The high failure rate of missions launched from Earth attempting to explore Mars has become informally known as the "Mars Curse" or "Martian Curse". The "Galactic Ghoul" or "Great Galactic Ghoul" is a fictional space monster jokingly said to consume Mars probes, a term coined in 1997 by Time Magazine journalist Donald Neff.
Of 38 launches from Earth in an attempt to reach the planet, only 19 succeeded, a success rate of 50%. Twelve of the missions included attempts to land on the surface, but only seven transmitted data after landing.
The majority of the failed missions occurred in the early years of space exploration and were part of the Soviet and later Russian Mars probe program that suffered several technical difficulties, other than the largely successful Venera program for the exploration of Venus.
Modern missions have an improved success rate; however, the challenge, complexity and length of the missions make it inevitable that failures will occur.
The U.S. NASA Mars exploration program has had a somewhat better record of success in Mars exploration, achieving success in 13 out of 20 missions launched (a 65% success rate), and succeeding in six out of seven (an 86% success rate) lander missions.