Hazy spot in my yard? Ghost??? No idea, but a little scared! Even my dog noticed it!?

There was a weird light spot in my yard this morning. It almost looked like a haze. At first I thought it was a beam of light from the sun, but it wasn't in a line or anything...if any shape I would call it more of a glob, not even a foot wide and maybe 3 feet tall. It was hard to focus on. It seemed to keep disintigrating and reappearing really quickly. It's very hard to describe! I was playing with my dog and he noticed when I stopped paying attention to him. He came over to me and then he saw it, too! He crouched down and walked toward it slowly like he was curious. He went to sniff it and as soon as his nose touched the spot where the "haze" (not sure what else to call it) was at, it completely disappeared and my dog ran the other direction. There have been strange happenings at my house before, but nothing huge and nothing I ever really thought much of. And on top of that, no strange things have happened in a while. Please excuse any spelling errors. I'm very tired, but I've been pondering this all day. I just want to put it out there and see if anyone has any advice or answers for me? What could it have been? Could it have been a ghost or a spirit (whichever you prefer). Even my dog noticed it, which actually worries me, because that proves that SOMETHING was there. Any similar stories would be appreciated. I'm a little bit scared now.