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- FIELD TEST: CARL ZEISS APOCHROMATIC & SHARPEST (CZAS) BINOVIEWER
- Omegon 32mm 70º SWA eyepiece review
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- Review of the Hubble Optics 14 inch, f/4.6 Premium Ultra Light Dobsonian Tele...
- My experience with the Starizona Landing Pad
- A quick Review of the MIGHTY MAX 12V 100AH BATTERY
- Nexus II Review
- New Moon Telescopes 20”F/3.3 Review
- FIELD TEST OF THE BAADER MAXBRIGHT® II BINOVIEWER
- My Experience using SkyWatch for the Alphea All Sky Camera from Alcor Systems
- Astroart 7 - A Review and "How To" (Part 1)
- My experience using two 80-millimeter long-focus refractors
CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.
Binocular Universe: Bikini Bottom
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showers may bring May flowers here on Earth, but up in the sky, October is the
soggiest time of year. That's
because the "wet quarter" flows above our southern horizons this
month, bringing with it several constellations that are associated with water in
one way or the other. There are
Capricornus, the Sea-Goat; Aquarius, the Water-Bearer; Piscis Austrinus, the
Southern Fish; Cetus, the Whale; and Pisces, the Fishes.
None are striking from a naked-eye perspective, so you may need to travel
to a site that is free of terrestrial obstructions, low-slung light pollution,
and any horizon-hugging haze to make them out.
this year. That's because these
evenings Capricornus, which always impresses me more as the bottom half of a
bikini than a "sea-goat (whatever that is) plays host to brilliant Jupiter. The king of the
planets draws the attention of
everyone from all quarters to the wet quarter, whether you're in the heart of a
city or somewhere out in the rural countryside.
easily show the four Galilean moons
orbiting Jupiter. These serve as a
fitting tribute to the man who, 400 years ago, solved the thousand-year-old
riddle of which orbits which, Earth around the Sun or the Sun around Earth.
The fact that Galileo saw what he called four "stars" --
originally, the "Medici stars" -- orbiting Jupiter proved that not
everything went around Earth, as Ptolemy's geocentric gospel had prescribed
since about 140 AD.
an aside, as you are showing Jupiter and its moons to family and friends, please
don't commit the same error found in many undergraduate astronomy textbooks by
referring to Jupiter as a "gas giant."
It's not. For most of its
thickness, Jupiter consists of a strange cocktail called metallic hydrogen.
Metallic hydrogen, which is electrically conductive, is not gaseous.
At the pressures and conditions found within Jupiter's interior, metallic
hydrogen is a liquid. So, call it a
"giant planet" or a "Jovian planet," but a "gas
Finder chart for Capricornus. Chart
from TUBA, www.philharrington.net/tuba.htm
giant of the solar system, the eighth planet,
||Algedi (top), Dabih
(bottom), and surroundings, as seen through the author's 10x50
binoculars. North is up and east is to the left in the drawing.
second double star is Dabih, or Beta
(â) Capricorni, is just south of Algedi in the same field of view. While
Algedi's two stars appear identically bright, Dabih's two stars look markedly
different. The brighter sun, called
Dabih-Major, shines at 3rd magnitude, while its companion, Dabih-Minor, is 16
times fainter at 6th magnitude. They
may look different, but studies show that both form a physical system 330 light
years away. Each is separated from
the other by about a third of a light year. As
a result, it takes at least one million years for the pair to orbit one another.
is much more here than meets the eye. Studies
show that Dabih-Minor is a spectroscopic binary dominated by a blue-white giant
that is unusually rich in platinum, gold, mercury, and bismuth.
Dabih-Major is an orange giant that is circled by a close-set pair of
stars. The more massive of those two
is a blue star, but little is known about its companion apart from it taking
only 8.7 days to orbit. The two are
separated from each other by only one-third Mercury's distance from the Sun.
last stop within Capricornus is the constellation’s sole contribution to the
Messier catalog. The 7th-magnitude
globular cluster M30 lies in the
constellation’s barren southeastern corner.
The stars Nashira and Deneb Algedi mark the Sea-Goat's tail and the
eastern point of the Capricornus triangle. Turn
southwest toward the triangle's southern tip, pausing partway along the way at
the 4th-magnitude star Zeta Capricorni. Center
Zeta in your finderscope, then look toward the eastern edge of the field.
A 5th-magnitude star, 41 Capricorni, should just be coming into view.
Center on 41, and then look just to that star's west.
Can you see a dim, round patch of grayish light surrounding a brighter
core? That’s M30.
It will take at least a 6-inch (150-mm) telescope to show any sign of the
100,000 or so individual stars that make up this distant swarm.
That's the view from Bikini Bottom. Comments, questions, suggestions for this column? Post them in the discussion thread or drop me a line. Till next month, when we will once again tour the universe through our binoculars, remember that two eyes are better than one.
Harrington, author of Touring the Universe through Binoculars, is
currently completing a new observing guide of challenging observing
targets for Cambridge University Press, which will be published in late
2010. Visit his web site at www.philharrington.net .
Phil Harrington's Binocular Universe is copyright 2009 by
Philip S. Harrington. All rights
reserved. No reproduction, in whole
or in part, beyond single copies for use by an individual, is permitted without
written permission of the copyright holder.