St. Basil, Doctor of the Church, (d. 379), wrote the
following in the sixth homily of his Hexaemeron,
and I can think of no better way to extend an invitation to tour the
It is because it
is absolutely necessary that all lovers of great and grand shows should
bring a mind well prepared to study them. If sometimes, on a bright
night, whilst gazing with watchful eyes on the inexpressible beauty of
the stars, you have thought of the Creator of all things; if you have
asked yourself who it is that has dotted heaven with such flowers, and
why visible things are even more useful than beautiful; if sometimes,
in the day, you have studied the marvels of light, if you have raised
yourself by visible things to the invisible Being, then you are a well
prepared auditor, and you can take your place in this august and
Come in the same way that any one not knowing a town is taken by the
hand and led through it; thus I am going to lead you, like strangers,
through the mysterious marvels of this great city of the universe.
The focus of
this tour will be to teach about the Zodiacal constellations since they
stars that can be seen from all over the populated areas of the world
and are the ones that St. Paul seems to have had in mind when he
quoted Psalm 18
with his words, "Their sound hath
gone forth into all the earth: and their words unto the ends of the
world." These are also the stars -- along with the
easily visible planets of our solar system -- classically seen as
influencing our inclinations. To this end, I will first give you some
important background information: a way to model the
Before beginning, though, here are a couple of things that might help
you with all this.
Tips and Tools
A few things
that will help you to get the most out of these pages:
Stellarium is a free, open source planetarium program for
Windows, Mac, or Linux. It shows a realistic sky in 3D, just like what
you see with the naked eye, and allows you to look around in all
directions, choosing times and dates and landscapes and all manner of
good things. They have an online
version as well that lets you, after you input your location, see
the sky as it is in the present.
Mobile Plus App: Like the above, but for your phone. Works fine
without an internet connection. "Stellarium Mobile Plus is the next
generation astronomy star map app. It combines a realistic and accurate
night sky simulation with a gigantic amount of online imaging and sky
Walk 2 Free: For your smartphone. "Star Walk 2 Free - Identify
Stars in the Sky Map is a great astronomy guide to explore the starry
sky day and night, find and observe planets, asteroids, comets, ISS,
Hubble Space Telescope, constellations, stars and other celestial
bodies in real time in the sky above you. All you need to do is to
point your device to the sky."
Maps for Beginners: by I. M. Levitt and Roy
K. Marshall. This slight, inexpensive, easy-to-use book has been
described by Sky and Telescope as "The best way to learn the
constellations that we have ever run across." It is designed especially
for those who live around 40o N (a good 20% of the world's
population, according to the book), but will be useful, too, for those
who live within 6o North or South of that exact latitude.
Note the chart on page 15 which helps you select which of its twelve
maps to use for any given date and time.
DarkSite Finder: a website
that helps you find places near you that have the least light
pollution, making for good stargazing.
When going out
to view the stars with your star maps, go as far away as possible from
light. This simply cannot be stressed enough; the differences in the
appearance of the night sky in the typical city as opposed to its
outskirts or, even better, far out in the country, are vast. Drive
outside of the cities, away from brightly lit gas stations and
mini-marts and the street lights that line our roads. Go to the darkest
place you can find, taking with you as a light source a flashlight with
its end wrapped in three layers of red cellophane, and giving your eyes
plenty of time to adjust to the darkness. And why not make it cozy and
take some hot chocolate or coffee and something to snack on while
you're out there? Make it fun!
With a prayer to St. Dominic, the patron Saint of astronomers, 2 let's begin our tour...
of the eloquent Order of Preachers,
and friend of Saint Francis of Assisi,
you were a fiery defender of the Faith
and a fighter against the darkness of heresy.
You resembled a great star that shone close to the world
and pointed to the Light which is Christ.
Help astronomers to study the stars
and admire their wonderful Maker, proclaiming:
"Give glory to God in the highest." Amen.
1 Ptolemy (b. ca. A.D. 90)
could only account for the constellations he could readily see, which
are mostly those easily viewed from the Northern Hemisphere. The
forty-eight he enumerated are:
• Andromeda •
Aquarius • Aquila • Ara • Argo Navis • Aries • Auriga • Bo÷tes
• Cancer • Canis Major • Canis Minor • Capricornus • Cassiopeia •
• Cepheus • Cetus • Corona Australis • Corona Borealis • Corvus •
Crater • Cygnus
• Delphinus • Draco • Equuleus • Eridanus • Gemini • Hercules • Hydra •
• Lepus • Libra • Lupus • Lyra • Ophiuchus • Orion • Pegasus • Perseus
• Piscis Austrinus • Sagitta • Sagittarius • Scorpius • Serpens
• Taurus • Triangulum • Ursa Major • Ursa Minor • Virgo
In the 18th
century, Argo Navis, seen as a great ship in the southern sky, was
split into four constellations: Carina (Keel), Puppis (Stern) , Pyxis
(Compass), and Vela (Sails).
Modern astronomers count eighty-eight constellations, including those
of the Southern hemisphere.
St. Dominic's patronage of star-gazers derives from a story told about
his Baptism. Here it is, from The Golden
Legend (Aurea Legenda),
compiled by Jacobus de Voragine, A.D. 1275:
And his mother,
tofore that he was born, saw in her sleep that she bare a little whelp
[a little dog] in her belly which bare a burning brand [torch] in his
mouth, and, when he was issued out of her womb, he burnt all the world.
And also it seemed to a woman that was godmother to him at the font and
held him, that the child Dominic had a star right clear in his
forehead, which enlumined all the world.