NOVA | scienceNOW | Watch Online

Watch the complete July 23, 2008 broadcast of NOVA scienceNOW here. To watch any of our segments from past episodes online, go to past stories.

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Running time: 2:09

	Leeches A century after falling out of favor among doctors, medicinal leeches are back in hospitals, sucking away on patients' wounds. Watch this segment
	The Search for ET Astronomers have their radio telescopes tuned to receive signals from alien worlds, but is anybody out there? Watch this segment
	Stem Cells Breakthrough Three separate teams overcome a biomedical hurdle—creating stem cells without the use of human embryos. Watch this segment
	Profile: Edith Widder Meet a marine biologist and explorer who has engineered new ways to spy on deep-sea creatures. Watch this segment

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Leeches

The Search for ET

Stem Cells Breakthrough

Profile: Edith Widder