Cosmic tour of the
Our planet, despite all the challenges we
face living on it, is an unparalleled abode
for life. Located in the Sun’s so-called
Goldilocks zone, the energy we receive from our host star is
just right. It keeps Earth warm enough that liquid water can
happily exist on the surface, but it’s also weak enough that our
oceans don’t boil away. Then there’s our atmosphere — what a
blessing! This thick (but not oppressive) gaseous envelope not
only provides us with the oxygen we need to breathe, but also
protects us from all but the most formidable stray space rocks.
And let’s not forget our planet’s magnetic field. Generated
deep within Earth’s liquid outer core, which surrounds a solid
inner core, this magnetic shield defends us from the constant
onslaught of high-energy particles spewed out by the Sun as
solar wind.
But impressive as Earth is, life has existed here for billions
of years. And we already know quite a lot about our homeworld (even if there’s still plenty left to discover). So, instead of
looking inward, let’s look out. Let’s take a quick tour of the
other planets our solar system has to offer. Along the way,
we’ll brush up on what we already know — as well as what we
may soon find out.BOTTOM LEFT: Multiple large hurricanes are seen brewing in the Atlantic
Ocean in this composite assembled from images taken by a NASA/NOAA
weather satellite on Sept. 6, 2017. NASA/JOSHUA STEVENSBOTTOM RIGHT: The Expedition 7 crew aboard the International Space Station
captured this stunning view of the Sun setting over the Pacific Ocean in 2003.
NASAEARTH
STATS
Mass: 10.3 septillion pounds
(5.97x10^24 kilograms)
Diameter (equator):
7,930 miles (12,760 kilometers)
Average surface temperature:
59 degrees Fahrenheit
(15 degrees Celsius)
Rotation period (day):
23 hours 56 minutes 4 seconds
Orbital period (year):
365.26 days
Moons: The Moon