91av

Regulars

Rake with fallen leaves in autumn. Man cleans the autumn park from yellow leaves. Volunteering, cleaning, and ecology concept. Seasonal gardening.; Shutterstock ID 2026442297; purchase_order: -; job: -; client: -; other: -

Life

Why you don’t need to bother raking up dead leaves from your lawn

When the leaves start falling, we can spend hours removing them from our lawns. But leaving them where they are is often better for the grass, says James Wong

Regulars
Sound waves spectrum

As sound dissipates, what happens to this energy?

Regulars
Two seagulls above aircraft wing

Do winged animals ever suffer comparable mishaps to aircraft? Part two

Regulars
In this Voyager 2 image of Saturn, obtained Aug. 11, 1981, from a range of 14.7 million kilometers (9.1 million miles), north is at the upper right edge of the disc. Seen above the planet are the satellites Dione (right) and Enceladus. This false-color print shows a green spot at the south edge of a yellow band; in true color, the spot would appear brown and the band white. A bright yellow spot slightly above and to the left in this image moves eastward relative to the green spot at a rate that allows it to pass the green feature in about 50 days. The convective clouds that appear between the two spots are typical of the region. Here, the smallest visible structures measure about 270 kilometers (170 miles). The Voyager project is managed for NASA by the Jet Propulsion Laboratory, Pasadena, Calif. https://www.jpl.nasa.gov/images/pia01959-voyager-2-image-of-saturn

This week’s new questions

Regulars

Pretend engine noises make electric cars more fun

Regulars

Tom Gauld on some useful new tech terms

Regulars

Twisteddoodles on commonly confused words

Regulars
Quat is an artemia collector. Artemia is a primitive arthropod also known as brine shrimp, it is used as a rapidly growing food source for farm fish. The salinity level of the water in the Aral Sea does not allow any other life to exist in or near it. A tiny creature you can?t see with the naked eye is all the sea is willing to give.

Environment

Picturing life in the dust bowl remains of the once mighty Aral Sea

Regulars
For Maker 2nd Dec

Mathematics

How to perfectly wrap gifts of all shapes and sizes using maths

Regulars
2JP8KPY Very tight parking in Italy with a small dented family car bumper to bumper squashed in next to two cars in a parking bay with only inches to move.

What is the shortest space a parking car can get into?

Our readers have lots of answers for this one, with some invoking Pythagoras and others advocating manually lifting a car into place to ensure the tightest possible fit

Regulars

Why don’t marine mammals like whales get ‘the bends’? Part 2

Regulars

This week’s new questions

Regulars

Killing pigeons ‘not in their best interests’, find pigeon ethicists

Regulars

Tom Gauld: Notice how the eyes follow you around the room

Regulars