I have heard this story a few times from a distant friend when I lived in Utah not to long ago.
I'm in Canada now.
Her story has never changed when it has been brought twice before to me, thought you might be interested.
The lady mentioned this story to me last month again to me when I mentioned UFOs to her in an email months after hearing a previous show.
She was herding sheep with her husband up ontop of Mt. Nephi near Provo UT back in 1958 or 1959, she will know the exact year and county.
The craft appeared about 1,000' to 1,500' above them at a stand still.
Then it just took off towards California, West, then shot right back to the same spot were she was. She got scared and ran into the tent, waited about 20 minutes, then poked her head out and it was gone.
I think she mentioned the craft made no noise.
Hope this helps, but please email her first to get a more accurate response on that night from her, if she is willing to talk and have this documented.