The European Space Agency has a Planetary Defense Directorate, which includes the Near Earth Object Coordination Center. “We have noticed a recent trend among journalists to come up with creative comparisons to convey the size of asteroids to the public,” they wrote in the April issue of their monthly newsletter.
So, as RockDoctor (Slashdot reader #15,477) explained, “They're proposing a number of standardized units of comparison for journalists to describe Death in the Sky.”
Excerpt from the April 1 newsletter:
In the absence of convenient skyscrapers, animals such as giraffes, corgis, and entire penguin colonies have been commonly used. But how do these comparisons stack up? Let's take a look at some of our favorite unusual suspects:
– Corgi: At about 30 cm tall, a space rock the size of a Corgi is not much of a threat.
– Half giraffe: An adult giraffe can reach up to 5.5 meters in height, so half a giraffe is approximately 2.75 meters long. Although not as impressive as a full skyscraper, an asteroid of that size could definitely destroy a building or two…
– Elephants: Adult African elephants can reach 7 meters at the shoulder. When 90 elephants stack on top of each other, they form an incredible mountain over 630 meters high, setting off a catastrophic but probably not earth-ending event.
Because housing this animal can cause a lot of confusion, NEOCC recommends the use of standardized giraffe units (SGUs, 1 SGU = 5 penguins) to facilitate comparisons.
RockDoctor shares this additional thought in his first post about the newly proposed standardized units.
“The world may be a turtle to the bottom, but it's a giraffe to the top.”