Last Thursday at 17:51 UT, the SLC 40 launch of SpaceX's Falcon 9 took place to put 53 new Starlink satellites into orbit, at an altitude of about 550 km.
At 19h47 UT the braking maneuver of the second stage of the Falcon 9 could be observed mainly from the east and center part of the Iberian Peninsula, including Calar Alto Observatory.
The Falcon 9 had an speed of 4300 km/h, and what the cameras captured were precisely the hot gases emitted by the propellants of that second phase with the aim of making it lose speed to deorbit.
Below are the videos registered with two of the Calar Alto Observatory external cameras.
First video shows the entire sequence, but accelerated at 4x. Second one is also accelerated at 2x.
Calar Alto (CAHA) fireball detection station, together with the one at the Observatory of Sierra Nevada (IAA-CSIC) and others placed at different locations in Spain, are part of the S.M.A.R.T. project led by Professor José María Madiedo (IAA) to track that kind of objects. Specifically, Calar Alto (CAHA) station and the one at Sierra Nevada (IAA-CSIC) constitute a collaboration agreement between the IAA researcher José María Madiedo and both institutions.