Distance from the Sun: The semi-major axis of Mars' orbit about the sun is 1.52 Astronomical Units (A.U.) or 142 million miles (228 million km); Distance from the Earth: At the 2003 closest approach, Mars was approximately 35 million miles (56 million kilometers) from Earth.
The planet has a diameter of 4,222 miles (6,794 kilometers) at the equator.
These data are taken from HST proposal 10065 by J. Bell (Cornell U.), M. Wolff (Space Science Institute), A. Lubenow (STScI), and K. Noll (STScI). Additional image processing and analysis support from: K. Noll and A. Lubenow (STScI); M. Hubbard (Cornell U.); R. Morris (NASA/JSC); P. James (U. Toledo); S. Lee (U. Colorado); and T. Clancy, B. Whitney and G. Videen (SSI); and Y. Shkuratov (Kharkov U.).
F410M (B), F502N (V), and F631N (R)
NASA and Lisa Frattare (STScI)