# Trudy E. Bell 

1260 Andrews Ave.

Lakewood, OH 44107

216-221-5008

216-221-5088 fax

[t.e.bell@ieee.org]{.underline}

**RED = Rwonderful**

**BLUE = (almost)Boring**

\[text of body: 993 words -- target: 800\]

**A Gift from the Sky**

*Whenever both sun and clouds are in the sky, be sure to* **look
up***\--you may behold rare rings, arcs, and other marvels!*

Shortly after lunch on Wednesday, September 25, 2002, I stepped out onto
the rear deck of my home in Lakewood, Ohio, and glanced up\--and was
arrested by the sight of an extraordinarily bright, rainbow-colored
*football-shaped* halo around the sun.

Knowing that a combination of thin cirrus clouds and bright sunlight is
the prime condition for upper-atmosphere ice-crystal optical displays, I
walked down the drive to my larger front lawn. Yes, the halo\'s **inner
circumference was circular but its outer circumference was
elliptical**\--it was what is known as a **circumscribed halo**,
sometimes seen when the sun is high (in this case, 48 degrees).

Flanking it both left and right, I also saw two brilliant, comet-shaped
rainbow-colored sun dogs or mock suns (technically known as *parhelia*
from Greek words meaning "beside the sun").

Most dramatically, from each sun dog I caught sight of a long,
horizontal, white streak extending away from the halo. Excitedly, I
began turning to see how far the extensions reached\--and made a
complete 360, accidentally unbalancing myself and falling onto the
grass.

\"That\'s *the complete parhelic circle!*\" I exclaimed aloud to the
empty street.

There it silently hung, an enormous white circle suspended in the pale
blue cirrus-cloud-streaked sky at the same altitude as the sun, centered
on the zenith and parallel to the entire horizon. What was more, in both
directions a third of the way along it from the sun were two
unmistakable white mock-sun brightenings\--indeed, I was seeing rare
**120-degree parhelia**. Lastly, there was the faintest suggestion of
yet another mock sun **diametrically opposite to the sun almost due
north\--the so-called anthelion, also rare**!

I raced into my house and grabbed my camera; with shaking hands, I
mounted the 19-mm wide-angle lens and lay back on the front lawn with
lens pointed to the zenith. To my acute disappointment, the parhelic
circle\--while plenty bright enough to photograph\--was far too huge
(nearly 85 degrees across) to fit within the field of view. So I fetched
pencil and pastels and rapidly began sketching \[Fig. 00 PASTEL
DRAWING\].

Just then, my neighbor Cindy backed her van out of her drive. I called
to her and pointed upward.

She stepped out of her idling van and looked up. Her eyes widened and
her jaw dropped. \"Was this predicted?\" she asked eagerly. \"Did people
know this was going to happen? How do you find out when to look?\"

No, I explained, the daytime sky is so subject to local weather that
such atmospheric ice-crystal displays cannot be predicted the way
astronomers can pinpoint the dates and times of meteor showers and
eclipses. Seeing such a breathtaking light show is more analogous to
sighting a rare migratory South American bird in Ohio: knowing generally
the right conditions and time of year, you must trust to luck and
vigilance.

In short, it\'s a gift from the sky\--bestowed upon anyone who thinks
simply to *look up*.

Unlike rainbows, which are produced when sunlight is refracted (bent)
through water droplets, halos and parhelia result from sunlight
reflected from or refracted through facets of millions of hexagonal ice
crystals\--either flat plates or long pencils (examples can be found at
[http://www.sundog.clara.co.uk/halo/crystals.htm]{.underline} and
[http://www.sundog.clara.co.uk/halo/platcol.htm]{.underline} ).

The specific assortment of halos and arcs you see reveals much about the
conditions 3 to 6 miles high in the Earth\'s troposphere, where cirrus
clouds form. For one thing, any display at all means the ice crystals
are at least 0.1 millimeter across and of good optical quality; crystals
too tiny or imperfect can\'t act as prisms (see
[http://www.sundog.clara.co.uk/halo/xtalreal.htm]{.underline} ). Indeed,
if the crystals are of exceptional gem-like quality, their reflected and
refracted sunlight can actually festoon the entire dome of the daytime
sky with exotic halos, loops, arcs, and crosses.

In addition, the sun's altitude determines what paths the refracted rays
can take across the sky and into your eyes. If crystals are all of a
similar size or all drifting horizontally through the air, the display
might be multicolored, whereas if the crystals are of various sizes or
tumbling in high-altitude winds, it\'s likely to be white. Lastly, the
exact angle of the crystals in midair will affect the faces through
which sunlight can enter and exit, some combinations of paths being
rarer than others. With the help of computers, atmospheric physicists
have produced actual catalogues of crystals in different orientations
along with the arcs and halos they can produce.

Because air in the troposphere is almost always below freezing,
ice-crystal displays can be seen year-round (I\'ve seen weak sun dogs
even in July). But truly good displays in the United States are most
common in the fall, winter, and spring when the northern jet stream
descends southward, drawing down Arctic air masses with their
treasure-trove of ice prisms \[INSERT OPTIONAL BOX WITH QUOTE FROM
PEARY\]. **Trudy, this red-highlighted statement is so important it
needs to appear earlier in the story.**

\"And to think,\" Cindy remarked, climbing back into her van, \"I
wouldn\'t have noticed any of this if you hadn\'t gotten me just to
*look up*!\"

After she drove off and I returned to my sketching, I pondered her
questions and comment. Although I\'ve been an avid amateur astronomer
and lover of the nighttime sky since 1965, only in the last five years
or so have I also become a devotee of the daytime sky.

In that half-decade, however, my experience has revealed that even
supposedly rare atmospheric-optics displays are more common than
meteorology books imply.

They\'re also of far greater variety than just rainbows (as magnificent
as those are). Now that I\'ve cultivated the simple habit of *looking
up* a dozen times a day, I\'ve found scarcely a week passes without some
reward\--be it solar halos, sun dogs, crepuscular rays (shafts of
sunbeams and shadows from behind puffy cumulus clouds), circumzenithal
arcs (rainbow-colored \"ice bow\" arc half-encircling the zenith), sun
pillars, or...the complete parhelic circle.

Yes, the daytime sky abounds with unexpected gifts, which can be yours
just for taking a moment\--to *look up!*

OPTIONAL BOX WITH QUOTE FROM PEARY:

Complex ice-crystal displays are especially common in the Arctic and
Antarctic, even being produced by the full moon during the months-long
winter night! Here\'s a description of one seen by Robert Peary on his
last voyage toward the North Pole: "On the evening of November 11
\[1908\], there was a brilliant paraselene *\[sic\]*, two distinct halos
and eight false moons being visible in the southern sky. This phenomenon
is not unusual in the Arctic, and is caused by the frost crystals in the
air. On this particular occasion the inner halo had a false moon at its
zenith, another at its nadir, and one each at the right and left.
Outside was another halo, with four other moons." -- Robert E. Peary,
*The North Pole: Its Discovery in 1909 Under the Auspices of the Peary
Arctic Club*, 1910; Dover Publications, 1986, pp. 175-176.

CAPTION TO DRAWING:

No photograph or drawing adequately conveys the enormous size and beauty
of atmospheric ice crystal displays! That being said, this pastel
drawing made from my pencil sketch of September 25, 2002, gives an idea
of what I saw and where. It\'s a polar projection toward the zenith, as
you would see with a fisheye camera lens. The complete parhelic circle
hung suspended 48 degrees above the horizon centered on the zenith. At
1:30 PM, the sun was slightly west of due south and was surrounded by a
football-shaped circumscribed halo. On the parhelic circle itself were
the sun, the two sun comet-shaped sun dogs (parhelia) flanking the halo,
the two rare 120-degree parhelia, and the rare anthelion. The 120-degree
parhelia looked round, but the anthelion indeed looked like a stubby
vertical line\--accurate, as it is actually where two nearly vertical
arcs (not visible in this display) cross the parhelic circle.

\- 30 -

Author: Trudy E. Bell

Images resembling what I saw:

[http://www.sundog.clara.co.uk/halo/parcirc.htm]{.underline} Photo close
to what I saw, but mine was brighter. I actually had purchased a gazing
globe a year ago to photograph these phenomena, and \*\***forgot\*\***
about it until just now seeing this photo. Nor did I think simply to
photograph a mosaic. Bummer---probably missed my chance at immortality
for that!!

Another photo similar to what I saw, including the two 120-degree
parhelia [http://www.sundog.clara.co.uk/halo/bishop.htm]{.underline} ,
except that although I saw a circumscribed halo, I did not notice any of
the more exotic arcs

The left half of the blue simulation on the right is an accurate
representation of what I saw
[http://www.sundog.clara.co.uk/halo/stpete.htm]{.underline} -- had no
clue until now exactly \*\*how\*\* rare was my display

Photo of rare 120-deg parhelion
[http://www.sundog.clara.co.uk/halo/120im1.htm]{.underline}

Other helpful references:

Trudy E. Bell \"Skyscapes,\" *League of American Bicyclists magazine*,
37 (3): 12-15 (Summer).
[http://home.att.net/\~skyscapes/01summerSkyS.pdf]{.underline} photos of
other neat displays I\'ve taken, along with tips on observing and
photographing such things

Classic book (now out of print, but widely available at libraries):
Robert Greenler, *Rainbows, Halos, and Glories*, with a comprehensive
catalogue of ice crystal forms and the displays they produce, plus
highly useful color photos of many kinds of displays one can see

How-to tips on observing halos
[http://www.sundog.clara.co.uk/halo/p1.htm]{.underline}

[http://www.sundog.clara.co.uk/halo/common.htm]{.underline} common
crystal shapes and orientations giving rise to common phenomena (this is
NOT an exhaustive list of crystals -- some phenomena can be created by
more than one shape and orientation, so will sometimes be paired with or
sometimes without other phenomena)