orbiter will have to endure the interplanetary space for 300 days before Mars capture, which means the Mars orbiter arrived around September 1, 2014.
The close passage of Comet Siding Spring to the planet Mars occurred on October 19, 2014.
Directly after its passage, a huge explosion was detected on Mars.
At the moment of the close passage of comet Siding Spring to the planet, NASA cut off the live feed, but Dr.Fritz Helmut Hemmerich was able to make a video from 1200-meters at Tenerife in the Canary Islands showing comet Siding Spring immediately after its Mars encounter and a huge explosion.
Despite NASA cut the live feed in order to hide what was going on during the passage of the comet last year, the image published on ISRA's website probably gives the answer.
The image can be found on the website of ISRO. The Indian Space Research Organisation (ISRO) is the space agency of the Indian government. It is among the largest government space agencies in the world.
Below, Dr.Fritz Helmut Hemmerich's video of comet Siding Spring post-encounter with Mars and the huge explosion.
Link to ISRO's website including the images: