I got an email update on what can be observed this week.
Jupiter looks like a bright yellow-white star, almost as bright as Mars. Saturn is about 10 moon widths to the left and slightly above, and is much fainter, but still bright enough to see from Cambridge. In general, planets can be distinguished by their lack of twinkling, while stars do twinkle.
Why is that the case that stars twinkle, and planets don't? I am aware of variable stars, but I don't think the email means that, since twinkle usually means much more rapid change than variable stars usually exhibit.
