Examining Nasa's new evidence for Martian life

检查美国宇航局关于火星生命的新证据

Science In Action

科学

2024-08-02

29 分钟
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Nasa's Perseverance Rover has found a fascinating rock on Mars that may indicate it hosted microbial life billions of years ago. Abigail Allwood, exobiologist at Nasa’s Jet Propulsion Lab, is on the team scrutinising the new Martian data. And a couple of newly discovered, approximately 500 year old fossils from the ‘Cambrian explosion’ of complexity caught presenter Roland Pease’s eye this week. First Martin Smith from Durham University tells us about a tiny grub that is ancestor to worms, insects, spiders and crustaceans. Then Ma Xiaoya, who has positions at both Yunnan University in China and Exeter University in the UK, tells us about a spiny slug that was also discovered in a famous fossil site in China. And the first sightings of the landscapes on the underside of the ice shelves that fringe Antarctica. These float atop the ocean around the frozen continent but effectively hold back the glaciers and ice sheets on the vast landmass. Their physical condition therefore is pretty critical in this warming world, Anna Wåhlin of Gothenburg University tells us. Presenter: Roland Pease Producer: Jonathan Blackwell Production co-ordinator: Jana Bennett-Holesworth (Photo: Nasa’s Perseverance Mars rover taking a selfie on Mars. Credit: Nasa/JPL-Caltech/MSSS)

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  • I'm Rory Stewart and I want to talk about ignorance.

  • I will die without having read everything that was written in classical Latin, because.

  • Ignorance isn't simply the opposite of knowledge, it's part of what it means to be human.

  • Just about every game I can think of involves ignorance.

  • There's no adventure without ignorance.

  • There's no narrative.

  • The long history of ignorance from Confucius to QAnon.

  • With me, Rory Stewart.

  • Listen on BBC Sounds welcome to science.

  • In action from the BBC World Service.

  • With me, Ronan Pease.

  • And we're in search of hard to find ancient life this week, spiny slugs from half a billion years ago dug up on a building site in China.

  • A worm the size of a poppy seed, also from China, also from half a billion years ago, preserved in 3d perfume.

  • Normally with a fossil like this, you're just getting a cast essentially of the outer surface.

  • But here we've got this absolutely exquisite detail internally with sort of this micrometer resolution and we can see absolutely everything further afield.

  • Tantalizing clues from Jezero crater on Mars, the kind of geochemical oddities NASA went to find in its quest for 4 billion year old life there.

  • That's in a moment.

  • Also the upside down landscape researchers have found under the ice shelves surrounding Antarctica.

  • Like Grand Canyon.

  • If you imagine we found Grand Canyon in the ice like an ice scape.