Protecting astronauts from cosmic radiation is one of the key challenges facing future missions to Mars, and Nasa believes it may have a solution.

The space agency, which is planning to send explorers to the red planet in the 2030s, is considering the use of drugs that alter the DNA code of its crews.

This could repair any damage sustained from the high energy particles that will bombard the bodies of 'Marsonauts', giving rise to greater risks of cancer and other diseases.

Nasa's acting chief technologist, Dr Douglas Terrier, made the comments ahead of an appearance at the Codex innovation summit, held in London.

One of the techniques currently under development that it is following is NMN, a compound expected to enter clinical trials after it was shown to rejuvenate elderly mice in laboratory tests.