At the January Meeting
Don Surles brought the meeting to order at 7:15 with 25 members
and guests attending.
2nd Annual Mid Atlantic Mirror Making Seminar
Our 2nd Mirror making seminar is all set for March 1-3, 2002.
This year, we have added a project to assemble a solar prominence
scope under the supervision of the developer Dave Groski. Doug
Miller will assist those wishing to understand the basics of hacking a
webcam for astro photography.
Assistance in mirror grinding, polishing, figuring and testing will
be provided by Steve and Bruce Swayze of Swayze Optical and several experienced
mirror makers from Delmarva Star Gazers.
See Club Web page for more details.
Constellation of the Month: Orion (oh-RYE-un)
This constellation was presented by Ron Tatman.
Mythology - Almost every culture has lore surrounding Orion.
Ron chose the Egyptian Mythology which, if nothing else, is the oldest
and most intriguing. In the Egyptian mythology, Orion is Sahu and
represents the incarnation or soul of Osirus, King of the Dead. Always
accompanying the constellation Orion is the star Sirius who represents
the soul of Isis. Isis, the
second most important deity is the sister/consort of Osiris and the
Protector of the Dead. This mythology played an important part in the life
of the Pharaoh Khufu and the great pyramid. The ancient Egyptians
believed that Osiris and Isis were embodied in the constellation Orion
and the star Sirius, respectively. Khufu wanted to make sure he joined
these deities when he died. When he had the great pyramid built,
it was oriented with the cardinal points of the compass (i.e. North,
South, East, & West) as were most important edifices of the time.
In addition to this, shafts were constructed from the burial chambers
to the northern and southern walls of the pyramid. The angle of elevation
of the southern shaft was 44o and would show the place of the
gods in Sirius or Orion’s belt in transit. The angle of elevation of the
northern shaft was 31o and led to the pole stars. Since
the pole stars would never rise nor set and were always visible, they were
deemed indestructable.
None of these shafts were straight enough to actually see the stars
from the burial chambers but they could provide access for Khufu.
Astronomy-Ron took an equally innovative approach to the astronomy
portion. Since Ron has an interest both in radio astronomy and the birth
of stars, he discussed the role of radio telescopes in studying star formation,
so much of which occurs in Orion and the great nebula.
Paradoxically, star formation begins in a bitter cold environment (
10-20o K) which causes interstellar gases and dust to become
molecular and group together. Carbon monoxide ( CO ) and Hydrogen ( H2
) are the most comt the Janumon compounds in these molecular clouds. To
radio astronomers, the CO is the guide to structure and motion, since CO
resonates at specific frequencies and produces radio waves which can be
studied. The deep cold also causes clumping.
This clumping continues with ever increasing densities and star formation
begins. Since these dense clumps emit no visible light, we need Infra Red
and Radio Telescopes to study them. These clumps form cores of 104
solar masses. The cores then fragment into new clumps of 10-50 solar masses.
These fragmented clumps then form protostars in a process that takes 10
million years. As the protostars warm, they become infra red sources.
A number of these protostar candidates have
actually been found by the Hubble telescope in the Orion Nebula.
Once the protostars begin to burn hydrogen, they form strong stellar winds
along their axis of rotation. These winds may be collimated into a bipolar
outflow which is readily seen with radio telescopes. This stage of
the star’s development is called the T-Tauri phase named after the original
spectral G type prototype.
It is characterized by strong stellar winds, high surface activity
and variable light curves. T-Tauri stars are found surrounded by
the dust and gases that spawned them. The trapezium star cluster
in the Orion nebula is such an example.
Since T-Tauri stars are transitional, they are not guaranteed
full starhood. Depending on their mass, they can become a g-type
star like our Sun or they can fizzle out as a Jupiter type brown dwarf
eventually degenerating to a lifeless black dwarf.
Ron concluded his presentation with the usual stats on the important
stars and objects in Orion.
Program- The Mason Dixon Line
Bob Mentzer presented this program which dealt with and led to the
survey and creation of the Mason Dixon line. The problem first arose
in a conflict between the Penn family of Philadelphia and the Calvert family
of Maryland. In 1653, King Charles I had given George Calvert what
was then the Colony of Maryland. 50 years later, Charles II gave
William Penn the colony which would later become Pennsylvania as well as
land containing what we now call the Delmarva Peninsula.
Confusion arose many years later when it was discovered that the boundaries
didn’t match, particularly the southern border of Pennsylvania which was
supposed to be the 40th parallel.
In 1750 the British court ruled that the boundary between Maryland
and southern Pennsylvania should be a line 15 miles south of the
southern boundary of Philadelphia. The 2 families agreed to have
the new boundary surveyed, but had to go to England to find surveyors up
to the job.
Enter Charles Mason and Jeremiah Dixon in 1763. Mason was an astronomer
from the Greenwich observatory and Dixon, a skilled surveyor.
Before taking on their major task, it was necessary to survey the north-south
line on the Delmarva peninsula that divided the Penn and Calvert lands.
After that, they located the point 15 miles due south of Philadelphia.
At this point Bob brought us up to speed on the state of the art in 1763
for measuring celestial angles. Since there would be no horizon lines
available, the angle measuring was done using a 6 foot zenith sector.
The zenith sector is analogous to a plumb bob with a telescope measuring
a star’s declination from the zenith.
For example, if the star delta Perseus was over the 40th parallel at
a certain time and it measured 1o declination
with the zenith sector, your distance from the 40th parallel
would be 1o or 67 miles.
Back in Greenwich under ideal conditions, the accuracy of measurement
was 1/10 of an arc second
but the accuracy of their zenith sector was only .2 arc seconds .
Since the beginning of their east-west line would be west of Philadelphia,
they had to begin their measurements to the east of the east-west line.
The exact point was in the middle of Mr.Alexander Bryan’s plantation house,
and an observation post was built in his front yard. From there
the survey moved west following the line of latitude 39 degrees, 43 minutes
and 17.6 seconds North. Bob then reminded us that the shortest
distance between 2 points on earth is a great circle whereas
latitude lines on earth are not the shortest distance. A great
circle is the line formed on earth, by the intersection of a plane passing
thru the earth’s center. This means that a great circle line superimposed
on a latitude line will actually cross the longer curved latitude line
twice. The survey therefore consisted of making star measurements
with the zenith sector every 12 miles while making constant corrections
to convert the great circle survey lines to latitude lines.
Surveying in the wild forests was difficult and slow and not
without all kinds of pit falls. One of the most dangerous was
the Indians, particularly the Shawnees, near the western end
of the line. To avert this danger, the group hired 14 Iroquois as escorts.
The Iroquois prestige and influence among the Indian nations kept the party
safe from the more hostile tribes to
the west. However at a point 36 miles short of the 233 mile goal,
the Iroquois escort told them to go no farther and on October 9, 1767,
the survey was finished. The horizontal black bar on the map below
is the final Mason Dixon line.
The vertical line is the border between Delaware and Maryland
and is called the Transpeninsular Line.
Bob Mentzer concluded his presentation discussing how symbolic
the Mason Dixon line was to become, especially in terms of Slavery and
Freedom and even in the American Civil War still a hundred years away
.
From the President’s Desk...
January 19, 2002 Well, how much Enron stock did you have in your portfolio?
Have you done all your K-Mart shopping? Where is Osama? Where
will Ashcroft's and Rumsfeld's terrorists attack next? What kind
of attack will it be? Is Arthur Andersen your accountant? Do
you have any of those choking vodka pretzels? Are the Taliban prisoners
in
Guantanamo being mistreated or treated to a Caribbean vacation?
How's your love life?????? Filed your TAXES? Where is
your snow shovel? Jeez!! We could all lose our minds if television
ruled. Fortunately it only 'entertains' us with news and Hollywood's
interpretation of history and the future or what could possibly happen
sometime somewhere by somebody in an Ashcroft fantasy future. However,
we are amateur astronomers and we KNOW there are UNIVERSE forces
that have not and will not be influenced by anything anyone currently on
Earth has done or will do. So, we have a type of life
governor that provides us with a teflon shield from the everyday flotsam
spewing through our TV's, computers, newspapers, and the movie screen.
We are realists; we understand the sun will rise tomorrow morning and five,
fifty, a hundred or five hundred years from now the most important,
critical news stories of today will not command even a paragraph in the
history books of tomorrow. So, we go about our daily activities,
doing the best we can for family, self, and community and we ignore those
things that are outside our realm of control and we are happier for having
done so. So much for current events; leave
them to the politically gifted.
Now to astronomy. This is the time when we should all go out
and look for the winter sky jewels. Saturn's rings are "wide open", ie,
Saturn is tilted so that we have a superb view. And Saturn is overhead
so that we are looking through a minimum of atmosphere. Jupiter is
also a jewel; it is about as close to us as it gets and is overhead.
You must look at the Orion Nebula before it reaches the meridian; it is
high in the early evening sky and is much prettier to me before it reaches
the southwestern portion of the sky. Is naked eye astronomy your
preference? Then look for the Winter Hexagon. Start with Capella
(Auriga), go to Aldebaran(Hyades), then to Rigel (Orion), to Sirius (Canis
Major), then to Procyon(Canis Minor), to Pollux (Gemini),
and back to Capella. Once you see the Hexagon, it will be as
easy as the Teapot in Sagittarius.
Binocular viewing is superb because the winter sky is so transparent
and because the winter Milky Way (just to the east
of Orion through Auriga) is high above the horizon. Get your
star charts or planisphere, bino, scope, warm clothes,
gloves, and boots, a hot drink, etc, go out and see for yourself.
Be sure to see all the bright sights of the winter sky 'cause the dim,
dull, galaxy loaded spring sky is coming and will shove the winter sky
to the west and into the sun's glare.
Are you ready for the Mid Atlantic Mirror Maker's Workshop? I
hope so because we are gearing up for a fantastic weekend of amateur astronomy.
Check out our website for details. We have twelve mirror makers and
twenty prominence scope
makers plus the best talent in our hobby to guide us through the process.
And we have Delmarva Star Gazers as hosts for the event so you know we
will have some excellent food!
Following the MAMMW is the first five-day star party on the East Coast.
Delmarva Star Gaze VIII will begin Wednesday, April 10 and end Sunday,
April 14. Make plans now. Get your taxes filed so you
can stargaze without the burden of April 15 spoiling your time under the
Tuckahoe skies.
Have you considered serving as an officer of Delmarva Star Gazers?
Now is the time to make plans for the next election. Nominations
for officers will be taken at the May meeting and voting occurs during
the June meeting. Please give this some consideration; it is a commitment
but it can be very rewarding. We will begin our ninth year in April.
Do you have a concept of what this organization should or could be five
or ten years from now? We need energetic leaders to continue what
has been a wonderful journey so far We ave evolved into an organization
that many people find very comfortable. The Delmarva Star
Gazers must continue to evolve 'comfortably'; but we must continually
sharpen our skills and interests so that our offering accommodates as many
amateur astronomers as possible. That's where each of us has a responsibility
to improve Delmarva Star Gazers.
Have you shared your hobby with a friend, neighbor or child?
If not, why not? Be assured that everyone will not become 'hooked'
on astronomy but you will not know unless you offer to share
Who knows what kind of influence a view of Saturn, Jupiter, the moon, or
the sun will have on your guest! Go for it; you will be rewarded
greatly when the newbie utters that "WOW!"
Our first Saturday Morning Astronomy breakfast was a great success.
We had approximately twenty-five folks attend. Tom Brennan provided
a comprehensive presentation on "Life in the Universe" thanks, Tom.
Ron Zink and Lyle Jones did a great job cooking a breakfast of eggs, sausage,
bacon, grits, biscuits, sausage gravy, fruit, coffee, etc. Thanks,
Ron and Lyle. Also, many, many thanks to the volunteers who helped
clean up the kitchen. We will do this again; stay tuned for more
details.
K-Mart is now only $1.25 per share. Remember the stock market
advice "buy low, sell high"? This could be an opportunity to buy
low; a lonely opportunity! Why not go for the 'Blue Light Special'
So much for this month. See you at the Church or Tuckahoe.
Don....
The Editor’s Quadrant....
The Solar System in February
Mercury- appears as a morning star on February 10th about
10 degrees to the right of where the sun will rise, never getting more
than 5 degrees above the horizon.
Venus comes out of conjunction with the Sun as a morning
star in February but won’t be very visible until late in the month and
even then it will be too low for most viewers to see.
Mars- in the southwestern twilight sky in Pisces, continues
fading in February as its magnitude goes from 1 to 1.3 and the disk size
goes from 6” to 5” across.
Although Jupiter loses magnitude in February, from -2.6
to -2.4, it is still high in the southern sky and next to the moon the
brightest object in the sky.
Saturn, although past its opposition, remains a spectacular
sight in February, shining high and bright in Taurus with rings at full
tilt. Your February Skymap on page 5 shows the 10 p.m. position
of these two planets poised above the constellation Orion.
Both Uranus and Neptune are in conjunction with
the sun in February and will not be observable.
Also forget Pluto in February as it is still lost in the morning
twilight.
Clear Skies!, Frank Sheldon f.a.sheldon@att.net
www.delmarvastargazers.org
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