Experts from the U.S. space agency NASA are due to arrive today at the copper mine in Chile, where 33 miners are still trapped underground. The experts will advise the Chilean government on how to support the miners until they are rescued.

The NASA team -- a doctor, a nutritionist, an engineer and a psychologist - have a wealth of experience of space missions. They're used to helping astronauts cope with extreme conditions and months of solitude.

The miners they're here to help are gaining in strength. Later they're due to eat their first hot meal in 26 days. Until now, medics have been giving them high protein drinks and dietary supplements.

New video footage of the men was shown on Chilean state television on Tuesday. They seemed healthier and more cheerful than in previous videos.

The company that owns the mine has asked for forgiveness from the miners' relatives, many of whom have accused it of ignoring safety guidelines. The firm denies the accusations, but described the unfolding drama at the San Jose mine as "a terrible situation".

While the rescuers attempt to drill down to the men, there's also concern for their colleagues up above, who were fortunate enough to escape the rock collapse, but who haven't been able to work for nearly a month.

The company paid their wages until the end of August, but is rumoured to be on the verge of bankruptcy. The government says it's helping the miners to find new jobs.