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Hampstead Observatory has one major advantage over the famous telescope in Greenwich -- it allows the public to just turn up and see the stars for free. You don't even have to book. As long as the skies are clear, the observatory will open up for a few hours at the weekend and allow people to take a peek at the stars.
Don't go there expecting a massive telescope like the one on Greenwich Hill. Hampstead Observatory is a very small observatory with a six-inch refractor, housed inside a rotating dome. But it's more than big enough for beginners and keen amateurs to marvel at the moon, stars and planets.
Astronomers will sometimes bring along their own equipment too, and there are plenty of experts around willing to give beginners some advice.
Note: The observatory will only open if the skies are clear. The Sunday lunchtime opening hours are for people to view the Sun.
If you enjoy astronomy, then you might like to see if there are any events on at the Royal Observatory. Of particular interest will be their daytime planetarium show, which will tell you what is visible in the night sky tonight.