I questioned if that dot could even be one of Mars' moons, so I decided to compare sizes and distances...
Here's information about Earth's moon:
Distance Radius Mass
Satellite (000 km) (km) (kg)
--------- -------- ------ -------
Moon 384 1738 7.35e22
http://seds.lpl.arizona.edu/nineplanets/nineplanets/earth.html
Mars' moons:
Distance Radius Mass
Satellite (000 km) (km) (kg) Discoverer Date
--------- -------- ------ ------- ---------- ----
Phobos 9 11 1.08e16 Hall 1877
Deimos 23 6 1.80e15 Hall 1877
http://seds.lpl.arizona.edu/nineplanets/nineplanets/mars.html
These distances are from the center of the planets. So, remember that Mars is smaller than Earth, so the same distance between the center of the planet and an object in space would look like more on Mars than it would on Earth. Mars' moons are also much smaller than Earth's.
Earth's moon is 42.66 times as far away from the center of the planet as Phobos, and is 158 times the size.
Earth's moon is 16.69 times as far away as Deimos, and 289.67 times the size.
I don't know if I did the right thing, but I divided how much farther Earth's moon is by how much bigger Earth's moon is. I got 0.27 for Phobos and 0.058 for Deimos.
So, I take it the moons of Mars would appear much smaller than Earth's from their own planet. Of course, you also must consider that Mars is smaller than Earth, which I didn't (since I'm too lazy), so they will appear even smaller than my calculations, if correct, suggest.
If somebody knows I messed up, please correct me.
I think the dot is much more likely to be something on the camera or something flying in the distance due to the winds, though. :shrug: