The fountain of youth isn’t so far off.

Scientists have discovered a revolutionary molecule that could be crucial to the health and survival of Mars astronauts – and crucial to helping us look young forever.

Our cells have the ability to repair themselves, but that declines with age – and scientists finally discovered why. The breakthrough comes after six years of DNA research from scientists at Harvard Medical School and University of New South Wales. Their findings were published Friday in Science.

Researchers found that DBC1, one of the human body’s most abundant proteins, binds itself to the protein that are in charge of mending damaged cells, screwing up the healing process.

Then the team found a molecule called NAD, which stops DBCI – and other proteins – from getting in the way of cell repair. The older we get, the less NAD+ molecules we have.

In trials, researchers had mice drink water with a NAD+-boosting enzyme. “The cells of the old mice were indistinguishable from the young mice after just one week of treatment,” David Sinclair, lead author of the study, said in a statement. Not to mention the treated mice showed improved kidney function, regrown fur and the ability to run twice as fast as their untreated mouse friends.

NASA has already expressed interest in the miracle drug for their Mars astronauts, since radiation on the red planet almost guarantees they’ll develop cancer. It could also be used to help childhood cancer survivors, 96 percent of whom develop a chronic illness by 45 – a sign of accelerated aging.

“This is the closest we are to a safe and effective anti-aging drug that’s perhaps only three to five years away from being on the market if trials go well,” Sinclair said.

Human trials of the treatment are set to begin within six months.