Multicoloured Meteors
If the meteor burns up with many different bright colours, there is a good chance that it is space junk. Colours are caused as the metals burn up, and obviously space junk is made from many different metals .
Some meteors (being rock and dust particles) may burn with different colours depending on their composition (mainly iron and nickel) however they are generally more uniform in colour...
The wake or trail behind a meteor, however, is most frequently green as that is caused by ionized oxygen in the atmosphere as the meteor burns up.