Ez talán a legjobban használható:
To find Comet Ikeya-Zhang, look in the western sky shortly after sunset and locate the planet Mars -- that will be a red point of light about 18 degrees up from the horizon. (An outspread hand at arm's length covers about 15 degrees, so Mars is a bit higher than one hand-span.)

To the right of Mars are two bright stars in a nearly vertical line. The comet is at the same height as Mars, to the right of the two bright stars about as far again as the distance from Mars to the stars. Observers should be able to see the comet's bright, star-like nucleus surrounded by a fuzzy cloud of dust and gas called the coma. The comet's tail streaks points nearly straight up from the horizon.

A másfél magnitudónak mi a forrása?