Difference b/w Retrorockets & Vernier thrusters

[sorter]

these two term are different but from photos the two components looks quiet alike..i had done some search but can't grasp ACTUAL difference b/w the two as both are small rocket auxillary nozzles...

by the way I have been able to discover what is in the first photo but can't identify a retro/vernier rocket in the 2nd..help will be appreciated.

Apart from this have you noticed the difference in color of the nuzzle in first photo...metal choice difference I suppose

 

[enigma]

Both retros and verniers are rockets, so they will look generally the same as any other. The difference is what they're designed to do.

Verniers are used for attitude control, so they will generally be low thrust, restartable motors designed to be used throughout a mission. Retros are typically fired once to change an orbit by a large degree.

The nozzles in the picture are likely painted with some sort of ablative material to keep the metal from melting.

 

[sorter]

Retros used for deorbital/orbital insertions..ok thnx got it. But verniers used for altitude control?...ths makes no sense in the presence of large primary nozzles which are to take care about altitude. I thing verniers are for orientation control.

 

[enigma]

Attitude control, not altitude.