13 Nov 2020

Another day. Another comet. At ... 11th and 12th November 2020 ... an image of the Orion Nebula with Comet Atlas in the foreground. It will be at its closest position to the earth on the 14th yet will still be 50,000 miles away. Another harmless visit from the back of beyond. The comet is a round green blob, which is actually its atmosphere. The green colour is due to diatomic carbon, or C2, a compound that glows bright green out in  space.

The earth is also pushing its way through the northern Taurids meteor shower, which has an origin in Comet Encke. Meteors appear to emerge out of the Pleiades, which is again the backdrop to what is happening in front of that star cluster. Encke is famous for its gravel like fallout.

At .... supernovae may have impacted life on earth. A study in the International Journal of Astrobiology hopes to make a connection between supernova events and the release of very large amounts of energy in deep space, and climate on earth. How far do climate scientists travel - or are lots of other scientists from different disciplines, jumping on the bandwagon because of all the loot that is floating around. An interesting read at ... but could they have left the mark of their passage in tree rings. The study homes in on C14, otherwise known as radiocarbon, a carbon isotope with an origin in cosmic rays. Radiocarbon appears to leak into the atmosphere at a steady rate on a year by year basis. However, on occasion a pulse of radiocarbon arrives, causing mayhem with the C14 dating methodology. Spikes of C14 are a fact of life. They are known from 775 and 993AD for example, and another spike is also catalogued in the 13th century AD, but of a lower key. They can occur at any point in time and tree rings are one area in which to catch them out. The study brings into focus their origin. Currently, the consensus view is that they emanate from the Sun as a result of solar flares, or coronal mass ejections. This study wonders if some of them have a more exotic origin. Are supernovas involved?

In the course of the research we learn that C14 levels jumped by 3 per cent 13,000 years ago, at the Younger Dryas boundary. Why would that be? However, the authors have a caveat. This is that supernovas are impossible to date accurately.

At ... the asteroid Psyche, a large object in the asteroid belt, has had its likeness imaged. See the link. Very impressive. It is dense and metallic we are told [iron and nickel].

At ... water on the sunlit surface of the moon, facing away from the earth. The study is at