How fast sunset

This speed diminishes as one leaves the equator and approaches the poles as the distance around the earth diminishes. At the poles a person would only need to stand still but rotating to experience 24 hours of sunset on equinox days. Speeds would vary on other days of the year due to the earth's tilt.

Brad Elliott, North Rocks. The earth has a circumference of about 40, kilometres and rotates once every 24 hours. To make it easier on yourself, you could move either north or south and travel around a latitude of lesser circumference. Jake Downs, North Narrabeen. It depends where you are. If you are on the equator during an equinox kmh should do it the circumference of the earth divided by Go to either pole in mid-summer and you need only to stand still.

Peter Kenny, Bexley. About the same speed as you'd need to travel and look backwards to see a constant sunrise but it would be more fun because happy hour beats soggy Weet-Bix any time. Really, it all depends on where you are. The radius of the earth varies but kilometres is a good average. So, for flying round the world on the latitude of Sydney, the required speed is about kmh. David M. Calvey, Vaucluse. First, it depends on your definition of perpetual. If, instead of infinity, you mean a set period, say 24 hours, it would depend on your geographical latitude at your starting point.

Then the speed would be the circumference of the Earth at that latitude in 24 hours. Alice Hofler, Dee Why. How is the quantity of pollutants released into the atmosphere measured and how reliable are the quoted figures? Scientific and other reports are as reliable as the biases of the members of the committee responsible and as guaranteed as the intentions of the politician who commissions them.

Barrie Brown, Gordon. The three main methods used to measure the pollutants in the atmosphere are: passive sampling, active sampling and automatic sampling, which is the most precise and expensive. Using this technique, pollutants are continually collected and analysed at least every hour.

The accuracy achieved enables pollution episodes to be analysed in detail and related to traffic flows, meteorology and other variables. John Moir, Mollymook. We set off from Reykjavik in Iceland, and continuously kept up with the sunset for eight hours before landing in our final destination in the Arctic Circle.

The intense calculations required to get it right and the harsh arctic conditions also complicated matters. Space in the aircraft was also a challenge; when you have four people inside such a small airplane you can imagine how difficult it was to move around the space and shoot different angles. It was also packed, cold, and intense inside. Everyone had a task to do and a small time window to get it done.

But even after all that we got what we needed and achieved our goal and mission. AWS Deloitte Genpact. Events Innovation Festival. This illustrates the geographical effect , which depends on the observer's latitude. Figure 8 and 8a below. The daily path of the Sun as seen from Hawai'i on the first day of spring, summer, fall, and winter. The Sun is above the horizon all day at the beginning of summer, barely touching the horizon at midnight.

At the beginning of winter the Sun's path is entirely below the horizon. This latter situation is modified by the refraction of sunlight by the Earth's atmosphere which causes the Sun to appear a little higher at the horizon than it actually is.