New Scientist - USA (2022-01-22)

22 January 2022 | New Scientist | 53

The back pages Puzzles

Quick quiz #135

1 What name is given to the process by

which the folds of the cerebral cortex form?

2 What is the driest non-polar

desert in the world?

3 The three forms of locomotion by

terrestrial mammals are digitigrade,

unguligrade and what?

4 What is the smallest, coolest kind

of main sequence star?

5 Goldbach’s conjecture concerns

which type of number?

Answers on page 55

Puzzle

set by Chris Maslanka

#151 Alien fingers

When the aliens landed in my back garden,

my first thought was that they use the same

number system as we do, because there was

a two-digit number written in our Earthly

digits on the side of their spaceship.

But when the aliens emerged from the

ship, I saw that they each had 16 fingers.

I intuited that they therefore used a

hexadecimal (base 16) method of counting.

Their first ten digits, from 0 to 9, work

just like our terrestrial decimal system,

but 10-15 are expressed as A to F,

respectively. After F (our 15) comes

10 (our 16), 11 (our 17) and so on.

What can I say, I am very intuitive.

In hexadecimal, 1E is the same as our

decimal 30 (one 16 and fourteen 1s) and

their 25 is our 37 (two 16s and five 1s).

The number painted on the side of their

ship was therefore written in hexadecimal.

Yet by a remarkable coincidence, it could

be translated into our number system by

simply reversing the order of the digits.

What was the alien number in

Earthly notation?

Solution next week

Cryptic crossword #75 Set by Wingding

Scribble

zone

Answers and

the next quick

crossword

next week

ACROSS

7 Hair the Spanish wrapped in paper (6)

8 Break up real lung lining (6)

9 Plant runs into marsh (4)

10 Abnormal urine? It’s a cause of pain (8)

11 Photography equipment starts to take

recordings in groups of whales (7)

13 Tree by the road – an

unprecedented event (5)

15 Addicts steal heroin from cinema staff (5)

17 Shell of polystyrene found in amniotic

membrane with probe, finally (7)

20 Read lots in a frenzy for inspiration (8)

21 Horse seen in lunar plain? (4)

22 Sequence from women

delights geneticist (6)

23 Interpret poem written at end of year (6)

DOWN

1 / 16 Celestial event makes theorem

worse, surprisingly (6,6)

2 Play up to deer (4)

3 Greek king forgot a 1/16 Down (7)

4 Tropical disease makes

conifer short of carbon (5)

5 Early space missions on extremely

dangerous 1/16 Down (8)

6 To some extent, rising clouds

disrupt 1/16 Down (6)

12 1/16 Down! Disperse! Disperse! (8)

14 Elementary particle clears 1/16 Down (7)

16 See 1 Across

18 1/16 Down described by words of song,

changing one note by a major second (6)

19 Design part of flower (5)

21 Use pepper spray on male expert (4)

Our crosswords are now solvable online

newscientist.com/crosswords