Awesome Giant UFO Near Earth (March 2014) [video] - Art'einsky

You mind tells you that this is impossible, but it is possible. Such UFOs have been recorded before on radar and yes, on similar scales. Just click here to see a past sightingADGUK News states: Ok, this image was released by the Brasilia Planetarium recently and seems to show a massive disc shaped object stationed above the Earth. The disc is estimated to be around 3-5 thousand miles in diameter. If
you look at the  bottom left of the image you can see a cloud formation passing over the top of the anomaly, this indicates that the object is not a projection onto the earth. I have no idea what this object is, i can only speculate at this point. I have contacted the Planetarium for further clarification regarding the slide, and will post an update when I get an answer. Source: Article