How the European Space Agency Celebrated April Fool's Day

The European Space Agency has a Planetary Defence Office, which includes its Near-Earth Object Coordination Centre. 'It has come to our attention,' they wrote in the April edition of their monthly newsletter, 'that a recent trend among journalists has been to come up with creative comparisons to convey the size of an asteroid to the public.'

So then, as explained by RockDoctor (Slashdot reader #15,477) 'they propose a number of standardised units of comparison for journalists describing 'death from the skies''.

An excerpt from that April 1 newsletter:
In the absence of a handy skyscraper, animals commonly used have included giraffes, corgis and an entire colony of penguins. But how do these comparisons stack up? Let's look at some of our favourite unusual suspects:
- Corgi: At around 30 cm tall, a space rock the size of a corgi wouldn't pose much of
a threat.
- Half a giraffe: An adult giraffe can reach up to 5.5 metres in height, so half a giraffe
would be about 2.75 metres. While not as impressive as a full skyscraper, an
asteroid that size could certainly destroy a building or two...
- Elephants: An adult African elephant can reach 7 metres at the shoulder. Ninety
elephants stacked on top of each other would form a staggering pile over 630
metres high, creating a devastating but probably not planet-ending event.

As this menagerie of animals can cause a lot of confusion, we at the NEOCC
recommend the use of a Standardised Giraffe Unit (SGU, 1 SGU = 5 penguins) for ease
of comparison.

RockDoctor shares this additional thought in his original submission about the newly proposed standardized unit.

'The world may be turtles all the way down, but it's giraffes all the way up.'

Read more of this story at Slashdot.