This week’s new questions

Could any of the photons that were around me when I played outside as a child decades ago still exist? And why is this snail (pictured) carrying an extra shell on its back?

16 November 2022

Kid with jet pack pretend to be superhero. Child playing in summer. Kid having fun outdoors. Child pilot against summer sky background. Success, leader and winner concept. Imagination, freedom concept; Shutterstock ID 450428614; purchase_order: -; job: -; client: -; other: - — Shutterstock/Sunny studio

Could any of the photons that were around me when I played outside as a child decades ago still exist, travelling through space?

John Howes

Cardiff, UK

New Scientist. Science news and long reads from expert journalists, covering developments in science, technology, health and the environment on the website and the magazine. — John Davies

I found a snail (pictured) in my garden carrying an extra shell on its back. How common is this and what is its purpose?

John Davies

Welwyn Garden City, Hertfordshire, UK

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