FORT COLLINS, Colo. -- A 6-year-old boy is floating over northeastern Colorado in a homebuilt balloon and authorities are racing to try and rescue him.The balloon, in the shape of a flying saucer is covered in foil and filled with helium. It has a compartment for a passenger underneath. It lifted the boy into the air near Fort Collins Thursday morning after the balloon became untethered at the boy's home.The father and son had apparently been working on the aircraft for some time. Fort Collins police and other authorities have been alerted and Airtracker 7 has launched in an effort to locate the boy.Airtracker 7 located the craft at 12:35 p.m. at about 8,000 feet in Weld County. It appeared to be slightly tilted.Skies in the area are partly cloudy and southwest wind speeds are 15 to 20 miles per hour."It is believed the device could rise to 10,000 feet," said Eloise Campanella, Larimer County Sheriff's Officer spokeswoman.Deputies from Larimer and Weld counties are tracking the balloon as it drifts.