Explanation:
There, that faint dot in the center - that's the largest rock known in our
Solar System.
It is larger than every known
asteroid,
moon, and
comet nucleus.
It is larger than any other local rocky planet.
(Nobody knows for sure what size rocks lie at the cores of Jovian planets, or orbit other stars.)
It used to be the largest rock of any type known
until earlier this year.
The Voyager 1
spacecraft took the above picture of the giant space rock in
1990 from the outer Solar System.
This rock is so large its gravity makes it nearly spherical,
and holds heavy gases near its surface.
Today, this rock starts another orbit around its parent star, for roughly the 5 billionth time,
spinning over 350 times during each trip.
Happy Gregorian Calendar
New Year to all the
human inhabitants of
this rock we call
Earth.
