AQUILA Magazine Earth Issue plus resources | Page 4

Our planet is perfectly poised for life , but we can no longer afford to take it for granted . If we want to remain on Earth , we must learn how to balance the delicate systems that keep it all going . In short , we all have some serious work to do .

Earth is a Goldilocks Planet .
Because it sneaks into people ’ s houses without their knowledge ?
No .
Because it has no respect for people ’ s privacy or belongings ?
Again no .
Because it runs away screaming whenever challenged on its horrendous behaviour ?
Wrong again . It ’ s called a Goldilocks Planet because it ’ s in the Goldilocks Zone . That means it ’ s not too hot , it ’ s not too cold . It ’ s juuuuust right for life !
However , simply being inside the Goldilocks Zone is not enough to sustain life . In order to keep all our systems in balance , a planet must also trap the right amount of warmth , and let the right amount go .
Our star ( the Sun ) gives out radiation ( energy ) right across the electromagnetic spectrum , but most of it comes from a very small part . We can see the visible spectrum , but to either side of this is invisible energy : ultraviolet and infrared .
You might have heard of these before – ultraviolet energy is responsible for sunburn ( ouch ) whereas infrared energy is detected by ninjas thermal cameras .
The term Goldilocks Zone describes the area
10 3
1 kilometre
10 0 10 3 1 metre 1 millimetre
10 6
1000 nanometre
10 9
1 nanometre
10 12 metres
around a star ( like our Sun ), where conditions
are right for life as we know it . Planets in this
area might have liquid water ( as well as ice or
water vapour ) because their temperature is in
the right range . They gain enough energy
from their star that any potential life can stay
warm , but it won ’ t get hot enough for it to be
frazzled immediately !
In scientific circles this area is more correctly known as the circumstellar habitable zone ( CHZ ) or simply , the habitable zone . We think there are around 40 million Earth-sized planets like this in the Milky Way alone . ( Mind blown , ed .)
700 nanometres 600 nanometres 500 nanometres 400 nanometres
A curly-tailed dog ( Nova ) in the snow , taken by a ninja with a thermal imaging camera . This technology helps us to see the heat ( infrared ) energy being emitted by the dog against the cold background of the snow .