Details. as.character and is.character are generic: you can write methods to handle specific classes of objects, see InternalMethods. Further, for as.character the default method calls as.vector, so dispatch is first on methods for as.character and then for methods for as.vector.
But this is the number of stars we can see from the entire Earth and we should remember that one hemisphere of Earth is always in daylight, so really only about 2500 to 5000 stars are visible at night from any given point on Earth.
Constellations and yearly âskylightsâ. The starchart above shows all the constellations visible from the Northern Hemisphere. While not all these constellations are visible at any given time, the chart serves as a visual representation of what you can see over the course of a year. For more details on what you can see this summer, check out the three views belowâ¦.