Sunday, April 10, 2011

1,001 Celestial Wonders to See Before You Die

Format : PDF
Author :  Michael E. Bakich
Publisher : Springer
ISBN 978-1-4419-1776-8
e-ISBN 978-1-4419-1777-5
Size :  18 Mb

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There’s nothing quite like deep-sky observing. Out under an inky black sky filled with stars, your
telescope at your side, armed with lists and ideas about what to look at, the entire universe lies at your
beck and call. And it’s filled with exciting things to look at. The Milky Way Galaxy holds as many as
400 billion stars and the universe at least 125 billion galaxies. Does that mean amateur astronomers
have 50,000 million billion targets for their telescopes? No—there’s no need to get greedy. What can
be seen with a medium-sized backyard telescope amounts to 10,000 nice targets, the objects that are
closest to us in space and therefore the brightest. And in this impressive book you are holding,
Michael Bakich presents more than 1,000 of these targets — star clusters, nebulae, and galaxies —
10% of the good stuff you can see with your scope, in a single book!
Before heading out under the stars, keep the basics in mind. Make sure you get as far away from city
lights as possible, and observe close to the dark of the Moon. Choose areas or nights of good
transparency, when little particle stuff is floating in the atmosphere, and nights of good seeing
when the atmospheric turbulence is at a minimum. Don’t be tempted to jump to high powers as a
key to seeing things: most deep-sky objects are best viewed at relatively low magnifications. If you can,
take along a set of light pollution reduction filters that will help with scattered artificial light. Make
sure you use the basic techniques of backyard observers, such as averted vision—looking to the side
of the eyepiece field, which engages your eyes’ rods, its faint light receptors.

And make sure you enjoy the journey. I’ve owned many telescopes of various sizes but perhaps the
most fun I ever had under the night sky came during my first year of observing in a country field in
Ohio. Back then I had only binoculars and whatever it was—the Dumbbell Nebula, the Andromeda
Galaxy, a star cluster like M7—was a voyage of discovery. I had no idea what could be seen or what
anything would look like, so the feeling of wonder and awe roughly equated to Galileo when he first
gazed upon the heavens, unsure of what anything was at all. In some ways, that sense of wonder was
greater than it is now observing very distant objects with a 30-inch telescope.

As you gain experience as an observer, you’ll gain many friends in the sky—favorite objects you
like to come back to again and again. One of my favorites is NGC 6888, known as the Crescent Nebula.
This glowing cloud was cast off by a furiously hot central star, HD 192163, a Wolf-Rayet star with its
hot, inner layer exposed. On a dark night, an 8-inch scope shows a weird, mottled texture along this
object, floating in a rich field of faint stars. Another strange emission nebula, the Bubble Nebula, lies in the constellation Cassiopeia and is designated NGC 7635. Although this object has a somewhat low
surface brightness, meaning its total light is spread out and made a little challenging to see, a 6-inch
scope shows the Bubble on a dark night.

As you read Michael’s book, you’ll invariably draw up a list of your own favorites, either to go after
before you’ve seen them once, or to return to on subsequent nights. After many nights under the stars
you’ll find this book a valuable reference and, I’m guessing, a constant companion under the stars.

                                                                David J. Eicher

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