WASHINGTON - THE main chemical in marijuana appears to aid in the destruction of brain cancer cells, offering hope for future anti-cancer therapies, researchers in Spain wrote in a study released on Thursday.

The authors from the Complutense University in Madrid, working with scientists from other universities, found that the active component of marijuana, tetrahydrocannabinol (THC), causes cancer cells to undergo a process called autophagy - the breakdown that occurs when the cell essentially self-digests.

DARMSTADT (Germany) - THE European Space Agency (ESA) hopes to start monitoring orbital debris within the next few years, an official said on Thursday at the close of the largest-ever conference on a worsening space peril.

'The goal is to be able to offer 'precursor' services in the next two or three years which among other things issue alerts about collision risks,' said Nicolas Bobrinsky of ESA's European Space Operations Centre.

TAIPEI - TAIWAN and China will cooperate on research in Antarctica for the first time, scientists said on Thursday, in a further sign of closer ties between the two rivals.