Detect magic

Detect magic is a universal spell that detects spells and magic items within 60 feet.

Effect
You detect magical auras. The amount of information revealed depends on how long you study a particular area or subject:
 * 1st Round: Presence or absence of magical auras.
 * 2nd Round: Number of different magical auras and the strength of the strongest aura.
 * 3rd Round: The strength and location of each aura. If the items or creatures bearing the auras are in line of sight, you can make Spellcraft skill checks to determine the school of magic involved in each. (Make one check per aura; DC 15 + spell level, or 15 + half caster level for a nonspell effect.)

Magical areas, multiple types of magic, or strong local magical emanations may confuse or conceal weaker auras.

Aura Strength
An aura's magical power and strength depend on a spell's functioning spell level or an item's caster level.

If an aura falls into more than one category, detect magic indicates the stronger of the two.

Length Aura Lingers
How long the aura lingers depends on its original strength:

Note: Each round, you can turn to detect things in a new area. The spell can penetrate barriers, but 1 foot of stone, 1 inch of common metal, a thin sheet of lead, or 3 feet of wood or dirt blocks it. Outsiders and elementals are not magical in themselves, but if they are conjured, the conjuration spell registers.