SketchUp helped evaluate the speed of the Chelyabinsk phenomenon

Using modeling in SketchUp, we were able to approximately restore the track of the object observed on February 15, 2013 over the South Urals, and relatively accurately estimate its altitude profile and, most importantly, speed. It is obvious that what happened over the South Urals is a threat; its nature depends on the nature of the object: whether it is of natural origin or artificial. This is the main question.
Until fragments of the object are found, speed can help clarify its nature. The average speed of natural celestial bodies (20 km / s according to a study for the National Security Council of 1989), regularly falling into the Earth’s atmosphere, far exceeds the values ​​typical for spacecraft of 8-11 km / s).
To determine the speed, we used a video that appeared in abundance; A collection of links to cameras localized in the geographic space was provided by siberiano - thank you for your help.
At the first stage of the restoration, two videos were selected - one was made in Kamensk-Uralsky (140 km north of Chelyabinsk), the other in Magnitogorsk (240 km to the south-west). They were selected according to the most important condition for 3D modeling - the presence of suitable buildings and structures in the frame. 3D models of buildings and structures
were recreated in SketchUpthat fell into the frames, the position of the cameras was restored with the greatest possible accuracy, and rays were built towards the object at different stages of flight. Models were exported to Google Earth - the flight path was restored using them (in the first rough approximation).
The accuracy of determining the route of the object in this way is low - it’s only clear that it was methyl in Miass, and for some reason the maximum energy release was in Chelyabinsk. But to determine the average speed along the length of the track and the time of the object’s movement can be quite acceptable for the first estimates of accuracy.
The object covered 150 km in 15 s, which gives an average speed of about 10 km / s. So if this is a car, then it is very, very slow, which in itself is noteworthy.
At the same time, the object decreased from about 40 km, where its glow was first noted, to 4.5 km.
Work on modeling is supposed to continue; its main current goal - perhaps accurate restoration of the trajectory and analysis of features - there are also a lot of interesting things there. We will be grateful for the help with the source data - videos and photographs, precisely localized in geographic space. Data from a few more “successful” cameras are awaiting processing.
You can download the current track model of the Chelyabinsk phenomenon in the KMZ format . A brief description is here .