What is Maria Reiche's theory about the Nazca Lines?

Her theory is known as the Astronomical Theory. Maria carefully measured and mapped out many of the Nazca Lines herself, using a ladder and other instruments to painstakingly mark out the exact length and shape of the geoglyphs. She used her map to line up the etchings in line of the rising of the most important stars and planetary events like winter and summer solstices. By studying the collections of stars with images of the animal geoglyphs, Maria found that formations like the spider and monkey resembled star constellations like Orion and Ursa Mayor. She believed that the Nazca lines were an atronomical map.