Ms Ashby told The Advertiser she was sure the disc of light floating above her home in Hazelwood Grove, Sanderstead, had extraterrestrial origins.
She claimed: "I don't know what else it could be – although I didn't notice it at the time."
"A friend of mine has a sunset on his monitor that is quite beautiful and I wanted something similar.
"So one morning I got up early to take a picture of the sunrise outside my window because the view is pretty"
Impressed by the view from her window Ms Ashby took the photo on her camera phone on Wednesday, November 20, and thought little else of it.
She explained: "I didn't look at the picture very closely after I took it until the weekend.
"I met up with the same friend and, after looking at the photo, he said "what's that dot in the corner?" and pointed to a small speck on the screen."
Because it was stored on her camera Ms Ashby had not noticed the disc shaped object hovering in the right hand corner of the image.
She exclaimed: "We zoomed in on it and he said "That's a UFO."
"It's quite exciting. I really do think that's what it looks like. There is nothing else it could be – it's definitely not a plane."
Because Ms Ashby took the snap at 7am, she says there's no chance the object is the reflection of a light bulb – because she hadn't yet switched one on.
She is ready to believe that she had unwittingly snapped a visitor from another planet.
"I've never given it much thought before now," she explained.
"But I've always been a believer that there are things that human kind cannot explain."
Since her chance find Ms Ashby says she has been inundated with requests for a copy of her unusual snap.
"My friends who have all wanted copies of it – they all want to know what is was," she explained."
Ms Ashby isn't the first person in Croydon to claim to have taken a picture an alien spaceship.
In August experts called for a public inquiry after snapper Sid O'Driscoll photographed what he believed to be a UFO above Purley Cross Tesco.
Then a week later a quiet evening-in turned to shock for Carrie Negri, 23, when she glanced out of her kitchen window in Chichester Road, East Croydon, on Saturday.
She said: "It sounds crazy but I saw seven bright orange missile-shaped lights which seemed to be travelling slowly in formation across the sky.