New Scientist - 29.02.2020

52 | New Scientist | 29 February 2020

The back pages Puzzles

Quick crossword #52 Set by Richard Smyth Quick quiz #40 Puzzle set by Hugh Hunt

#48 Seeing red

The traffic lights near me are annoying:

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IRUbVHFRQGV,JRWKURXJKWKHPRQO\

RQJUHHQRQP\ELNHHYHU\GD\DQG,ILUVW

VHHWKHOLJKWVDV,DSSURDFKDURXQGDEHQG

ZKHQ,DPbVHFRQGVDZD\,JHWXSVHW

LI,PLVVDJUHHQOLJKWWKDW,FRXOGKDYHJRW

WKURXJK,FDQVSHHGXSE\DERXWbSHU

FHQWRU,FDQVORZGRZQ:KDWVKRXOGP\

VWUDWHJ\EHLIWKHOLJKWVDUHJUHHQZKHQ,

ILUVWVHHWKHP"$QGZKDWLIWKH\DUHUHG"

$QGKRZRIWHQPLJKW,JHWXSVHW"

Answer next week

#47 Geometra’s tomb

Solution

We are told that when Lees turns left

(at position p) the distance to B (pB) is

100 kilometres further than the distance

to C (pC, let’s call it “L”). So pq = L.

Looking at the diagram, by symmetry Cp and

Cq are the same, so the distance Cq is also L,

so pqC is an equilateral triangle. So the angle

by which Lees turns left is 60 degrees.

1 A sidereal year is the time

Earth takes to orbit the sun

with respect to the stars, and

a solar year is the time the

sun takes to reach the same

point in its annual cycle as

seen from Earth. Which is

currently longer?

 What name is given to the

phenomenon that causes

this difference?

3 In England, which of these

years had no 29 February:

1600, 1700, 1800,

1900, 2000?

4 Leap seconds are added to

compensate for the drift of

astronomical time from time

marked out by atomic clocks.

How many have been added

since the first in 1972?

 Atomic time is defined by

what tiny sort of leap that in

common parlance has come

to mean a very big one?

Answers below

Cryptic

Crossword #25

Answers

ACROSS 7 Yemeni, 8 Plover,

9 Deli, 10 Epidemic,

11 Y-fronts, 13 Elder,

 Canto, 17 Topsoil,

 Sturgeon,  Line,

 Covert,  Dengue

'2:1 Meme,  Merino,

3 Pipette, 4 Optic,  Boreal,

6 Beriberi,  Fraction,

14 Tornado, 16 Turkey,

18 Splint, 19 Delta,  Noun

Quick quiz #40

Answers

Sidereal, by about 20 minutes 1

Precession of the equinoxes

1800 and 1900. The 3

Gregorian calendar includes

a leap year at turns of century

divisible by 400; but England

only adopted this in 1752

274

A quantum leap: specifically, 

the oscillation between energy

levels of caesium-133 atoms









  



 



 



 

 

ACROSS

1 Ovoid bacterium (6)

5 Binary compound of

a pnictogen (8)

9 City on which Fat Man

was dropped on 9 August,

1945 (8)

10 Bone of the lower leg (6)

11 Meteor (8,4)

13 Soft clay mineral (4)

14 Experimental weapons

using Tadarida

brasiliensis (3,5)

17 Able to do more work given

more resources (8)

18 Ladies’ fingers (4)

20 Late 1970s sci-fi

thriller (9,3)

23 Two-terminal electronic

components (6)

24 Process leading to low

blood pH (8)

25 0.5 and 3.14, for

example (8)

26 Palpebra (6)

Answers and the next cryptic crossword next week.

DOWN

 Egg-shaped figure (4)

3 Of mechanics, not

quantum (9)

4 Umbra (6)

 Artificially generated

bodily tissue (9,6)

6  Į

7 Andrew Blum book on

internet infrastructure (5)

8 Roller with coin-shaped

spots on its wings (10)

 Carbohydrate (10)

 Result of O 3 depletion (5,4)

16 First point of a

coordinate (8)

19 Trig function (6)

 Spokes (5)

 Bird in the genus Apteryx (4)

Our crosswords are

now solvable online

Available at

newscientist.com/crosswords

100

100

L

L

L

q

p

BC

N