1.   A crescent shape indicates a spacecraft took the picture after it had passed the planet.

2.   Consider the time the spacecraft should take to complete a single orbit of the planet.

3.   No other spacecraft has taken as many pictures of Mars.

4.   Scientists will have to wait a few weeks to see the pictures the spacecraft took.

5.   The slowing means the spacecraft will take longer to tighten its orbit of Mars and reach an optimum altitude for the photos, which had been expected Sunday.