The family of missing California teenager Trinity Backus says she left home in her pajamas without shoes on Thursday, and they have not heard from her since.

The Nevada County Sheriff's Office said in a Thursday Facebook post that the 16-year-old left a residence on the 18000 block of Kentucky Ravine Road in Nevada City, California, around 10:30 p.m. PT. 

She was last seen wearing pajamas and a maroon robe.

Ashley Bjorklund, Backus' aunt, said the 16-year-old "had no shoes on" and "was wearing socks pajama pants and a thin flannel [sic]" in a Thursday Facebook post.

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Backus is described as 5 feet, 9 inches tall, weighing about 130 pounds. She has red hair and green eyes.

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The sheriff's office has received help from a number of local law enforcement offices, as well as the Nevada County Sheriff's Search & Rescue, in its search for Backus. 

On Thursday night, law enforcement officials deployed an airplane with infrared capabilities to conduct an aerial search for the teenager.

Authorities are asking anyone with information about her disappearance to contact 911 or the Nevada County Sheriff's non-emergency dispatch center at 530-265-7880.