. . y •• v . :4 ' „ ' . . . . • . . . .

V . ' - i V ' f • > ; J v \ By J O A N G I L B E R T S O N a n d G A R Y M U R P H Y *

* . • » y ' O

' ' y / • ": '* ; y p j j ^ at Baylor Regional Park . > t V " v y ^ . V ' * * n e a r Young A m e r i c a in

• i/'VV. ;'> southern Minnesota . Several m e m b e r s of the •* , >>.'* . . . "' - . Minnesota Astronomical Society have rolled '

, ' U - If- , y back the arched roof of the newly built O n a n : ; * ' ' " ' • ' O b s e r v a t o r y . M i k e Kibat , t he o b s e r v a t o r y

' '•*. '• • •','•; guide, is readying the 16-inch telescope for r ^ / ^ ' ^ v - ' a n e v e n i n g ' s p u b l i c e v e n t , w h i l e s o c i e t y 1

: .*>; . . • m e m b e r T o m Y o u n g b l o o d en thus ias t ica l ly (•• ^ V " discusses anything heavenly. t ' : x i'*" 4* • - " I ' m a n e w c o m e r to this hobby," explains '•'.•

''V 1 ./ •' (V. '«

, MILKY WAY, 9-MINUTE EXPOSURE THROUGH 50MM LENS '

' V '* \ MVEALS FAR MORE LIGHT THAN MEETS THE NAKED EYE.

- ' v V f . . . - • B Y LAUREN N. NELSON

HEAVENS. THEY CAME BACK SMITTEN BY THE STARGAZER BUG.

2.5-DAY-OLD CRESCENT M O O N

ROD NERDAHL

Youngblood, a trim, engaging man near retirement age. "But I've started by mem-orizing all 88 constel la t ions . Did you know that's the same as the number of keys on a piano?"

In about an hour, more society members and a mix of curious visitors (us included) will be treated to the first astronomical wonder of the night: a 1-day-old moon, one of the most slender imaginable arcs of

Joan Gilbertson, former DNR video news producer, is a news producer for WCCO television. Gary Murphy is a copywriter for The Sportsman's Guide catalog.

moonlight. A white sliver barely noticeable against the deepening blue of the sky, it is the very edge of the moon catching the sun's light.

Just the night before, the moon rose and set with the sun, creating a moonless night, a phase known as the new moon. H e r e ' s a g l o r i o u s c o n t r a d i c t i o n for stargazers: The more full, large, and gor-geous is the moon, the more it obscures our view of other celestial objects.

Kibat shows slides as we wait for the sky to darken. Adults and children alike marvel at his color pho tos of planets, galaxies, and nebulae—huge clouds of interstellar gas and dust measuring many

2 4 M I N N E S O T A C O N S E R V A T I O N V O L U N T E E R

ANDROMEDA, 12-MINUTE EXPOSURE THROUGH A 400MM LENS

LAUREN N. NELSON

light-years across. "There's nothing like a dying-star nebula," he says. "It 's awe-inspiring and humbling."

By 9 p.m., the sun 's light has fallen significantly below the hor izon, while the lights of the surrounding communi-ties have begun to glow upward. Society m e m b e r s have c a r e f u l l y set u p and adjusted their telescopes, many with a focus on Mars. In its closest approach to Earth in a decade, Mars is the "star" of the show tonight, reflecting the light of the sun.

A society member points out an actual star close to Mars and, to the naked eye, similar in appearance. Our knowledge-

J A N U A R Y - F E B R U A R Y 2 0 0 2

able friend informs us, "That's Antares," which means, in Greek, "like Mars."

This pleasant evening is our initiation into the universe of stargazing as a hobby. It's free and easily available to anyone with a pair of eyes (and for a somewhat better view, binoculars or a small telescope). Just a little information and a few star charts will allow you to enter into a fascinating activity to be enjoyed for a lifetime.

NOTES FOR "NEWBIES" Following our outing with the astronomi-cal society, and all the lofty thoughts of the heavens it inspired, we began to won-der about the nuts and bolts (or should

2 5

that be charts and lenses?) of pursuing amateur astronomy. Here are a few of the things we learned.

First, somewhat to our surprise, obser-vation with binoculars was not looked down on by any of the serious sky-people we spoke to. Because of their portability and easy use, binoculars are actually rec-o m m e n d e d for beginners . Binoculars with 7x to lOx magnification and a large 50mm objective lens are good for casual use; higher power than that requires a tri-pod for stability.

After trying out a variety of telescopes at astronomy events and learning what to look for, a dedicated amateur will want to move up to a telescope, perhaps eventual-ly one with a tracking system and larger light-gathering lenses or mirrors.

When deciding when to stargaze, con-sider seasonal benefits and drawbacks. Insects in the summer. Cold feet in the winter. No glare from snow in the sum-mer. (The reflectivity factor of snow is considered to be 70 percent vs. just 10 percent from asphalt.) Drier air and there-

Light Pol lut ion:

M i g h t I See a

Star Ton ight?

Th e n i g h t s k y a n d t h e h e a v e n l y b o d -

i e s t h a t p o p u l a t e i t h a v e l o n g s e r v e d

a s p o e t i c s y m b o l s o f e t e r n i t y , p e r m a -

n e n c e , a n d

i n f i n i t y . S o

i t ' s d i f f i c u l t

t o t h i n k o f a

s t a r r y n i g h t

a s a r e s o u r c e

t h a t c o u l d

f a d e , e v e n d i s a p p e a r . S a d l y , t h o u g h , f o r

m o d e r n s t a r g a z e r s — w h e t h e r p r o f e s -

s i o n a l a s t r o n o m e r s o r h o b b y i s t s — t h e r e

h a s i n d e e d b e e n a l o s s in t h e n i g h t s k y .

T h i s h a s c o m e b y w a y o f a p r o b l e m a n y

o n e o f u s m a y i n n o c e n t l y c o n t r i b u t e t o :

l i g h t p o l l u t i o n .

A s t r o n o m e r s h a v e l o n g r e c o g n i z e d t h a t

r e s i d e n t i a l a n d c o m m e r c i a l d e v e l o p m e n t

is e a t i n g a w a y a t t h e d a r k n e s s , d i m i n i s h -

i n g t h e n i g h t s k y . M u c h o f t h e p r o b l e m

is d u e t o p o o r l y d e s i g n e d l i g h t i n g , w h i c h

c a u s e s " l i g h t t r e s p a s s " ( l i g h t s h i n i n g

o u t w a r d a n d u p w a r d w h e r e i t is w a s t e d )

White marks the

areas with the

greatest artificial

Eg?.- v*. ^-H^^prCTW^pjK^ Eft JJKM brightness,

followed by red,

orange, yellow,

green, blue, dark

gray, and black.

MtoWIMHMI

PIERANTONIO CINZANO. FA8IO FALCHI, AND CHRIS ELVIDCE. COPYRIGHT ROYAL ASTRONOMICAL SOCIETY

2 6 M I N N E S O T A C O N S E R V A T I O N V O L U N T E E R

HALE-BOPP OVER WELL-LIGHTED CITYSCAPE

LAUREN N. NELSON

a n d g l a r e ( l i g h t b r i g h t e r t h a n o u r e y e s

c a n p r o c e s s ) .

" T h e a m o u n t o f w a s t e d ' u p ' s t r e e t

l i g h t in t h e U . S . c o u l d p r o v i d e a l l t h e

e l e c t r i c i t y f o r a c o u n t r y t h e s i z e o f

I r e l a n d o r I s r a e l , " s a y s I n t e r n a t i o n a l

D a r k - S k y A s s o c i a t i o n m e m b e r D a n i e l

B r o c i o u s . T h e a s s o c i a t i o n e s t i m a t e s

t h a t u p t o 3 0 p e r c e n t o f o u t d o o r l i g h t -

i n g in t h e U n i t e d S t a t e s is w a s t e d , a t a

c o s t o f m o r e t h a n $ 1 . 5 b i l l i o n a n n u a l l y .

M a n y s k y w a t c h e r s w o r r y t h a t t o d a y ' s

c h i l d r e n w i l l n e v e r h a v e t h e o p p o r t u n i -

t y t o f u l l y a p p r e c i a t e t h e b e a u t y o f t h e

s t a r s b e c a u s e o f t h i s p o l l u t i n g w a s h o u t .

F o r t u n a t e l y , t h e r e a r e h i n t s o f a

b r i g h t e r f u t u r e f o r d a r k s k i e s . C o n c e r n s

a b o u t t h e c o s t a n d a v a i l a b i l i t y o f e n e r -

g y h a v e e n c o u r a g e d m a n y m u n i c i p a l i -

t i e s t o f o c u s o n t u r n i n g d o w n t h e

I I

J A N U A R Y - F E B R U A R Y 2 0 0 2

S/l/ME COMET IN DARK SKY

l i g h t s , t h e r e b y t u r n i n g u p t h e s t a r s .

T h e D a r k - S k y A s s o c i a t i o n is e d u c a t i n g

c o n s u m e r s , b u s i n e s s e s , a n d g o v e r n m e n t

a b o u t t h e b e n e f i t s o f s w i t c h i n g f r o m

i n e f f i c i e n t m e r c u r y v a p o r l i g h t s t o

l o w e r - w a t t a g e , l o w - p r e s s u r e s o d i u m

b u l b s . T h e a s s o c i a t i o n a l s o r e c o m m e n d s

u s i n g f u l l - c u t o f f l i g h t i n g f i x t u r e s t h a t

e m i t n o l i g h t a b o v e t h e h o r i z o n t a l

p l a n e r a t h e r t h a n u n s h i e l d e d " g l a r e

b o m b s . " M o r e t h a n 1 0 0 c i t i e s a n d c o u n -

t i e s , p l u s a h a n d f u l o f s t a t e s , a r e i m p l e -

m e n t i n g t h e s e s i m p l e , i n e x p e n s i v e m o d -

i f i c a t i o n s t o d i m i n i s h l i g h t d o m e s

a r o u n d d e v e l o p e d a r e a s .

" T h i s is t r u l y a s o l v a b l e e n v i r o n m e n t a l

p r o b l e m , " s a y s B r o c i o u s . " I t ' s n o t l i k e

t r y i n g t o r e m o v e a l l t h e s t y r o f o a m

p e a n u t s f r o m t h e o c e a n . "

Joan Gilbertson

2 7

THE CONSTELLATION PLEIADES-THE SEVEN SISTERS OF CREEK MYTHOLOGY

LAUREN N. NELSON

fore clearer views in the winter. Earlier sunsets, longer nights in the winter. Each season has its own favori te sights. Of course, for the dedicated, the hooked, the answer to when to stargaze is "Always!"

TOP EIGHT SPECTACLES As an amateur astronomer, you must real-ize that you're not looking for the huge, colorful images seen in astronomy maga-zines, nor for anything you've seen in a sci-fi movie. We learned about some of what is worth looking for when we attended the annual convention of the Astronomical Society of the Pacific held recently in St.

Paul. Bob Berman, astronomer and popu-lar columnist for Astronomy and Discover magazines , p r e sen t ed a lec ture : The Greates t Sky Spectacles of the 21st Century. Here are notes on some of the most common and easy sights to see. s

o

Moon. Earth's satellite is the hands-down g winner in terms of spectacle, and a good t starting place. You've likely looked at it § before, as people through the ages have. s

It was the huntress-goddess Diana to | the R o m a n s , a rabb i t w h o mixes the >

<

potions of life to the Chinese, and simply a < man ' s face looking down on Earth to "

2 8 M I N N E S O T A C O N S E R V A T I O N V O L U N T E E R

many others. Observation with even low-powered binoculars reveals a landscape of m o u n t a i n s , r idges, seas, and cra ters . Anticipating the moon's phases as it waxes and wanes f rom new to crescent to full and back again, can be a lot of fun and a great science lesson for children. It also tells you the best t ime to do the rest of your astronomy.

Milky Way and Other Galaxies. The Milky Way and other galaxies are huge groups of stars, bound together by grav-ity. Viewing the Milky Way is a simple naked-eye experience. The tricky part is getting to a place that's dark enough to really see the river of celestial bodies in all its glory (see Light Pollution, page 26). There are likely 200 billion stars in the Mi lky Way, t h e galaxy we res ide in. Observing it is just taking a peek around our neighborhood. The awe is in appreci-ating the fact that 200 billion is just a tiny fraction of the stars in the universe.

As majestic as galaxies are, they're often descr ibed as gray l int when first seen through a telescope. Berman warns star enthusiasts against showing Andromeda to newcomers. "Stay away from Andromeda," he says of this large spiral galaxy that is usu-ally visible to the naked eye. "People expect a galaxy to look like the movie image. But t h rough a telescope it 's just a piece of smudge. And you're going to look like a PR person from an antimatter planet."

Stars and Constellations. One of the easi-est cons t e l l a t ions to recognize is t he hunter Orion with his distinct belt of three stars, shining so prominently in the south-ern part of the winter sky.

32 M I N N E S O T A C O N S E R V A T I O N V O L U N T E E R

As inhabitants of the North Star State, we surely should be looking for Polaris. The North Star is part of the Little Dipper, which is a part of the constellation Ursa Minor, the Little Bear, and near the Big Dipper, which is the hindquarters and tail of the Big Bear, Ursa Major. The British call the Big Dipper the Plough, and escap-ing slaves in the 1800s fo l lowed the Drinking Gourd north to freedom.

You can look for your own constella-tion of the zodiac, be it Taurus, Scorpius, Leo, Sagittarius, or one of the others.

According to a Cheyenne legend, the entire dome of the sky was considered the Great Turtle, its shell glittering with the ax heads, spear points, and skeletons of brave warriors who climbed on it.

P l a n e t s . O n e can usual ly d i s t inguish planets f r o m stars and o ther celestial objects by the fact that they don ' t "twin-ROD NERDAHl

k le" as m u c h as s t a r s do . Look f o r Sa tu rn ' s r ings and one of its m o o n s , Ti tan, the largest satellite in the solar system. In addition to Mars, Venus and Mercury can be easily observed with the n a k e d eye. As e v e n i n g o r m o r n i n g " s t a r s , " V e n u s a n d M e r c u r y t r ave l across the sky as their positions relative to E a r t h c h a n g e . T h e c h a l l e n g e in observing Jupiter is actually discerning its G r e a t Red Spo t , a h u r r i c a n e l i k e storm more than 15,000 miles long, first observed in 1664.

Me teo r Showers . Lying on the picnic table or the dock up at the lake, mar-veling at a n igh t tha t seemed loaded wi th " s h o o t i n g s t a r s , " d id you ever guess that there is a regular schedule for the best meteor showers, about as close to clockwork as one can get? As Earth orbits the sun, it encounters the same

Cyberspace

S targaz ing

a s t r o . u m n . e d u / O u t r e a c h / p u b _ o u t . h t m l

T h i s U n i v e r s i t y o f M i n n e s o t a

D e p a r t m e n t o f A s t r o n o m y w e b s i t e h a s

i n f o r m a t i o n a b o u t p u b l i c o u t r e a c h p r o -

g r a m s a n d l i n k s t o v a r i o u s s k y c h a r t s a n d m a p s , a s w e l l a s

i m a g e s f r o m t h e H u b b l e s p a c e t e l e s c o p e .

a s t r o n o m y . c o m / T h i s Astronomy m a g a z i n e s i t e o f f e r s s c i e n c e

a n d f e a t u r e s t o r i e s , g r e a t p h o t o g r a p h s , a n d a s p e c i a l s e c -

t i o n f o r k i d s .

d a r k s k y . o r g T h e I n t e r n a t i o n a l D a r k - S k y A s s o c i a t i o n s i t e h a s

i n f o r m a t i o n r e l a t e d t o i t s g o a l : " T o p r e s e r v e a n d p r o t e c t

t h e n i g h t t i m e e n v i r o n m e n t a n d o u r h e r i t a g e o f d a r k s k i e s

t h r o u g h q u a l i t y o u t d o o r l i g h t i n g . "

f o u r m i l a b . c h / y o u r s k y / T h i s s i t e a l l o w s y o u t o e n t e r y o u r

l o n g i t u d e a n d l a t i t u d e t o g e t a v i r t u a l v i e w o f t h e n i g h t s k y

in a n y d i r e c t i o n .

l i g h t p o l l u t i o n . i t / d m s p B a s e d o n s a t e l l i t e d a t a a n d o t h e r

c a l c u l a t i o n s , t h i s w o r l d a t l a s o f a r t i f i c i a l n i g h t s k y b r i g h t -

n e s s — b y P i e r a n t o n i o C i n z a n o , F a b i o F a l c h i , a n d C h r i s

E l v i d g e — s h o w s t h e e x t e n t a n d s e v e r i t y o f l i g h t p o l l u t i o n .

m n a s t r o . o r g / o n a n / e v e n t s . h t m M i n n e s o t a A s t r o n o m i c a l

S o c i e t y a n n o u n c e s t h e O n a n O b s e r v a t o r y ' s " s t a r p a r t i e s "

a n d o t h e r n e w s .

s k y p u b . c o m / P r o d u c e d b y Sky if Telescope m a g a z i n e , t h i s

s i t e h a s e x p e r t a d v i c e f o r b a c k y a r d s t a r g a z i n g , a s w e l l a s

w e e k l y a n d m o n t h l y s k y c h a r t s .

Joan Cilbertson

clouds of me teoro ids—in te rp lane ta ry d e b r i s — e v e r y year . T h e m e t e o r o i d s strike Earth's atmosphere like bugs on a windshie ld , b u r n i n g up as they enter the atmosphere.

Although the Leonid meteor shower this past November will be hard to beat, the Quadrant ids will be a major event, peaking a r o u n d Jan. 3 with abou t 85 meteors per hour . Probably the most spectacular showers in 2002 will appear

LAUREN N. NELSON

f r o m t h e c o n s t e l l a t i o n P e r s e u s in August, peaking mid-month with 40 to 60 meteors per hour.

Comets . C o m e t s are large masses of frozen materials (sometimes described as dirty snowballs) that travel in long, elliptical orbits a round the sun. These are no t t he bes t s t a r t i n g p o i n t fo r a beginner , because they do not appear often. Two of the best came around just

3 2 M I N N E S O T A C O N S E R V A T I O N V O L U N T E E R

1997 COMET HALE-BOPP, 200MM, 5-/WNUTE EXPOSURE

I

recently. Hale-Bopp was incredibly huge and bright, visible even at dusk in big cities loaded with light. Hyakutake had a tail s t retching some 45 degrees across the sky.

Artificial Satellites. This is kind of cheating because the many communications, weath-er, and other satellites are not natural celes-tial objects. But it can be fun to spot and follow them. Look for an especially brilliant

pinpoint of light that's clearly in motion.

Aurora Borealis. The n o r t h e r n lights shimmer and flow through the sky as if afire with vibrant red or eerie green. The aurora is the result of Earth's magnetic field being disturbed by solar storms. It is a phenomenon similar to the working of a color television: charged particles glow d i f f e r e n t co lors , d e p e n d i n g on the i r chemical makeup. Aurora borealis occurs

J A N U A R Y - F E B R U A R Y 2 0 0 2 3 3

a round the nor th magnetic pole. It is produced in the outer atmosphere when atomic particles strike and excite atoms.

The past several years have been partic-ularly strong in solar activity. Living in a nor thern latitude, Minnesotans have a great seat for the show. According to Berman, the most mind-boggling display of the aurora comes the year after strong solar storms. This March, northern lights are expected to be particularly spectacular.

ANY QUESTIONS? Why, of cour se you have q u e s t i o n s . Aspiring amateur as t ronomers realize that looking at the stars, planets, galaxies,

and other celestial phenomena is only part of the experience. There 's always m o r e to k n o w (see Cyberspace Star-gazing, page 32, and Astronomy Events, below). There are the charts, telescopes, and other gadgetry to be mastered; the cycles of the planets, constellations, and meteors to be learned; the mathematics of distances and magnitudes to be calcu-lated; the causes of astrophysical phe-nomena to be studied; the literary and mythological significance of the heavens to be pondered. And on top of all that, there's always the opportunity to go out and share the pleasure of hobby astrono-my with other stargazers! 9

Th e n i g h t s k y is

t h e f o c u s o f

a t t e n t i o n a t t h e

f o l l o w i n g e v e n t s

a n d a c t i v i t i e s t h i s w i n t e r a n d s p r i n g .

H e n n e p i n P a r k s : O u r W i n t e r S k y , J a n .

1 0 , 9 p . m . , E a s t m a n N a t u r e C e n t e r ,

O s s e o ; S t a r G a z i n g , J a n . 1 8 , 7 p . m . ,

C l e a r y L a k e R e g i o n a l P a r k , P r i o r L a k e .

R e g i s t e r e a r l y f o r e i t h e r e v e n t b y

c a l l i n g 7 6 3 - 5 5 9 - 6 7 0 0 .

M i n n e a p o l i s P l a n e t a r i u m : W i n t e r S t a r

S h o w , J a n . 1 2 - A p r i l 1 8 ; p r o g r a m s

i n c l u d e S p a c e D r e a m s , D i n o s a u r s in

t h e D a r k o f N i g h t , T h e r e ' s N o P l a c e

L i k e S p a c e , F o l l o w t h e D r i n k i n g G o u r d ,

a n d R o m a n c i n g t h e S t a r s . Ca l l

6 1 2 - 6 3 0 - 6 1 5 5 .

M i n n e s o t a A s t r o n o m i c a l S o c i e t y

" s t a r p a r t i e s , " v i e w i n g e v e n t s f o r t h e

p u b l i c : M a r c h 1 a n d 2 9 , M e t c a l f

N a t u r e C e n t e r , A f t o n ; M a r c h 8 , C h e r r y

G r o v e O b s e r v a t o r y , s o u t h o f C a n n o n

F a l l s ; M a r c h 1 5 , B a y l o r R e g i o n a l P a r k ,

Y o u n g A m e r i c a . If w e a t h e r p r e v e n t s

v i e w i n g f o r a F r i d a y s t a r p a r t y ,

v i e w i n g is r e s c h e d u l e d t o S a t u r d a y .

T o c o n f i r m v i e w i n g c o n d i t i o n s o r f o r

d i r e c t i o n s , c a l l t h e s o c i e t y a t

6 5 1 - 6 4 9 - 4 8 6 1 .

M i n n e s o t a V a l l e y N a t i o n a l W i l d l i f e

R e f u g e : T h e r e ' s a B e a r in M y S k y ! L e a r n

h o w p r e h i s t o r i c p e o p l e v i e w e d t h e

n i g h t s k y , J a n . 2 3 , 7 - 8 : 3 0 p . m . , B l o o m -

i n g t o n , 9 5 2 - 8 5 4 - 5 9 0 0 .

U n i v e r s i t y o f M i n n e s o t a D e p a r t m e n t

o f A s t r o n o m y : p u b l i c v i e w i n g F r i d a y s ,

8 - 9 : 3 0 p . m . w e a t h e r p e r m i t t i n g , T a t e

L a b o r a t o r y o f P h y s i c s , M i n n e a p o l i s ,

6 1 2 - 6 2 4 - 3 8 5 9 ; p u b l i c t o u r s o f 3 0 - i n c h

t e l e s c o p e b y a p p o i n t m e n t , O ' B r i e n

O b s e r v a t o r y , M a r i n e o n S t . C r o i x , 6 1 2 -

6 2 4 - 7 8 0 6 .

Mary Hoff

3 4 M I N N E S O T A C O N S E R V A T I O N V O L U N T E E R

AURORA BOREAUS IN OCTOBER NEAR FOREST LAKE