Category: astronomy

Please try  opeming this blog post again. Something went wrong. “Read more” led to the wrong place, and I don’t yet  understand why or how to cure it.

The Leonid meteors may roar – or may give a sleepy growl – in the night between November 17 and 18 Here is the scene as the radiant – the point or small area in constellation Leo from which the meteors appear to fly out to any part of the sky – climbs into view around midnight.

See the end note about enlarging illustrations.

The ZHR or zenithal hourly rate – the average number an observer might count in a clear dark sky with the radiant overhead – is given for the Leonids as 10. Pretty low, so in some years you don’t notice any. But in a few years Earth has passed through a clump in this stream so dense as to yield the most fantastic meteor storms in history – thousands per second! So it’s worth taking a look, just in case.

Postscript on hallucinations

The Cambridge Dictionary has chosen “hallucinate” as the word of the year. Not because they’ve read my recent description of hallucinations, which began in a Cambridge hospital, but because the buzz topic of the year is artificial intelligence, and some commentators have used “hallucinations” metaphorically to describe statements that are produced by artificial intelligence and are untrue.

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This weblog maintains its right to be about astronomy or anything under the sun.

ILLUSTRATIONS in these posts are made with precision but have to be inserted in another format.  You may be able to enlarge them on your monitor.  One way: right-click, and choose “View image” or “Open image in new tab”, then enlarge.  Or choose “Copy image”, then put it on your desktop, then open it.  On an iPad or phone, use the finger gesture that enlarges (spreading with two fingers, or tapping and dragging with three fingers).  Other methods have been suggested, such as dragging the image to the desktop and opening it in other ways.

Sometimes I make improvements or corrections to a post after publishing  it.  If you click on the title, rather than on ‘Read more’, I think you are sure to see the latest version.  Or you can click ‘Refresh’ to get the latest version.