In a University of Colorado dorm, a mechanical planetary system set to perfect scale orbits hangs above students in a common gathering area.

The Andrews Hall "grand orrery" is part art, part magic, say the engineering students who worked on it as an extracurricular project during the 2011-12 academic year.

The system is 9 feet in diameter and set to a predetermined logarithmic scale -- otherwise Pluto's orbit would spit it past the Kittredge pond, off campus and near Baseline Road. And, yes, Pluto was included for sentimental value.

The model will be unveiled at 3 p.m. Monday in a public ceremony at Andrews Hall, which, southeast of the Fiske Planetarium, houses a residential academic program for engineers.

Students will be dressed in either formal attire or space gear. Yvonne Pav, a junior mechanical engineering student who has worked on the project, is toying with the idea of wearing a Star Trek costume.

The system is driven by a set of 20 gears cut out of quarter-inch brass. Built from scratch, it is the culmination of at least 1,000 hours of design and construction.

Eitan Cher, a former honor student who led the team of students in creating the model, will be returning to the Boulder campus for the ceremony. Cher is now at Northwestern University, enrolled as a master's student in the Engineering Design and Innovation program.

Cher said the orrery project was an expression of the students who make up Andrews Hall.


"We're about more than just engineering -- we're a community of artists, musicians, athletes and more," he said.

On Friday afternoon, students were studying, discussing the orrery, singing duets of Disney songs. Students in Andrews Hall have a Friday night tradition of playing basketball with their professor Scot Douglass, director of the Honors Engineering Program and a faculty member in residence at the hall.

In fall 2011, Douglass challenged Cher to oversee a team of engineering students and develop the orrery.

The orrery was designed so that the orbiting speeds of each planet are accurate in relation to one another. But they're also scaled in a way that the motion can be seen by the casual observer. For example, it will take Mercury exactly one hour to orbit the sun. Pluto's orbit will take 43 days.

Other students contributing to the project were Fiona Pigott, Christopher Miller, D. J. Sutton, Casey Casias, Rianne Campbell, Christina Bonfanti, David Rappaport, Alex Demarais and P. J. Russell.

"We were told to throw some engineering at it and have fun with it," said Miller, a junior mechanical engineering student.

He said the orrery will be a part of the legacy at Andrews Hall, and he hopes it gets future students excited about learning and applying their skills.

Adam Norris, an applied math instructor who advised the students, said he was impressed with their hard-work ethic. He knew they logged late hours on the project because he'd see files updated sometimes at 3 or 4 a.m.

Contact Camera Staff Writer Brittany Anas at 303-473-1132 or