June - Saguaro Astronomy Club

Transcription

Saguaro Astronomy
Club, Phoenix, AZ
Saguaro Skies
Volume 37, Issue 6
June 2013
The President’s Corner
If you're subscribed to the SAC
entirely, don't hesitate to come up
Board mailing list, you may have seen to the front of the room and tell us
a recent exchange of messages disabout it. Pictures and slides are great
cussing the emphasis on imaging in
if you've got them, but by no means
our member presentations. This
mandatory.
would seem to be a natural conseDon't forget that our July meeting
quence of two factors. First, there
is completely dedicated to member
are a number of active members of
presentations. If you've been up to
the club who have developed an insomething interesting, whether it
terest in imaging and acquired the
involves images or not, please conequipment and skills necessary to
sider sharing your work with us.
provide fantastic results, and second,
-- Mike -those fantastic results make for wonmailto:[email protected]
derful presentation material. I don't
think we want to discourage imaging
presentations. Since a substantial
fraction of our meeting agenda is allocated for show and tell, there's
plenty of opportunity for members to
present on other topics as well. So
http://saguaroastro.org
here's a call for presentations on all
topics related to
Quick Calendar:
our hobby. If
you're a visual
Fri/Sat, June 14/15: Grand Canyon Star Party North Rim link
observer, instrument maker, ob- Tuesday, June 18: ATM/Astro-Imaging Meeting
servatory builder, Friday, June 21: SAC General Meeting: Speaker, TBA
engaged in a sci- Friday July 19: SAC Gen. Mtg: SAC Member 10 min. Talks
entific pursuit,
(Prepare your talk & sign up with Jennifer Polakis, V. Pres.)
historian of astronomy or something else
Click the link below for a complete 2013 Calendar of events:
http://saguaroastro.org/webcalendar/month.php?date=20130601
Inside this issue:
Click Links to jump
Editor Notes/Events
(Rick Rotramel)
2
Call For Observations
3
Virgo/Canes Venatici (AJ
Crayon)
Bits and Pisces
6/7
30 Years Ago in SAC
25 Years Ago in SAC
10 Years Ago in SAC
8
And They Build Telescopes
11
9
10
(Rick Rotramel)
SAC Obsv: Fred.Meadow 14(Harshaw, Christ & Ray) 16
SAC Astro-Imaging
17
(Jimmy Ray)
On Being Double Minded 18(Richard Harshaw)
19
Special points of interest:

Spaceflight Trivia: page 2

SUCH-A-DEAL: page 4

Officers & Contacts: page 12

Meeting Location: page 12

Membership form: page 13
Header image © Tom Polakis
The stars of Scorpius setting over the
Estrella Mountains in Arizona.
Saguaro Skies
Page 2
Click logo to return to page 1
Schedule of Events 2013
Editor Notes
Hi folks, here’s your June
issue of the SAC newsletter.
Well, this month Last Call takes a break
due to some scheduling issues with June
being a pretty busy month and all. It will
come back in July with Virgo galaxies.
June brought us the Fredericksen
Meadow Star Party in Happy Jack. Some
SAC observers got up there for some great
skies and three of them give you a report of
the happenings there.
Jimmy Ray was able to take a few images
from Fredericksen Meadow and I present
them in the SAC Astro-Imaging feature.
Also take a peek at On Being Double
Minded and all the rest of the stuff.
Here’s hoping you all enjoy,
SAC Meetings
June 21, 2013
July 19, 2013
August 16, 2013
September 20, 2013
October 18, 2013
November 15, 2013
December (14?) TBA
(Holiday Party)
ATM / Astro-Imaging Mtgs.
On the Tuesday prior to the SAC Meetings
Tuesday, June 18, 2013 at 6:00 PM
@ Paul Lind’s shop ([email protected])
Rick Rotramel, Editor
Spaceflight Trivia
Can you name the mission involved in this
picture below? (see answer on page 5)
Major Star Parties
Grand Canyon North Rim
Sat/Sat, June 8-15, 2013
http://saguaroastro.org/content/2013GrandCanyonStarPartyNorthRim.htm
All Arizona Star Party ( EVAC )
Fri/Sat, October 4/5 ? (TBA)
Antennas Schwaar-Gaze
Fri/Sat, November 1/2, 2013
http://saguaroastro.org/content/db/antennae-handout.pdf
© NASA
Page 3
Saguaro Skies
Call For Observations
By AJ Crayon
At the last minute I decided to make a change on the
month of July’s observing list. What we will do is observe
some of the brightest barred spiral galaxies in Virgo to see
what they look like in our telescopes. Yes we know what they
look like from the myriad of pictures taken by SAC imagers as
well as those around the country and planet, but what do
they look like in our telescopes. Can you see the brighter
middle or the bar? What about the spiral arms? Most will be
described as bright and large and are in the Herschel 400 list,
so this kind of description can be left off. So here’s the list in
right ascension order. That will start us with NGC4216, which
is on the SAC Best of the NGC. It is edge-on and has a brighter
middle. Question is how much can you see? Second galaxy is
M 61 or NGC4303. It has had 3 super novae since 1926 and
NGC4301 is in the field. Now move on to NGC4527. This one
has quite a bit of detail in the middle. How much can you
see? While speaking of how much can you see have you been
able to see the spiral arms as they wind around the bar?
Don’t forget this on the remaining galaxies. The S-shaped
spiral NGC4535 follows. Along with quite a bit of detail in the
middle, it is elongated in a position angle of 0° or due north.
Now one of the brighter galaxies is M 90. It is elongated
about 2:1 but what’s the position angle? Do you notice anything different about this one that makes it stand out from
the others? Now another of the brighter ones and last of the
Messier entries is M 58. It is called a fine compact spiral.
How much do you agree or disagree? This next one,
NGC4654, seems to have something questionable about the
middle. What do you see here and it isn’t the 3 stars nearby?
The fairly round NGC4654 is next. How much can your telescope resolve - the brighter middle, the bar, spiral arms?
Take a look at the roundish NGC4699 and see if you agree.
The coarse spiral NGC5068 follows. It is listed as irregularly
round but does this have to do with the coarse part? Note
that NGC5087 is in the field. Again, another reminder, that
we should be trying to determine how much of the spiral
arms we can see and not just these beautiful galaxies. Here’s
another fine s-shaped double arm spiral - NGC5247. Checked
my observing list for this one and it hasn’t been seen so I’m
looking forward to this one not to mention all the others.
Continue with NGC5364. The description indicates it is round
but the dimensions don’t support this. Which description
best suites your observation? This galaxy is also listed as peculiar with a reference to a small bright nucleus in a smooth
center with dark matter. Dark matter? Finally this last of the
bright barred gems is NGC5746. It is very elongated, almost
edge-on, at almost 6:1. In addition to seeing the spiral arms
how much of the brighter middle did you see?
OK that’s it but there are a few comments that need to
be passed along. If you observe these spirals in right ascension order, the order in which they were described, your telescope will slew over 100°. That’s a lot but not nearly as much
as if they were viewed in increasing magnitude order. Here
the slew will be over 240°. But, if you are crazy enough to try
this here’s the list in increasing magnitude order - M90,
NGC4699, M61, M58, NGC4216, NGC5247, NGC4535,
NGC5068, NGC5746, NGC4527, NGC4654 and NGC5364.
Finally something reasonable – the shortest order. Using this
sequence you will slew your telescope less than 90°. So this
list is shortest order NGC5247, NGC5068, NGC4699,
NGC4527, M61, NGC4535, NGC4216, M90, M58, NGC4654,
NGC5364, NGC 5364 and NGC 5746. To determine the distances took my computer 22 minutes and checked some
439,084,801 combinations. Don’t know about you but I can’t
wait to check out these magnificent barred spiral galaxies.
After having reviewed constellations done in the past it
turns out there are a number of bright galaxies in Canes Venatici that haven’t appeared on our list, so let’s give this a try
for August. We start in the northwest section with NGC4218
the faintest of this bunch. The next two galaxies are members of the Best of SAC and Herschel 400 lists. So expect
them to be on the bright side. The first of the duo is
NGC4449 I’d call this one bright and large but the SAC database indicates something funny about the middle. What do
you see with this one? NGC4490 is next and appears to be
disrupted by our next selection. NGC4485 is just that one. In
addition to your observation please note the position and
distance from the prior entry. Now we move to a southerly
entry in the constellation. That turns out to be NGC4214 another entry in the two aforementioned lists. It has also been
mislabeled as NGC4208 so be careful if you do some research
on this one, which is also a member of the Herschel 400 list.
Our next entry will be somewhat of an interesting challenge.
It starts with NGC4395 that has a low surface brightness and
3 faint HII regions that form a trapezium. Include these 3
regions in your observations. They are NGC4399, NGC4400
and NGC4401 be sure to list their positions and distances.
This system should be fun for me also, as it hasn’t been observed – at all! Now we move to the southern part of the
constellation to M3, which I think doesn’t need much of an
introduction. Finally, the last entry is at the very western
edge. It is NGC5383, a reasonably bright and large galaxy.
There you have it, so have at it and let’s hope for lots of clear
skies to make up for the cloudy ones.
Volume 37, Issue 6
Page 4
SUCH-A-DEAL
18” Classic Obsession Telescope for Sale
Purchased new in 1997 with Galaxy optics. Selling to move to a different
scope. Originally the mirror tested with a
Strehl ratio of 0.955 (Fringe Centers) /
0.961 (Uniform Grid) and a RMS value of
0.034. It was refigured in 2000 by Swayze
Optical to remove some zones. The mirror
star-tests very well. All mirrors were recoated in the last 9 months by OMI (IBAD96 Coating process). The woodwork does
show cosmetic finish issues. There are numerous upgrades to the scope. Asking
$3,200 or best offer.
Contact me at 602-291-3508 or e-mail me if
you want details.
[email protected]
Your Ad Here
SUCH-A-DEAL
Ads placed here are free to SAC members. SAC
is not responsible for the quality of the advertised items.
If you wish to place an ad here to sell your
telescope or astronomy related items, contact
Rick Rotramel at: [email protected]
18” f4.5 Telescope Main Photo from Obsession Website
Volume 37, Issue 6
Page 5
Spaceflight Trivia Answer
40th Anniversary of Skylab
http://www.nasa.gov/topics/history/features/skylab.html
Launched aboard the last of the Apollo-era Saturn V rockets on May 14, 1973,
the uncrewed Skylab became America's first space station. The station almost
immediately developed technical problems due to vibrations during liftoff when a
critical meteoroid shield ripped off, taking one of the craft's two primary solar
panels with it. Engineers in mission control maneuvered Skylab's secondary solar
panels to face the sun to provide as much electricity as possible. Because of the
loss of the meteoroid shield, however, this positioning caused workshop temperatures to rise to 126 F. Meanwhile, in an
intensive 10-day period, NASA engineers developed procedures and trained the crew to make the workshop habitable. At the
same time, engineers "rolled" Skylab to lower the temperature of the workshop.
On May 25, the first crewed mission, launched to rendezvous with the station, bringing with it the first crew to inhabit
America's space station. And, after the crew made substantial repairs, including deployment of a parasol
sunshade that cooled the inside temperatures to 75 F, the workshop was made fully operational by June 4.
The first crew consisted of Commander Pete Conrad, who also commanded Gemini XI and Apollo 12, and
piloted Gemini V; Pilot Paul Weitz, who later commanded the maiden voyage of space shuttle Challenger in
1983 and became deputy director of NASA's Johnson Space Center in Houston; and, scientist and naval
flight surgeon Joe Kerwin.
In all, the three Skylab crews conducted 16 biomedical experiments, obtaining information on humans'
adaptation to microgravity for the first time. Kerwin stated: "It was a continuous
and pleasant surprise to me to find out how easy it was to live in zero g, and
how good we felt."
Skylab's achievements are a summary of the accomplishments of many ground-based teams, as
well as its three separate crews. By deploying the parasol-type sun shield through Skylab's solar
scientific airlock and later releasing workshop solar array wing No. 1 during a spacewalk, the first
crew made the remainder of the mission possible. During another spacewalk, the second crew
deployed another sun shield.
Skylab I
Crew: Charles C. Conrad Jr., Commander; Paul J. Weitz, Pilot; Joseph Kerwin, Scientist
Launch Date: May 25, 1973, Launch Time: 9:00 a.m. EDT, Launch Vehicle: Saturn 1B, Launch Pad 39B, Kennedy Space Center
Recovery Date: June 22, 1973, Recovery Time: 9:49 a.m. EDT, Distance Traveled: 11.5 million miles; 28 days, 49 minutes
Mission Highlights
First manned mission. The crew rendezvoused with Skylab on the fifth orbit.
After making substantial repairs, including deployment of a parasol sunshade that
cooled the inside temperatures to 23.8 degrees C (75 degrees F), the workshop was
in full operation by June 4. In orbit, the crew conducted solar astronomy and Earth
resources experiments, medical studies and five student experiments. The mission
completed 404 orbits and 392 experiment hours, as well as three EVAs totaling six
hours, 20 minutes.
Mission Achievements
Installed a solar shield "parasol" from scientific airlock. Released solar array
wing on EVA. Doubled previous length of time in space.
© NASA
Double Exposure: Left, Skylab on Saturn V at Pad 39A.
Right, Skylab I on Saturn 1B at Pad 39B, 1 1/2 miles away.
Page 6
Saguaro Skies
Bits and Pisces
The May Meeting Speaker
Editor’s note, Here’s Mike’s post to SAC-Forum:
[sac-forum] Links from SAC Presentation Tonight
From: Mike Wiles <mikewilesaz@xxxxxxxxx>
To: SAC-Forum@xxxxxxxxxxxxx
Date: Sat, 25 May 2013 00:09:59 -0700
Hello all,
Thanks for the patience and attention to listen to my
presentation tonight. I appreciated the large number of
questions and healthy dialogue that we had going at certain points. As promised, here's the list of additional resources that I had in my presentation.
Mike Wiles at the SAC podium. Photo, Rick Rotramel
Mike Wiles of SAC, amateur astronomer and a
fine astro-imager, spoke to SAC about his science
of and work of astrophotography.
A well spoken and thorough talk, one could
come away with a solid understanding of the work
it takes to put together a fine astro image.
Mike gave a well explained trip through the
steps with reasons why you should and shouldn’t
do things, all learned through experience.
He gave out many tips and links (posted later
on SAC Forum) to fully explain how one does all of
the steps to put together an image that will impress everyone.
Mike also explained why he purchased the particular equipment for his setup. His learning curve
gave him experience to choose the right stuff to
carry out the process. I guess it always comes to
that, you learn as you go. It seems Mike has
learned much in his short time doing this stuff. One
is impressed indeed as to his success in such a
short time at doing this.
Of course I should also mention that Mike has
spent many hours at the University of Arizona’s
Mount Lemmon SkyCenter, as a Program Leader
there. Amazing stuff! Here’s the link:
http://skycenter.arizona.edu/about
Periodic Error Correction:
http://ccdware.com/products/pempro/
Autoguiding:
http://acp.dc3.com/McMillanAutoguiding11-2005.pdf
Autoguiding Parameters:
http://ccdware.com/resources/autoguidercalcv4.cfm
Subexposure Length: http://ccdware.com/resources/
PixInsight: http://pixinsight.com/
Best PixInsight Tutorials:
http://harrysastroshed.com/pixinsighthome.html
More PI Tutorials: http://www.werbeagentur.org/
oldwexi/PixInsight/PixInsight.html (copy & paste this last
part of the link in your browser to the end of url link above)
More PI Tutorials:
http://www.deepskycolors.com/tutorials.html
Extensive PixInsight Help: http://pixinsight.com/forum
If I can help anyone grasp this stuff by sharing some of my
own experience, I'm more than happy to do so. Thanks for
being a great group and giving me the time to present this
evening.
Mike
Mike’s images: http://www.astrobin.com/users/MikeWiles/
Volume 37, Issue 6
Page 7
Bits and Pisces (Conclusion)
Minutes of the May 24, 2013 General SAC Meeting
As recorded by Acting Secretary Darrell Spencer (due to the absence of Secretary Richard Harshaw)
President Collins sounded the gavel at 7:30 sharp.
We had one new guest.
* There is a Novice Info web page that may be found at:
http://www.saguaroastro.org/content/novice.htm
The Treasurer (Dwight Bogan) reported a balance
of $4280. Dwight also had some officer badges for
new officers.
The ATM Group summary discussed 3 scopes and a
camera that were tended to.
The 50-50 raffle didn't happen. It became a 100-0.
(Chris forgot tickets). It is believed he ended up
with $56 in straight donations at night's end.
President Collins announced that the July SAC
meeting will be an "All Member Show-n-Tell".
Jack Jones had a nice slide show about this year’s
Thunderbird Park star party.
Rick Tejera did a Messier Marathon run-down with
awards and plaques. He again lauded A J Crayon
(who was present) as having had big shoes to fill.
Just before break, Tom Polakis showed sky charts
of the weekend's Venus/Jupiter/Mercury conjunction. He mentioned that it might be a good time to
go check it out during the break.
It was.
After the break, Dr. Mike Wiles had a very nice,
detailed presentation on the technical’s (noise, acquisition, guiding, processing) of deep sky imaging. Lots of interest, questions and discussion. Nice
presentation with humorously animated
slides. Went over very well.
At 9:45, the meeting adjourned, with the obligatory announcement on heading over to the greasy
spoon.
SAC members check out the planetary conjunction during the break. Photo, Rick Rotramel
Saguaro Skies
Page 8
Where we going today
Mr. Peabody?
© Peabody and Sherman, 'Rocky and Bullwinkle' Pictures
The WABAC Machine!
30 Years Ago in SAC
Page 9
Saguaro Skies
25 Years Ago in SAC
Page 10
Saguaro Skies
10 Years Ago in SAC
Volume 37, Issue 6
Page 11
And They Build Telescopes
By Rick Rotramel
Apogee U16 CCD Camera Filters Installation
The monthly SAC ATM (Amateur Telescope
Making)/Astro-Imaging meeting of May 21, 2013
was attended by Paul Lind, Lynn B, Matt L, and me.
Matt brought in his U16 CCD Camera for Paul
to try out on his Astrograph. The unit contained a
filter wheel that needed the filters installed.
Astro Chair Anti-Hand Pinch Mod
Last month I brought in my astro chair that I
recently purchased from Mitch Prause that I had
used at the Messier Marathon. The first time I
went to move the chair I pinched my hand between the two halves of the chair, ouch! Soon,
Lynn comes up with the solution. Simply place a
piece of wood inside the two halves at the top of
the chair to lock the chair apart. I found a 7/8”
dowel and held it there with a U-Bolt and it works!
Another problem solved at the ATM meeting.
So this month I then
brought in a 4 foot piece
of 7/8” birch dowel to be
cut down to 12” in length
to be the piece needed
to do the job. I measured
Paul cutting the 7/8” x 12” dowel
and marked a 12” piece
and Paul proceeded to cut it on his sabre saw table. Lynn asked Paul to cut another one for his astro chair so that he could modify his chair, and so
he did that.
I then installed the
5/16” U-bolt and the 12”
piece of 7/8” dowel onto
one of the cross supports near the top of the
back half of the chair.
Delicate is the operation
It was interesting watching all this unfold. Matt had
opened up the bags of filters and was handing them off
to Paul to install in the filter wheel. About three filters
later, Matt stumbles across the instructions for the installation of the filters. “Place filter with shiny side up
as indicated by a arrow mark on the side of the filter.”
Matt gently places in the blue filter
Paul secures the green filter
So then Paul had to flip one of the filters over which
had been installed upside down.
Then Matt fired up the
software on his laptop to
show Paul how to run the
camera and filter wheel. It
will be interesting to see
Paul’s first results shooting
with this camera.
Matt explains the software
Epilogue
The dowel and a U-Bolt clamp
So when travelling,
you just loosen the wing
nuts and move the
dowel to the other side
of the block and tighten
the bolt to secure it.
The dowel doubles as a handle
A view of the filter wheel innards
That’s all for this month, see you next time.
Remember, if you have a “need” for your telescope, or want to talk astro-imaging, come over to
Paul Lind’s shop at the next SAC ATM/AstroImaging meeting on the Tuesday evening before
the SAC general meeting and join in on all the fun.
Paul will post the date on the SAC-Forum list. Hope
to see you there. It’s a fun time for all.
Volume 37, Issue 6
Page 12
OCCULTATION INFO
2013 SAC Officers and Contacts
Board Members
President
Vice-President
Treasurer
Secretary
Properties
Wayne Thomas has asteroid occultation info
for the greater Phoenix
Area:
Mike Collins ([email protected])
Jennifer Polakis ([email protected])
Dwight Bogan ([email protected])
Richard Harshaw ([email protected])
Lynn Blackburn ([email protected])
Non-board Positions
Novice Group Leader
Newsletter Editor
Webmaster
Public Events
ATM Group
Imaging
Deep Sky Group
Sketchbook
[email protected]
Steve Dodder ([email protected])
Rick Rotramel ([email protected])
Peter Argenziano ([email protected])
Jack Jones ([email protected])
Paul Lind ([email protected])
Al Stiewing ([email protected])
A. J. Crayon ([email protected])
Rick Rotramel ([email protected])
Meeting Location: Grand Canyon University is located at 3300 W.
Camelback Rd, Phoenix, AZ We meet in Fleming Hall, Room 105,
7:30 PM to 10:00 PM
Gene Lucas has Lunar
Total and Graze Occultation info:
mailto:[email protected].
com
SUCH-A-DEAL
Ads placed here are free to SAC members. SAC is not responsible for the
quality of the advertised items.
If you wish to place an ad here to sell
your telescope or astronomy related
items, contact Rick Rotramel at:
[email protected]
Your Ad Here
See ad: page 4
Contacting This Issue’s Authors
If you wish to write to an author in this month’s issue, complaining that they don’t
know what they are talking about or that they utterly dazzled you with their wordsmith skills, contact them by sending your message to the editor of Saguaro Skies,
Rick Rotramel, at: [email protected]
I will then forward your questions, comments or carping to the author who may
(or may not) reply.
Page 13
Saguaro Skies
Volume 37, Issue 6
Page 14
SAC Observing:
June 2013 Star Party at Fredericksen Meadow, Happy Jack, Arizona
Observing Event Reports by: Richard Harshaw, Bob Christ & Jimmy Ray
Awesome Skies and Glitches at FM
By Richard Harshaw
As Garrison Keillor might say, “It has been a quiet week in Lake Wobegon.” Except I need to reword it to, “It has been a frustrating week at Meadow Fredericksen.”
Oh, not because of the skies. They were their usual awesome Arizona show-off skies! Our worst night of the week was a 7/7
night, and the best an 8/8.
Nor because of the chiggers and gnats (the population of which probably exceeded the number of red dwarfs in the Milky Way).
Nor because of the unusually cold night temperatures (dipping into the upper 20’s one night, making it an odd fact that we got
more warmth from the CBR than from our own earth).
Nor because of the great gang of people who were there (in and out) for the week—Steve Coe, Lynn Blackburn, A J Crayon, yours
truly, Darrell Spencer, Jimmy Ray, Bob Christ, Phil Scow, John Fox, Bob ???, and a young chap I had never met but stayed only
part of one night. Nor because of the guests we had from the Clint’s Well general store on Wednesday night (5 people who were
blown away by what was always over their heads every night).
No, it was frustrating because of technical difficulties out the wazoo. First, Bob ??? (and I am sorry I don’t have his last name)
had to leave early because of chest pain. I don’t know whether the altitude was the culprit or if he was on the verge of a heart
problem, but I do hope he is alright.
It was frustrating because even the amazing Steve Coe had problems with the power cord for his Sky Commander, said cord producing intermittent power (and hence multiple frustrations) as the night wore on.
It was frustrating because Darrell Spencer’s new hand paddle for his C-GEM mount did not work and his old one having an intermittent display.
It was frustrating because John Fox was halfway through setting up his excellent equipment on an Astro-Physics pier when he
discovered he left his dovetail plate bolts at home and none of us had suitable substitutes (so poor John spent the night in a chair
near Steve Coe and I, sharing our views and chatting through the night).
It was frustrating because Jimmy Ray actually blew out his Sky Commander (and in the same way I blew out mine 2 years
ago). Here’s a tip for you Sky Commander fans. Do NOT lay a nylon tarp on the ground under your scope. As the night wears on,
you build up a tremendous amount of static electricity on your body and the tarp insulates you from the earth. Eventually, you
touch your mount to move to a new object and a spark occurs. It can be bright enough to cause night blindness for a radius of a
kilometer, and it also loves to fry the mother board on the Sky Commander. Therefore, I NEVER use a tarp under my scope any
more (and you can bet Jimmy won’t be doing so under his ever again either!). Steve Coe
was then worried because he had a nylon tarp under his Sky Commander equipped Dob,
but I don’t think a scope with a wooden frame would be a problem.
And finally, I found a loose dovetail plate on my CI-700 mount, and the usual remedy of
tightening the two Allen bolts that secure it did not work. The problem is apparently
deeper inside the mount itself. Oh well, a project for an afternoon day in an air conditioned
house!
All this reminds me of a friend in Kansas City who once drove 95 miles to a dark sky site to
observe with his 20-inch Starmaster Dob. It was dusk and he was assembling his beauty and
stopped at midpoint and swore several rather unprintable words. I asked what was wrong
and he said he forgot to bring the nuts that secure the truss tubes to the rocker box and
secondary cage. He promptly packed up and drove home.
Moral: When you go observing, don’t forget your nuts.
Volume 37, Issue 6
Page 15
SAC Observing: (Continued)
More about Frederickson’s Meadow viewing
By Bob Christ
Friday night, June the 7th was excellent, and Saturday night was outstanding. The transparency was 8 of 10 as proclaimed by Steve
Coe, and the seeing “wasn’t bad either.”
The two evenings I spent there comprised my first visit to Frederickson’s Meadow and first light for my new Explore Scientific 68°
oculars (34/24/16mm) and the sky cooperated beautifully. My long-awaited 24mm eyepiece was used 98% of the time and my
view of M8, using an OIII filter, was absolutely picture quality in monochromatic grayscale and the festoon-like features were simply mesmerizing. When viewing M51 in my C9.25”, I was finally able to see the arms using direct vision, and averted vision revealed the bridge to the galaxy M51 is scavenging.
Four commercial British pilots, three of whom are English and the fourth a Scot, are in the States for flight training and made the
trek to the Meadow for a Saturday night treat to the sky.
The Scot, degreed in Astronomy, is an amateur astronomer and astrophotographer. His penchant is DSOs, and the reference book
he uses is titled: “Nebulae and How to Observe Them”. When Steve introduced himself as the author I thought the fella would
pass out. It’s truly a small world.
Showing objects to the English fellows was like conducting an outreach program as they are astronomy neophytes. Not so for the
Scot, and he was amazed with the views from our pristine sky, a sky he is not blessed-with in Scotland.
While the chiggers can be a problem, I managed to remain unscathed by using a combination of sulfur powder (thanks Dick for the
tip) on my socks and 40% and 100% DEET spray applied to other key areas.
As an aside, the general store at Clint’s Well is a wonderful throwback to days long gone by: it’s a gem. From my perspective it’s a
must-see.
Rogue's Gallery: Darrell Spencer, Dick Harshaw, ??, Jimmy Ray
Steve Coe and Bob Christ homesteading
Photo, Bob Christ
Photo, Bob Christ
Volume 37, Issue 6
Page 16
SAC Observing: (Conclusion)
View of Jimmy’s Fredericksen Memorial 5” f5 Refractor
Photo, Jimmy Ray
View of the Meadow before the Saturday night crew arrived
Photo, Bob Christ
Closer view of the scope
Photo, Jimmy Ray
View from Jimmy Ray’s set up at the meadow
Photo, Jimmy Ray
View of the Identification Plate on the scope
Photo, Jimmy Ray
View from Jimmy Ray’s home away from home at the meadow
Photo, Jimmy Ray
Page 17
Saguaro Skies
SAC Astro-Imaging: (Recent Astro-Images liked by the editor.)
Milky Way Galaxy, Sagittarius/Scorpius area
© Image by Jimmy Ray
6-7-13 Fredericksen Meadow; Happy Jack, AZ
3 minute exposure, ISO 800
28mm f4.5, Canon EOS DIGITAL REBEL XTi
The Summer Triangle, Vega, Deneb & Altair
Cassiopeia
Page 18
Saguaro Skies
On Being Double Minded
By Richard Harshaw
June
(To view before the meridian, observe in May; to view after the meridian, observe in July. This column is set to place
the stars in convenient locations at 9:00 pm LT.)
With the arrival of June, we find ourselves once again approaching the plane of the Milky Way. So expect the double
star counts to increase over the next several months.
The Featured Pairs
Both of this column’s featured stars this month are located in the constellation Boötes.
Xi Boo ( Boo, STF 1888)
Xi Boo is a complex system of six Main Sequence stars located
at 1451.4+1906. The primary is virtually a twin of the sun being
a G8 V star. The companion is a K5 V dwarf. In 1999, Soderhjelm calculated an orbit for the AB pair, resulting in a period of
151.6 years, a semi-major axis of 4.94 seconds, and angle of
inclination of 139°, and a very elliptical orbit with a value for e
of 0.51. All of the other companions appear to be optical background objects. Here is a plot of Soderhjelm’s orbit:
(The plot is printed upside down to match the view in a telescope.) Yet Hipparcos obtain parallax is for A and B that suggest that they are very far apart (22 light years for A and 1,623
light years for B). The proper motions for the A and B stars are
also very different, A being listed as (+159 -136) and B as (+90
-147). Given the different parallax is and proper motions, I
have to seriously challenge Soderhjelm’s orbit.
The primary shines at 4.54 magnitude while star B is at 6.81. The other stars are as follows: C 12.60, D 9 .60, E 8.65,
and F 9.20. I saw all the primary star as yellow and the B star as pale orange. All of the other companions I saw as
white.
Kappa Boo ( Boo, STF 1821, Asellus Tertius)
Bayer coined the name for Kappa but we have no idea what he meant by it.
This beautiful pair, composed of a 4.53 magnitude A8 IV primary and a 6.62 magnitude F2 V companion lying some
13.5 seconds away in position angle 235° (2007), is located at 1413.5+5147. Both stars share the same proper motion
and while Hipparcos shows them to have slightly different parallax is, there is enough error in the measurements to
easily allow the two stars to be at the exact same distance.
In 2006, Kiyaeva solved the orbit giving a period of 6,675 years with a semi-major axis of 11.4 seconds. The inclination
to our line of sight is 100° and the eccentricity of the orbit is 0.50.
Page 19
Saguaro Skies
Here is a plot of the orbit. Needless to say, this orbital solution is very sketchy at this time.
(The plot is printed upside down to match the view in a telescope.)
I saw the primary as a beautiful deep yellowy gold and the
companion looked orange to me even though it is an F2
star. The orange could be a contrast effect generated by the
intense gold of the primary.
Surprisingly, both of the stars you can see in your telescope
are spectroscopic binaries. Each pair of stars tips the scales
at 4.2 solar masses and 3.6 solar masses respectively.
In addition, the primary is a Delta Scuti variable, a class of
young pulsating variables. These stars have masses in the
range of 1.5 to 3.0 solar masses and generally have spectra
that range from A3 to F6. They have very small variations in
brightness, usually running from 0.012 0.4 magnitudes with
very short periods (eight hours or less).
This pair is also a member of the Sirius Group, a group
which includes not only Sirius and Kappa Boo, but also Beta
Aurigae, Alpha Coronae Borealis, Beta Crateris, Beta Eridani
and Beta Serpentis. All of these stars seem to be moving
through space as a group and share chemistry.
The Other Fine Pairs of June
I list the rest of the outstanding double stars for June in
the following table:

June - Saguaro Astronomy Club

Transcription

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