The last time I went to Nehru Planetarium I must have been eight years old. All I remember was the excitement of looking at a ceiling screen — a novelty in my time. The rest was what I made up in my head: a dais that moved, a dome that opened and a night sky that came alive.

Here I was, decades later with my eight-and six-year-old, at Nehru Planetarium. The façade was the same. But inside, the canvas unfurled. Before the show opened, there was time to look at the exhibits: the surface of the Moon, the lonely terrain of the plane of Mars and the exciting cubby rooms where you know exactly how much you weigh on the Sun or any of the planets.