This week’s new questions

Why do I see two extra colours beneath the violet when I look at a rainbow? And why do people open their mouths when they put on mascara?

10 August 2022

2GPFM5E Child in green jacket looking at rainbow over an ocean — Cavan Images/Alamy

Why, when I see a rainbow, do I perceive two extra colours (yellowish and greenish) directly beneath violet? Am I seeing UV wavelengths, with my brain interpreting them as those colours?

Carlo Favetta,
Wyong, New South Wales, Australia

Impressed young asian woman talking on phone with girlfriend while putting mascara in front of mirror at home, sharing rumors; Shutterstock ID 1793035801; purchase_order: -; job: -; client: -; other: - — Shutterstock/Prostock-studio

Why do we open our mouths when we put on mascara?
Megan Gill
London, UK

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