[image: 4941.jpg]
*Adophis: God of Chaos and Darkness*
Each day, the Egyptian Sun god Ra traveled through the sky within a great
barge that ascended above the eastern horizon in the morning and then
descended westward just before evening.    After Ra departed the sky, he
traveled through the dark and perilous underworld where his arch nemesis
Adophis dwelt. Depicted as a great serpent, Adophis was the god of chaos
and darkness.   Ra's daily presence in the sky thwarted Adophis' principal
ambition to cast the world into a state of perpetual darkness and tumult.
Consequently, every night he strove to destroy Ra's barge and then consume
Ra so as to prevent the next sunrise.   Ra, having been accustomed to these
nocturnal assaults, deftly repelled his nemesis during each underworld
sojourn. He was aided in these nightly conflicts  both by the coterie of
gods who traveled with him and the human priests who conducted complex
rituals to both empower Ra and weaken Adophis.

[image: Set_speared_Apep.jpg]
Although best known for having slain his brother Osiris, Set also performed
the important role as one of Ra's defenders.   Here we observe him spearing
Adophis during one of Ra's nightly passages through the underworld.

In the very beginning, the god Atum stood on a primordial mound that had
arisen within the center of a chaotic maelstrom.  With the able assistance
of Heka, the personification of magic, Atum created order from chaos and
ushered in the first sunrise. Adophis, then the personification of the
chaos, became so enraged at this new universal order he resolved to destroy
Ra but without success.        The Sun rises still.



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THE DAILY ASTRONOMER
Tuesday, March 30, 2021
Exploratorium XXXV:  Adophis Misses

Location
             99942 Adophis

Time
            December 27, 2004


Be careful!
You're now standing on an asteroid that is approximately as long as the
Empire State Building is tall.   Granted, this little rock serves as a
pleasant walking platform.  (One can even peer over the edge to see the
starfield below.)  However, we assume the severe risk of pushing ourselves
off the surface merely by taking a single step.  Realize that our muscles
are accustomed to counteracting the gravitational pull of the entire planet
Earth.   Here, the surface gravity is a minuscule fraction of Earth's.
 And,

                                       [image: unnamed.png]
*because every action has an equal and opposite reaction*,

the simple act of pressing your foot down would likely propel you upward.
 You'd then lazily move along a parabolic arc above the asteroid for such a
long time you'd likely die of thirst before returning to the surface.   So,
gentle footfalls, folks.

We're here on the asteroid 99942 Adophis on December 27, 2004 because this
tumbling space mountain has made history today.         Today (12/27/04).
Adophis earned a 4 on the *Torino Scale.*

Named after Turin (Itay), the location where the previous scale known as
the "Near-Earth Object Hazard Index" was revised in 1999, the Torino Scale
assigns numbers to outer space objects in accordance to the danger they
pose to our planet.  For instance, an object with a 0 rating has either no
chance or collision or such a small chance that the probability approaches
zero.    This rating also applies to the innumerable micrometeorites that
descend through Earth's skies.  While these little motes do strike the
planet, they won't collide with its surface.   A 1 rating -which isn't much
different- refers to an asteroid predicted to make a close pass to Earth
without posing any risk of impact.

 The ratings 2 - 4 are grouped together under the heading, "Merits
attention by astronomers."     A 4-rating, the highest yet assigned to any
asteroid, refers to a 1% or greater chance of a collision capable of
causing regional devastation.    Attention by officials may be warranted if
the predicted collision is approximately one decade in the future.

On December 27, 2004, 99974 Adophis earned a 4 rating!   Around that time
astronomers predicted that it had a 2.7% percent chance of hitting Earth on
April 13, 2029.   For this reason, we've decided to be here on December 27,
2004, when this became the most famous asteroid: the one many feared would
bring devastation to Earth!   Alas, much to the relief of everyone except,
perhaps, for procrastinating tax filers,  subsequent observations
determined that a 2029 impact was not going to ccur.   Some astronomers
believed it was possible that Adophis would strike Earth on April 13, 2036
if Adophis happened to pass through a strange little space known as a
*gravitational
keyhole*.

                           [image: istockphoto-1183644245-170667a.jpg]
 A gravitational keyhole is a small region in space where a planet's
gravity could alter a passing object's trajectory so as to make a future
impact much more likely or even certain.  Earth is surrounded by many such
little keyholes, some of which are less than a mile in diameter.

Adophis did not venture anywhere close to this keyhole and so a 2036 impact
is also highly unlikely.        In March 2021, astronomers operating the
Goldstone Deep Space Communications Complex refined the orbital
calculations of Adophis and concluded that the asteroid will not pose a
threat to Earth for at least the next 100 years.     Adophis now rates a 0
on the Torino scale and, consequently, will lapse back into obscurity: just
another member of the vast community of known asteroids.

Although the improbability of an imminent collision might make us
complacent, we shouldn't forget that Earth moves  rapidly through a
veritable shooting gallery of asteroids.   On average an Adophis-sized
asteroid strikes Earth about once every 80,000 years. Smaller asteroid
collisions are even more frequent, though admittedly still not common.
Hopefully, by the time astronomers discover an asteroid that will hit
Earth, humans will be able to avert the collision.

We'll wait and see....






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