Winter solstice one must be able to observe a change in azimuth or elevation less than or equal to about 1/60 of the angular diameter of the sun. Observing that it occurred within a two-day period is easier, requiring an observation precision of only about 1/16 of the angular diameter of the sun. Thus, many observations are of the day of the solstice rather than the instant. This is often done by observing the sunrise and sunset or using an astronomically aligned instrument that allows a ray of light to be cast on a certain point around that time. Length of day
Dump months saturated with high-profile domestic films, much as China itself informally excludes foreign-made films from the summer months. In February 2018 the Spring Festival period set new box office records for China. It had its highest-grossing week ever, at (US$890 billion); its highest single-day gross (US$200 million), and its highest attendance ever, with 30 million going to theaters at some point during the week in mid-month. "Monster Hunt 2" set the country's opening weekend record with receipts of (US$86 million). Dump months The dump months are what the film community calls the two periods of the year when there are lowered