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.
The star is 25,000 light-years away from Earth. Despite this great distance, the star would be visible to the naked eye if it were not for all the dust between it and the Earth. UPDATE! As of January 2009, we now know about some other really big stars. One is called Eta Carinae.