Eva Garcia's short fingernails are soiled with dirt, but that's fine with her.

Crouched in an open pit just outside the doors of Carmel Mission, formally known as San Carlos Borromeo del Rio Carmelo, Garcia and her CSU-Monterey Bay classmates are unlocking secrets of an ancient way of life.

On Friday, Garcia and her dig partner Carolyn Enos carefully placed yellowed, decaying bones recaptured from the earth into clear pouches, cataloging their finds as a 15-month unprecedented archeological dig winds down. It's likely the bones were from an animal.

"We've had so many emotional moments here, times where I've wanted to scream out what we've found, be it a tooth, a piece of ceramic, pottery, glass or roof tile that still had the fingerprints of the native Indians who made it," said Garcia, a 59-year-old Salinas resident who is among 57 students who have been part of the excavation led by CSUMB archaeology professor Ruben Mendoza. "Then I'd remember, this is a sacred place," Garcia said.

"What we are doing has reverence to it," she said. "It's learning what people ate, how they lived. It's part of the past."

Professor Mendoza and his students will pack up their screens and other tools in the coming weeks, having completed an exhaustive documentation of the site. It is the first formal excavation of an area of the mission and first documentation of the locations of its original structures.

Mendoza, who also has done similar work at Mission San Juan Bautista, and his students have made some surprising discoveries at the Carmel Mission.

The most dramatic is that the more than 230-year-old Mission was constructed to align with Jacks Peaks to the east so the morning sun during summer solstice on June 22 bears down through the mission's prominent front window. The alignment is said to create a representation of the star of Bethlehem.

The result is an awesome 15 to 30 minute light show that concentrates at the church's front tabernacle then moves strikingly down the tile-covered floor of the church. Mendoza has documented the phenomena with video and photos and has presented his findings to archeological academics, creating a buzz of interest to learn if other missions outside those Mendoza has documented feature similar occurrences.

"The native Esselen worshiped the summer solstice. It was part of a tradition of the ancestors of this site," Mendoza said. "This is a major recognition of native belief system."

Mendoza has uncovered that nine of 21 California missions are aligned to mark solstice and equinox. He believes it was a method by the Franciscan missionaries to meld native customs and beliefs into the church. It could also, he said, be part of a church effort to keep an accurate calendar."

"It notes the influence of the native Indians," said Mendoza, who has been invited by the Mexican government to the state of Queretaro to see if any of the five missions established there by Father Junipero Serra share the solstice or equinox alignment.

Details of the work are available online at www.archeology.csumb.edu/ wireless. Mendoza will lecture at 7 p.m. Thursday at Sesnon House at Cabrillo College in Aptos about the missions and their link to astronomy and solar geometry.