is likely to become more important to us in the future. The facts…
-
American crewed spaceflight in 2019
Since the retirement of the Space Shuttle in July 2011, America has been unable to put any astronauts into orbit around the Earth. Instead, it has been in the difficult situation of having to rely on the Russian Soyuz spacecraft to ferry astronauts to and from the International Space Station (ISS). This situation may change…
-
21 January 2019 lunar eclipse
On the night of 20/21 January 2019 there will be a total eclipse of the Moon, which will be viewable from many areas of the world. This will be worth making the effort to see, especially for my readers in the western USA and Canada for whom it will occur at a sociable hour. The…
-
Chinese Moon missions
Like many people, I was very excited to hear the news on 3 January that the Chinese spacecraft, Chang’e 4, had landed as planned in the Von Karman crater on the far side of the Moon. Chang’e 4 in the Von Karman crater. The crater lies in the South Pole-Aitken basin on the far side of…
-
What altitude does space begin?
Virgin Galactic plans to resume spaceflights for wealthy customers at around $600,000 per flight, lasting 2.5 hours with only 5 minutes above 80 km. The definition of the boundary of space varies, with the Karman Line at 100 km supported by the FAI, while the FAA considers it at 80 km.… Continue reading What altitude…
Explaining Science 