杏吧原创

Last Word

Close-up of delighted senior man twirling moustache and smoothing his grey beard. Man taking care of his bushy beard and mustache ; Shutterstock ID 559674487; purchase_order: -; job: -; client: -; other: -

Why does our hair go white while eyebrows stay their original colour?

Eyebrows and eyelashes do go white if you live long enough, says one reader - but it鈥檚 really a question of how hard your hair follicles are working

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Blue and dark space landscape with planets and starry sky and mountains. Huge planet on the horizon volumetric lighting 3d rendered baackground.; Shutterstock ID 2208373835; purchase_order: -; job: -; client: -; other: -

This week鈥檚 new questions

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grass lawn with yellow daffodils in dutch garden 'Keukenhof', Holland; Shutterstock ID 172603808; purchase_order: -; job: -; client: -; other: -

Why are so many spring flowers yellow?

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The two interacting galaxies making up the pair known as Arp-Madore 608-333 seem to float side by side in this image from the NASA/ESA Hubble Space Telescope. Though they appear serene and unperturbed, the two are subtly warping one another through a mutual gravitational interaction that is disrupting and distorting both galaxies. This drawn-out galactic interaction was captured by Hubble???s Advanced Camera for Surveys. The interacting galaxies in Arp-Madore 608-333 were captured as part of an effort to build up an archive of interesting targets for more detailed future study with Hubble, ground-based telescopes, and the NASA/ESA/CSA James Webb Space Telescope. To build up this archive, astronomers scoured existing astronomical catalogues for a list of targets spread throughout the night sky. By so doing, they hoped to include objects that had already been identified as interesting and that would be easy for Hubble to observe no matter which direction it was pointing. Deciding how to award Hubble observing time is a drawn-out, competitive and difficult process, and the observations are allocated so as to use every last second of Hubble time available. However, there is a small but persistent fraction of time ??? around 2???3% ??? that goes unused as Hubble turns to point at new targets. Snapshot programmes, such as the one which captured Arp-Madore 608-333, exist to fill this gap and take advantage of the moments between longer observations. As well as creating beautiful images such as this, these snapshot programs enable astronomers to gather as much data as possible with Hubble. Links Video of A Snapshot of Interacting Galaxies

What would happen to Earth if the Milky Way hit another galaxy?

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Reindeers migrate for a best grazing in the tundra nearby of polar circle in a cold winter day.; Shutterstock ID 605430995; purchase_order: -; job: -; client: -; other: -

This week鈥檚 new questions

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Golden lion tamarin; Shutterstock ID 121264012; purchase_order: -; job: -; client: -; other: -

Why aren鈥檛 humans covered in hair like other primates are?

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2EXM9NK Hand Knuckle Finger Joint Crack. Fingers Snap

How can popped knuckles be so exceptionally loud? Part 2

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PEWCN3 Relaxed senior couple on picnic sitting on park bench talking and having coffee. Old man and woman relaxing at park having coffee.

Why do older people seem to find that time passes more quickly? Part 2

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close up the fly on the window, on the glass, the concept of sanitation, dangerous insects, insect repellent, copy space; Shutterstock ID 1168097506; purchase_order: -; job: -; client: -; other: -

This week鈥檚 new questions

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Kudzu ( Pueraria lobata ) flowers. Fabbaceae perennial vine. Dark blue-purple fragrant butterfly-shaped flowers bloom in racemes from July to September. The roots are edible and medicinal.; Shutterstock ID 2360739029; purchase_order: -; job: -; client: -; other: -

Why do the climbing plants in my garden all twine anticlockwise?

If they twine anticlockwise, these plants are probably bindweed - and good luck getting rid of that, say our readers, many of whom are keen to reference the old Flanders and Swann song about a bindweed and honeysuckle that fell in love

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What is the best way to minimise crumbs when slicing bread?

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This week鈥檚 new questions

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Could Earth sustain life without having been hit by a dwarf planet?

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How did Roman road builders know which way to go? Part 2

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