I live in a 2 story house on a hilltop and the rear of the house has a lot of glass windows. The view goes to the horizon and with a 90 degree scope. Perth has daylight saving, so it was quite light and bright at the time with no cloud and the sun was behind the house. I was watching TV and a bright, travelling light in the sky caught my eye outside at exactly 17:00 +9GMT. It was worth investigating so I quickly jumped up to the window to get a better view. Looking in an easterly direction at approximately 25 degree elevation, I could see an object flying at an extremely fast pace in a northerly direction. (I can see Perth airport and Jandakot airport traffic as a common occurrence in this same view-point and the speed was easily 30-50 times faster). The object travelled in the northerly direction to then stop for about 2 seconds and sharply turn away (south easterly for 2 seconds) and disappear from view after changing to an easterly direction (directly away from me). I have seen thousands of aircraft fly in this area and no aircraft has either travelled or changed direction that fast.The object appeared to be polished metal like composition as it reflected the light so well with no noticeable self illumination. The whole event took around 10 seconds.Questions not yet answered:3. What did you think the object was when you first noticed it? Holy Moly, that is absolutely moving and cannot be a normal aircraft. When it stopped (not turn as in an ark), it thought "how can it stop that fast". When it veered back and then change direction, I thought "That isnï¿½ï¿½ï¿½t from here!"5. Describe your feelings, reactions and actions, during and after sighting the object. I felt in absolute awe of something that can move like that with an emphasis on G-force and acceleration.