ghoti asked me to write about the public open evenings at Cambridge's Institute of Astronomy, which Judith and I have been going to since last year; they run during the winter in order that it's possible to observe the night sky without having to run ridiculously late.

Judith has been getting a lot out of these and particularly enjoys getting a chance to look through the big telescopes (one of which almost discovered Neptune - the then director of the Cambridge Observatory had observed Neptune prior to its actual discovery from the Berlin Observatory, but lacked an up-to-date star map and so didn't recognise it as a planet). The talks beforehand are generally well worth the time: recent ones have included an update on the Rosetta mission, an outline of dark matter and dark energy, and a talk on the large-scale effects of black holes. More often than not, cloud cover is such that we don't in fact get a chance to observe, so they put on extra talks instead from the Cambridge Astronomical Association (an amateur group); these are a bit more variable, some quite silly but for instance we've had CAA talks on volcanic activity on other bodies in the solar system (e.g. Enceladus) and on heavy water's origin in big bang nucleogenesis and the attempts to determine whether Earth's water originates from comets or asteroids.

A good part of the talks still go over Judith's head to some extent, since they aren't explicitly aimed at children. So, for instance, I found the recent talk on black holes to be fascinating: UCLA are doing amazing things using adaptive optics to observe our galactic centre, and apparently there's a correlation between some properties of galactic bulges and the masses of the black holes at their centres which suggests that the mass of the central black hole may limit the size of the galaxy; but I don't think Judith followed very much of it despite listening patiently. On the other hand, she came away from the "What is a (modern) astronomer?" talk and, unprompted, told ghoti about the astronomer who was sitting under an apple tree when he realised that the moon was always falling but always fell past the earth (a much more useful version of the story of the discovery of gravity than you usually hear, I think!). So I definitely think it's worth taking her and I'll continue to do so as long as it's practical.

ghoti got me a lovely lovely telescope for Christmas, so with any luck we'll be able to get some decent observation done at home too. I've been getting a little better at recognising features of at least the winter night sky, and it's a lot more interesting with a telescope.

This post is part of my December days series. Please prompt me!

We started Judith on solids yesterday: a little earlier than recommended, but she was HUNGRY ALL THE TIME. We gave up on the high chair fairly quickly as she was having trouble staying upright in it, and getting rather upset. Two spoonfuls (by which I mean "little bit on the end of a spoon") of apple sauce later, she fell asleep. Eating is clearly hard work.

After finishing the first feed, I'm not entirely sure how much apple sauce was inside her and how much was on the bib, but there was certainly lots of the latter. She gave an enormous burp and then managed to grab a clean bit of her bib and wipe her face with it. We were very impressed.

Today she ate about three or four teaspoonfuls of apple sauce; the guidelines for how much you should expect your baby to want when starting them on solids say about one teaspoonful. Hardly any of it went on her bib, compared with yesterday.

I don't think we're going to have problems getting this one to eat for a while!