The Sky on 21 August 2017 at 10.00pm (New York City (USA, NY))
Easily locate the main stars and planets, and observe that all the sky appears to rotate around the pole star! So, the stars rise and set, and the appearance of the sky changes throughout the night...
How to use outside: print this map, and place it over your head, directing "Northern Horizon" to the north. Compare to the real sky!
Night of 21 to 22 August 2017
Other date or time
Observing locationNew York City (USA, NY), 40.71 °N - 74.01°W
Improve the accuracy:
Why the sky is constantly changing?
- because of the movements of the Earth:
- as the Earth rotates on itself, we see the sky scroll as if we were on a ride: the whole sky seems to turn the hours around a point near the pole star (center of the map). This causes the "rises" and "sets" of the stars. In addition, the stroke of the Earth around the Sun shows us a different portion of the sky depending on the time of year.
- because of the movements of the celestial bodies themselves:
- The Sun, Moon, planets, have a perceptible movement over days (or weeks) to the background of stars. Conversely, stars outside our solar system are so distant that they appear stationary in a human life.
Stelvision sky map: online version vs printed version
- the online map can be adjusted very easily to a specific place; it indicates the planets (and the Moon)
- the Stelvision 365 printed map can be taken anywhere, no network or battery problem. With its well readable format (with the associated small lamp) and impeccable impression is a nice object to consult and to offer! It is adjustable for any date of the year with sufficient precision to identify the stars between 40°N and 55°N in Europe (including UK), North America (including Canada and most of USA) and Asia. The planets are shown on special identification cards inside the brochure for a period of 4 years.