Observer Effect (short story)

Observer Effect was the fourth short story in the Short Trips anthology Short Trips: 2040. It was written by Lance Parkin. It featured the Fourth Doctor and Sarah Jane Smith.

Summary
When the Doctor and Sarah Jane save an astronaut called Chang Hu, they are invited onboard a NASA space station on Pluto. But one of the crew, Barrett, is killed... and the TARDIS travellers are immediately put in the frame. Now, the Doctor must convince Chang Hu of his innocence and uncover the real culprit. But Sarah soon discovers enemies sometimes lie much closer to home...

Characters

 * Fourth Doctor
 * Sarah Jane Smith
 * Chang Hu
 * Barrett
 * Talbot
 * Lendal
 * Warry
 * Duncan

Continuity

 * The Doctor once again tells Sarah that it takes two minutes for radio signals to travel between Earth and Mars. (TV: Pyramids of Mars)