Amateur Astronomy Magazine

80 Pages·2015·2.66 MB·English

by  Charles Warren

Amateur
Astronomy
M a g a z i n e
The Essential Journal for Amateur Astronomers Around the World!
How To Create A Beautiful Time Lapse
Tips and techniques from author Alan Dyer
Merging Images in a
Binoscope
Star People
Get to know Pranvera Hyseni from Kosovo
Imaging Venus
in Ultraviolet Light
Observing
Deep Sky Treasures
Unobserved Nebulae
Focus on the Moon
Looking South
Sunspots
Four Lessons in Optics
From Master Mirror Maker Mike Lockwood
Issue 86
Spring 2015 $6.50 US
2 www.AmateurAstronomy.com Spring 2015 Issue # 86
Amateur Astronomy
Managing Editor: Charlie Warren
Contributing Editors: Robert Reeves, John Davis, Harry Roberts, Howard Banich, Scott Rosen, Mike Smith, Tom Clark
Webmaster: Charlie Warren
Amateur Astronomy is published quarterly by Charlie Warren (615)-332-5555
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Mailing dates are approximately: Winter (1/1), Spring (4/1), Summer (7/1), Fall (10/1). Delivery takes up to four weeks in the USA.
In this issue: Our Star Supporters
Cover: Image Alan Dyer - see details on page 6 OPT Oceanside Photo & Telescope Back cover
Celestron - page 2, 35
4 Editorial
ScopeStuff - page 4
7 Short Subjects
Sky Watcher - page 5
10 Merging Images in a Binoscope - Arie Otte
Eyepieces Etc. - page 8
16 Unobserved Nebulae- Mel Bartels
Howie Glatter’s Lasers- page 15
20 Focus On The Moon with Robert Reeves
Jack’s Astro - page 19
22 Shorts From Down Under - Mike Smith Replacement Eyepiece Caps page 25
24 On The Moon - Harry Roberts Equatorial Platforms - page 26
26 Star Party and Astronomical Events Calendar Meade Instruments page 31, 71
28 Deep Sky Treasures Spring Galaxies John Davis Space Images.com- page 42
RSpec Spectroscopy - page 42
36 Star People - Pranvera Hyseni by Robert Reeves
Charlie Bates Astronomy - page 45
40 Imaging Venus in Ultraviolet Lightby Rick Schrantz
Nightscapes & Time Lapses page 56
44 Creating a Solar Mosaic - by Craig & Tammy Temple
21 Years of Amateur Astronomy page 57
46 How to Process Time Lapses by Alan Dyer
Catseye Collimation System page 70
58 Sunspots by Harry Roberts
HoTech- page 71
60 Four Lessons in Mirror Testing - by Mike Lockwood
72 Parting Shots Astro men and women Please thank our sponsors for supporting
AA and support them in return!!
Don’t forget to mention that you saw their advertise-
ment here. They are some of the good guys in this
hobby who make this publication possible.
Spring 2015 Issue # 86 www.AmateurAstronomy.com 3
Editorial
comments and updates from the Editor
Our Star Person this issue is a young college
student from Kosovo who has been making
waves through her efforts to expand astrono-
my awareness and education in that country.
I think you will be inspired by what she has
been able to accomplish with fairly limited
resources (initially). I believe we will be
hearing more from Ms. Hyseni in the future
as her passion for astronomy and outreach
will undoubtably reach beyond her countries
borders.
We are starting a new series entitled “Focus
on the Moon with Robert Reeves”. If you
have been reading this magazine for any peri-
od of time, or been anywhere in proximity to
Robert, you know that he is not only a lunar
enthusiast, but also truly an expert on lunar
I features and techniques to image the moon.
n this issue we have two feature length articles. Most
Robert will showcase two areas each issue with high resolu-
publications simply do not have the editorial license to
tion images and descriptions of the lunar terrain selected.
run articles that are 10-11 pages long, but I felt that both
of these articles deserved not only the space allocated, but
I first met Rick Schrantz about 10 years ago at the Chiefland
would suffer if split into multiple parts. The cover story is
astronomy village, and would catch up with him frequently
by Alan Dyer. I have been a fan of Alan’s writing for a while
thereafter at the Winter Star Parties. Rick is a very focused
and his new iBook on Time Lapse is a tremendous resource
planetary imager. He constructed a telescope particularly for
so I asked him if he would give us a short course for AA. He
that purpose. Three years ago at WSP he was imaging using
graciously agreed. Time lapse and “Nightscapes” are
ultraviolet filters, and explained that he was getting particu-
becoming even more popular of late and with good reason.
larly good results with Venus. He had promised an article for
From an astrophotography standpoint, they are not nearly as
some time and finally delivered. Venus is not an easy imag-
investment intensive, the learning curve is much faster and
ing target, but Rick has found a way to extract nice detail by
the new DSLRs are remarkably capable of producing high
imaging with an ultraviolet filter. His results are some of the
quality content. If you have not tried it yet, I encourage you
best I have seen from an amateur.
to read the article and give it a go. If you have as much fun
as I think you will have, get Alan’s iBook and learn how to We ran a couple of articles comparing mono mirror scopes
be a pro at it. with bino scopes. Arie Ott tackles the challenge of getting
images to converge in a binoscope so that owners can get the
Our second feature article is by master mirror maker Mike
most out of their instruments in his article with practical
Lockwood. For those who know Mike, it is not news that he
solutions.
can be a bit obsessive about the quality of his mirror’s
continued on page 6
optics. He is an engineer by education and trade so his
approach to solving problems is quite thorough and method-
ical. It is fun to watch him in action diagnosing problems. In
this article, he goes through the process of testing a 28” mir-
ror that was reported as having optical issues. I promise you
will learn a lot about the optics of your mirror by following
his search for the cause.
Photo Caption Correction (issue 85): I was delighted to
read Tom Clark's account of the Oregon Star Party in issue
#85 of Amateur Astronomy, and to see my binocular scope
featured so prominently on page 13. Unfortunately the
caption for the four photos on that page attributes all of the
scopes to me, whereas the two photos on the left are of
Frank Szczepanski's binocular scopes.
Thanks, Jerry Oltion
4 www.AmateurAstronomy.com Spring 2015 Issue # 86
Spring 2015 Issue # 86 www.AmateurAstronomy.com 5
Cover Photo Details: The Milky Way over Athabasca Glacier and the Columbia Icefields in Jasper National
Park, Sept 14, 2014 on a very clear night before moonrise. The centre of the Galaxy area in Sagittarius is set-
ting in the southwest behind the Icefields. The foreground light on the moraines is wash from lights on the
Glacier View Inn and Icefields Centre. Other ground illumination on the peaks is from starlight though the tops
of the peaks are just being lit by light from the rising waning Moon which is also beginning to light the sky a
deep blue. Mt. Andromeda is at left. The Summer Triangle stars are at center.
This is a composite of 5 shots, tracked, for the sky, blended in Lighten mode and 4 shots, untracked, for the
ground, blended in Mean combine mode to reduce noise. The trailed sky is masked out of the ground shots and
the trailed ground is masked out of the sky shots, so both ground and sky are sharp but the sky has the benefit
of the longer exposures required to really bring out Milky Way details. Each sky shot was 3 minutes and each
ground shot was 4 minutes, all at f/3.2 with the 15mm lens and filter-modified Canon 5D MkII at ISO 1600.
Tracked on the Sky-Watcher Star Adventurer, with the drive turned off for the ground images at the end of the
sky exposures.
Mel Bartels is a very accomplished telescope maker with a astronomers I meet are about 4 to 1 female. From interaction
long history of innovative approach. In his article with amateur astronomers online, I have been astounded at
“Unobserved Nebula” he presents some challenging objects the growth in interest in some other countries, India in par-
for you to attempt with a rich field telescope, but also an ticular, but many others as well. Our Star Person this month
interesting alternative to using multiple eyepieces. Check out is just one example. That makes sense as many countries are
his logic to the concept of “one eyepiece, multiple scopes”. becoming increasingly modernized with countries like China
and India yielding a larger percentage of the population with
On my Facebook page and on several other online venues
disposable income and accessible technology.
there have been some interesting conversations about
whether the hobby of astronomy is dying or growing stale. I would love to hear more about your thoughts and experi-
The evidence was the apparent lack of diversity and advanc- ence on this topic and invite you to write me (editor@ama-
ing age of the average amateur astronomer. If I were to draw teurastronomy.com), particularly about youth and astrono-
a conclusion based on our subscribers, which are predomi- my. I would also like to profile more of our up and coming
nantly male and predominantly ages 45-75, I would come to young astronomy enthusiasts, so send some suggested can-
that conclusion as well. There is no question that amateur didates. I know they are out there and it behooves each of us
astronomy requires some disposable income, and astropho- to participate in activities that will encourage engagement of
tography a significant amount more, but there is also some the next generation of amateur astronomers. From the brief
very affordable technology currently available. questionnaires that we send to each new subscriber, a very
large percentage had experiences at an early age that initiat-
The interesting demographic and exception to this are a
ed their interest, which they later had time and resources to
growing number of new subscribers who are 18-25 and
pursue in greater depth.
mostly female. That matches what I am seeing at outreach
Clear skies! Charlie.
events as well. In the United States, the younger amateur
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6 www.AmateurAstronomy.com Spring 2015 Issue # 86
SShhoorrtt SSuubbjjeeccttss
THINGS YOU REALLY OUGHT TO 12.Murphy's Law of Lockers - If there are black holes, and all large galaxies have one.
KNOW...Laws not taught in Physics... only 2 people in a locker room, they will The one at the center of our galaxy, the
have adjacent lockers. Milky Way, is called Sagittarius A* (or, Sgr
1 .Law of Mechanical Repair - After your A*, as it is called), and scientists estimate
13. Law of Physical Surfaces - The chances
hands become coated with grease, your that it contains about four and a half million
of an open-faced jelly sandwich landing
nose will begin to itch. times the mass of our Sun.
face down on a floor are directly correlated
2. Law of Gravity - Any tool, nut, bolt, to the newness and cost of the carpet or rug. Scientists working with Chandra have
screw, when dropped, will roll to the least observed Sgr A* repeatedly since the tele-
14.Law of Logical Argument - Anything is
accessible place in the universe. scope was launched into space in 1999.
possible IF you don't know what you are
Haggard and fellow astronomers were orig-
3. Law of Probability - The probability of talking about.
inally using Chandra to see if Sgr A* would
being watched is directly proportional to the
consume parts of a cloud of gas, known as
15. Law of Physical Appearance - If the
stupidity of your act.
G2.
clothes fit, they're ugly.
4.Law of Random Numbers - If you dial a
“Unfortunately, the G2 gas cloud didn’t pro-
16.Law of Public Speaking -- A CLOSED
wrong number, you never get a busy signal;
duce the fireworks we were hoping for
MOUTH GATHERS NO FEET!
someone always answers.
when it got close to Sgr A*,” she said.
17.Law of Commercial Marketing Strategy “However, nature often surprises us and we
5. Variation Law - If you change lines (or
- As soon as you find a product that you real- saw something else that was really excit-
traffic lanes), the one you were in will
ly like, they will stop making it OR the store ing.”
always move faster than the one you are in
will stop selling it!
now.
Haggard and her team detected an X-ray
18. Doctors' Law - If you don't feel well, outburst last September that was 400 times
6.Law of the Bath - When the body is fully
make an appointment to go to the doctor, by brighter than the usual X-ray output from
immersed in water, the telephone will ring.
the time you get there, you'll feel better. But Sgr A*. This “megaflare” was nearly three
7.Law of Close Encounters - The probabil- don't make an appointment and you'll stay times brighter than the previous record hold-
ity of meeting someone you know sick. er that was seen in early 2012. A second
INCREASES dramatically when you are enormous X-ray flare, 200 times brighter
with someone you don't want to be seen If you don't share this with at least 5 of your than Sgr A* in its quiet state, was observed
with. friends, your belly button will unscrew. with Chandra on October 20, 2014.
Really... It's true. I read it on the Internet!
8 .Law of the Result - When you try to prove Haggard and her team have two main ideas
to someone that a machine won't work, IT about what could be causing Sgr A* to erupt
WILL !!! in this extreme way. One hypothesis is that
the gravity of the supermassive black hole
Amherst College Astronomy
9 .Law of Biomechanics - The severity of
has torn apart a couple of asteroids that wan-
the itch is inversely proportional to the Professor Detects Record-Breaking
dered too close. The debris from such a
reach. Black Hole Outburst
“tidal disruption” would become very hot
Last September, after years of watching, a and produce X-rays before disappearing for-
10.Law of the Theater & Hockey Arena - team of scientists led by Amherst College ever across the black hole’s point of no
At any event, the people whose seats are fur- astronomy professor Daryl Haggard return (called the “event horizon”).
thest from the aisle, always arrive last. They observed and recorded the largest-ever flare
are the ones who will leave their seats sev- in X-rays from a supermassive black hole at “If an asteroid was torn apart, it would go
eral times to go for food, beer, or the toilet the center of the Milky Way. The astronom- around the black hole for a couple of hours
and who leave early before the end of the ical event, which was detected by NASA’s – like water circling an open drain – before
performance or the game is over. The folks Chandra X-ray Observatory, puts the scien- falling in,” said colleague and co-principal
in the aisle seats come early, never move tific community one step closer to under- investigator Fred Baganoff of the
once, have long gangly legs or big bellies standing the nature and behavior of super- Massachusetts Institute of Technology in
and stay to the bitter end of the performance. massive black holes. Cambridge, MA. “That’s just how long we
The aisle people also are very surly folk. saw the brightest X-ray flare last, so that is
Haggard and her colleagues discussed the an intriguing clue for us to consider.”
11. The Coffee Law - As soon as you sit flare today at a press conference during this
down to a cup of hot coffee, your boss will year’s meeting of the American If that theory holds up, it means astronomers
ask you to do something which will last until Astronomical Society in Seattle. have found evidence for the largest asteroid
the coffee is cold. ever to be torn apart by the Milky Way’s
Supermassive black holes are the largest of black hole.
Spring 2015 Issue # 86 www.AmateurAstronomy.com 7
and the Chandra data are allowing near-infrared data collected by the European
Another, different idea is that the magnetic
astronomers to better understand this unusu- Southern Observatory’s survey VISTA to
field lines within the material flowing
al object. find four young stars approximately
towards Sgr A* are packed incredibly tight-
300,000 light years away. These young stars
ly. If this were the case, these field lines As for the G2: Astronomers estimate that the
are Cepheid variables–“standard candles”
would occasionally interconnect and recon- gas cloud made its closest approach—still
that astronomers use to measure distances.
figure themselves. When this happens, their about 15 billion miles away from the edge
According to Chakrabarti, these are the
magnetic energy is converted into the ener- of the black hole—in the spring of 2014.
most distant Cepheid variables found close
gy of motion, heat and the acceleration of The researchers estimate the record break-
to the plane of the Milky Way. The paper
particles—which could produce a bright X- ing X-ray flares were produced about a hun-
announcing the discovery appears in
ray flare. Such magnetic flares are seen on dred times closer to the black hole, making
Astrophysical Journal Letters and is avail-
the Sun, and the Sgr A* flares have a simi- it very unlikely that the Chandra flares were
able online.
lar pattern of brightness levels to the solar associated with G2.
events. The stars appear to be associated with a
dwarf galaxy Chakrabarti predicted in 2009
“At the moment, we can’t distinguish
Lifting the veil on a dark galaxy based on her analysis of ripples in the Milky
between these two very different ideas,” said
Findings validate earlier prediction of Way’s outer disk. Chakrabarti’s earlier study
Haggard. “It’s exciting to identify tensions
galaxy’s location predicted the location of the dark-matter
between models and to have a chance to
A cluster of young, pulsating stars discov- dominated dwarf galaxy. Radiation emitted
resolve them with present and future obser-
ered in the far side of the Milky Way may by the Cepheid variable stars allowed her to
vations.”
mark the location of a previously unseen derive accurate distances and test her pre-
In addition to the giant flares, Haggard and dark-matter dominated dwarf galaxy hidden diction. Chakrabarti analyzed VISTA’s data-
her team also collected more data on a mag- behind clouds of dust. base of tens of millions of stars to find these
clustered Cepheid variables in the Norma
netar—a neutron star with a strong magnet-
A team, led by Sukanya Chakrabarti from constellation, all within one degree of each
ic field—located close to Sgr A*. This mag-
Rochester Institute of Technology, analyzed other.
netar is undergoing a long X-ray outburst,
8 www.AmateurAstronomy.com Spring 2015 Issue # 86
“These young stars are likely the signature of
this predicted galaxy,” said Chakrabarti,
assistant professor in RIT’s School of
Physics and Astronomy. “They can’t be part
of our galaxy because the disk of the Milky
Way terminates at 48,000 light years.”
Invisible particles known as dark matter
make up 23 percent of the mass of the uni-
verse. The mysterious matter represents a
fundamental problem in astronomy because
it is not understood, Chakrabarti said.
“The discovery of the Cepheid variables
shows that our method of finding the loca-
tion of dark-matter dominated dwarf galax-
ies works,” she said. “It may help us ulti-
mately understand what dark matter is made
up of. It also shows that Newton’s theory of
gravity can be used out to the farthest reach-
es of a galaxy, and that there is no need to
modify our theory of gravity.”
Rosette Nebula - Charlie Warren
VISTA’s infrared eyes allow scientists to world. In the 1930’s two of the first to study object usually seen only at infrared and radio
study unexplored regions close to the galac- these forming stars were George Herbig and wavelengths is, because of these special cir-
tic plane that are inaccessible to optical sur- Guillermo Haro. The structures with oppo- cumstances, visible in our amateur tele-
veys. Optical wavelengths cannot penetrate sitely directed jets ending in lobes visible scopes. An interesting consequence in this
the dust and gas in these regions. This next- through their interaction with the surround- case is, because of these dispersing winds,
generation sky survey helps scientists look at ing nebula were named after them: Herbig- the future star of HH1 may evolve to be less
the structure of the galaxy and distant stars at Haro objects. The nascent stellar object at massive and we could be witnessing a
low latitudes. Infrared surveys may help their centers is surrounded by a protoplane- process associated with brown dwarf forma-
resolve current discrepancies between obser- tary disc, with material accumulating within tion. On a clear spring evening take a look
vations and the current cosmological para- their cores until hydrogen fusion occurs from for this rare glimpse into star birth.
digm by giving us a more complete view of the heat and pressure. When they are unable
Rosette HH1: 06h 32m 20.79s, +04d 53m
the structure of the Milky Way, Chakrabarti to accommodate all the gas and dust, a pair
03.3s; magnitude 14.0
said. of bipolar jets are produced perpendicular to
Rector, ApJ Letters, December, 2003.
the accreting disc. With large reflecting tele-
“I decided to see if I could actually find the ApJ 659, p. 1373, April 20, 2007.
scopes I have glimpsed the outer lobes of
thing,” Chakrabarti said. “It was a difficult Dave Tosteson
several of these “HH” objects but, in almost
prediction to test because it was close to the Chisago City, Minnesota
all cases the central structures are not visible
plane, and therefore difficult to see in the [email protected]
because of a thick shell of obscuring materi-
optical. This new survey, VISTA, was able to
al. An exception exists within the beautiful
help us to lift the veil and see these young
Rosette Nebula (NGC 2237) in Monoceros,
pulsating stars.”
known as Rosette HH1.
Travis Rector of the University of Alaska,
Star Birth Anchorage, studied this unihorned ungulate
in 2003, and noted it as one of the few, or
possibly only, times this type of stellar for-
The process of star birth is one usually
mation called a protostar, and its jet, are
shrouded in mystery behind a veil of secrecy,
directly visible. The reason we are able to see
covered in layers of opaque dust and gas and
it appears that nearby stars surrounding HH1
hidden from curious eyes sensitive to only
use powerful stellar winds to disperse mate-
the visible light cocooned within.
rial normally hiding it from our view. In
Astronomers with instruments sensitive to
essence, we are witnessing a premature
radio and infrared wavelengths have been
delivery. At 14th magnitude, it is bright
able to study this process, but amateurs lim-
enough to be viewed in my 10 inch telescope
ited to visual photons are restricted, as grand-
and, from my home several years ago
parents at a human nursery, to meeting the
through my 15”
newborn after the initial process is conclud-
ed and the infant is presented to the rest of the
reflector, its jet was not difficult to spot. An
Spring 2015 Issue # 86 www.AmateurAstronomy.com 9
Practical Solutions and Guidelines for the
Merging Images in a Binoscope
.
by Arie Otte
T
he term binoscope is often images, one entire, physical half of the lenging. Specifically, when you move
reserved for a Newtonian tele- binoscope is slightly tilted in relation the ‘half-binoscope’ up and down,
scope with one mirror for each to the other half of the binoscope. In images are more prone to ‘de-merge’,
eye. Experienced observers claim that other words, the binoscope contains an since chances are that there is some
observing with a binoscope is superior entire telescope (consisting of the pri- remaining play in the system. Indeed,
to observing with a traditional ‘mono- mary, secondary and tertiary mirrors) in my hands there always remained
telescope’ that has a comparably large, that can move independently within residual play in the threaded rods I
but only one mirror. However, despite the space of the larger, encompassing used and that resulted in some separa-
this advantage, binoscopes are not binoscope mirror box. I built such a tion of the images when moving the
popular, presumably because they are set-up and it works very nicely scope up and down.
difficult to make. But is this true? (Picture 1, the right 'telescope' can
Merging of the images by tilting the
Probably one of the most difficult fea- move a bit). The main advantage of
primary mirrors
tures of making a binoscope is the this method is that the quality of the
I therefore opted for another procedure
need to precisely merge the images. images is not compromised by de-col-
that involves bringing together the
Here I present different aspects of limation, since no collimation of the
optical paths by means of slightly tilt-
merging images and provide practical primary mirror is involved.
ing the primary mirrors. This implies
solutions on how these can be ade-
Image 1: The right mirror box can that one moves the optical paths only,
quately addressed. This article intends
move independently from the rest of instead of an entire, physical, 'half-
to show that an ATM person who can
the binoscope. The arrows indicate the binoscope'. However, tinkering with
build a mono-Dobsonian telescope
ends of threaded rods that run through primary mirrors almost certainly
will also be able to build a good func-
the bottom of the larger binoscope mir- results in de-collimation of these mir-
tioning binoscope.
ror box. By slightly turning them, the rors. The result may very well be that
The two independent optical systems mirror box (and with that of course the one obtains well-merged images, but
of a binoscope have to produce two rest of the telescope that is built on it) these are at least slightly degraded
images that are both well collimated moves in relation to the other half of because the optical paths are out of
and accurately merged at the same the binoscope. By doing this, the collimation. Some binoscope owners
time. In principle, merging is nothing images can be merged. take this for granted and accept the de-
other than ensuring that the optical collimated images as a fact of life. It is,
The disadvantage of this approach is
paths of the two telescopes are brought however, very possible to achieve
that the system is mechanically chal-
together to create overlapping images. both: accurately merged images that
If all parts of the two optical paths
would be perfectly collimated and
aligned, if all the angles of the scope Image 1
would be perfectly square, if all mir-
rors (primary, secondary and tertiary)
and the focusers would be centered
perfectly, then the images would also
be well-collimated and merged. Alas,
no such thing as perfect exists, so
images will probably initially not be
perfectly collimated and will not be
merged. There are two main approach-
es to merge two well-collimated
images: 1) you move one half of the
binoscope in relation to the other half
or 2) you only move the two optical
paths in order to overlap each other.
I’ve followed both approaches.
Merging of the images by tilting an
entire half of the binoscope
In the first approach to merge the two
10 www.AmateurAstronomy.com Spring 2015 Issue # 86