2020-04-02_Science_Illustrated

SPACE ALIENS

Human secrets travel

through empty space

Astronomers have warned against revealing our

location, but it is already too late. For half a century,

physical messages and radio signals have given

away Earth’s location, raw materials, and population.

Aliens receive

nudie pics

In 1972 and 1973, the two probes

of Pioneer 10 and 11 were

launched to travel out of our Solar

System. If ever discovered by aliens,

they will find two gold-plated

aluminium plaques that include a

drawing of a naked man and woman.

The plaques also indicate the probe’s

path out of the Solar System.

Arrival time:

unknown, as is the destination

The man’s lifted arm shows his fingers,

and a binary number indicates the

woman’s height of 168cm.

Unique symbols

will arrive safely

Nine messages were sent to nine

stars from the Yevpatoria radar in

Ukraine in 1999 and 2003. Each Cosmic

Call message included 23 pages

describing Jupiter’s size as compared to

the Sun, indicating symbolic codes for

the numbers 0-9, and explaining pi,

Pythagoras, and more. The symbols’

designs are fault-tolerant, i.e. the

receiver will be able to recognise each

one even if the voyage might have

disrupted parts of the signal.

Arrival time: 2036-2069

Each Cosmic Call symbols is unique; no

reorientation can confuse it for another.

Gold albums on

space voyage

The probes of Voyager 1 and 2

were launched in 1977, each

carrying a gold record including

pictures and sounds from Earth such as

birdsong, thunder, and heart beats. On

one side of the records, instructions

indicate how to play them, how to

draw images based on the recorded

sounds, and information about the

Solar System’s location based on

neutron stars known as pulsars.

Arrival time:

unknown, as is the destination.

Voyager 1 has no specific destination, but in

40,000 years it will pass by the GI 445 star.

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56 | SCIENCE ILLUSTRATED