AstroNotes 1981 March Vol: 20 issue 03

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A S T R O N O T E S
ISSN 0048-8682
The Newsletter Magazine of the Ottawa Centre of the RASC
Vol. 20, No. 3
Editor....
Addresses..
Circulation
$5.00 a year
Rolf Meier....
C.R. Molson...
Barry Matthews
March, 1981
4-A Arnold Dr....820-5784
2020 Garfield___ 225-3082
2237 Iris St.... 225-6600
OBSERVER'S GROUP MEETING - FEB 6
Susan Argue
Brian Burke opened the meeting at 8:20 pm. There was
a request from Robin Molson that if the gold from the
Citizen's Gold Rush Contest is found by a member, the
Ottawa Centre would love a donation.
The meeting's opening speaker was Frank Roy, with
slides taken with the Aero-Ektar at IRO. This month's quiz
contained such objects as Orion, Canis Major, Canis Minor,
the Beehive Cluster, the Rosette Nebula, and a couple of
slides of Jupiter and Saturn.
The main speaker of the evening was Ted Bean, our in­
strumentation coordinator. His subject was spiders, which
got their name from their web-like appearance. The entire
spider assembly is a way to mount the secondary mirror in
such a way so that the incoming light is reflected out
through the eyepiece. This apparatus is used in a Newton­
ian telescope.
They come in various spoke patterns,
ranging from 1 to 4 vanes.
Rob Dick was up next showing slides from Tobago. The
few shots that were of the night sky showed Eta Carina and
the Crux.
Up next, with more easy-to-make gadgets was Paul
Mortfield. A few of his samples were a homemade camera, a
finderscope, an eyepiece holder, and a grip for the tele­
scope control.
Dave Fedosiewich was up with reports of Comet
Bradfield, Comet Panther, and an 8th-magnitude nova that we
may be able to observe at the next star night.
Then another astronomer-in-disguise, by the name of
Rolf Meier, showed slides of the flora and fauna around
Tucson, Arizona.
The only slide containing stars showedthe constellation Hydra (perhaps - nobody was sure). Also
shown were some slides of the observatories on Kitt Peak
and Mt. Hopkins.
Brian Burke then spoke of the coming grazes and occul-
tations, two of which take place over Ottawa.
The meeting closed, the latest in months, at 10:40 pm.
*
* *
OPT1CKS
Box 6245, Station J
Ottawa, K2A 1T3, Ontario
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AMATEUR
ASTRONOMER'S
HANDBOOK
by J.B.
Sidgwick
JUST PUBLISHED
New fourth edition now
available!
Completely
revised b y James M
u
i
r
d
e
n
.
"The reference classic on
all matters relating to
astronomical instrumenta-
tion and practice, apart
from actual observing
tech niques... i t 's an in-
dispensable reference
which completely outdates
all earlier editions."
New S cientist, July 3,
1980.
568 pages
Enclosed is my check or
money order for
copies
each $32.00
$1 fo r postage
$1 . 0 0
and handlin
total
A S T R O N O M Y
m a g a zine,
and AMATEUR TE L E S COPE
M A K I NG
enclosed
AMATEUR ASTRONOMER ' S
HANDBOOK,
4th
edition.
Name :_______________________
Address:Dr. Allan Cooke spoke to a full house of over 400
people at the February 6 Centre meeting.
The many new
faces indicated that the meeting notices sent to the local
media succeeded in reaching many members of the public.
Dr. Cooke's presentation was about the Voyager flyby
of Saturn and the material he presented was as spectacular
as that which he presented last year for Jupiter. As with
his last talk, many of the slides he presented had not been
seen by most of those in attendance, nor had sane of his
explanations of the various phenomena been published.
The audience warmly applauded his presntation as the
secrets of Saturn were still ringing in their ears.
* * *
OBSERVER'S MANUAL
Robert Dick
After almost a year in production, the Observer's
Manual of the Ottawa Centre is now in for duplication.
They will be sold at both Observer's Group and Centre
meetings.
The 82-page book is roughly the size of the Observer's
Handbook and will be sold to members of the Ottawa Centre
for $5 and non-members for $8.
Those who are not able to attend meetings may order
their copy by writing to the Centre.
Your cheque must
accompany your order.
*
NOTICE TO KEYHOLDER S
*
*
The Observatory Committee
The lock at IRO will be changed on April 2nd and new
keys will be distributed to keyholders
at the Observer's
Group Meeting on April 3rd. In order to obtain a new key,
your old key must be turned in and the annual fee paid.
The annual fee, as last year, is $20.
The Observatory Committee will review the list of key­
holders every year.Astroscan 2001 - $200
4 1/4-inch mirror, 17-inch focal length, 28-mm RKE eyepiece
giving 25 x, base, dust cover, carrying strap
Wire mesh - $225
originally for radio telescope, approx. 1/16-inch
galvanized wire, 1 x 1 1/2-inch spacing, 5 rolls available,
3 x 100 feet each
*
*
*
OBSERVING THE PLANERS IN FEBRUARY
James Black
The planetary viewing in February was good. I had one
chance to view the planets through the 16-inch at IRO.
Dave Fedosiewich, his friend Steve, and I went to IRO on
February 14 to view the planets and whatever else we could
see.
The sky quickly clouded over, however, and we were
forced to go inside and drink IRO's deadly hot chocolate
and the killer cookies, which were rather stale. Around 10
pm the planets were at a reasonable viewing elevation and
we decided to view
them, even though the sky looked like
tomato soup.
The
viewing turned out to be pretty good
after all. We left around 11:30 pm.
The month of February was half clear, and half hazy.
I hope March will be better for viewing the planets.
It
would be good to see more people interested in planetary
viewing. I would like to know if anyone else is interested
in going out to IRO to observe.
If you are interested,
give me a call at 224-2891 any evening or talk to me after
the meeting.
The Astro Club at Merivale High School, to which I
belong, is to have an outing soon. I would like to borrow
an 8-inch telescope for this project. If anyone can lend
me one for the evening, please give me a call anytime after
3:30 pm. Thanks.
The chart on the next page shows the planetary viewing
for the month of March.
*
*
*PLANET NAME POSITION DATE AND TIME
MERCURY
mag = 1.1 LOW WESTERN SKY
AFTER SUNSET 4.5°
ABOVE HORIZON 1-10 FIRST DAYS OF
FEB.
6:00 EST OR 45 MIN.
AFTER SUNSET
VENU S
mag= -3.4 LOW IN MORNING
SKY CONSTELLATION
CAPRICORN. 11°
AWAY FROM SUN 3-10 DAYS OF FEB.
26 FEB. MERCURY
PASSES 6° NORTH
OF VENUS
MARS
mag= 1.4 CONJUNCTION MOON
MERCURY AND MARS
ON 5 th 5TH OF FEB.
DISAPPEARS INTO
MORNING SUN
JUPITER AND
SATURN
mag= .8 OPPOSITION ON 26TH
MARCH.
JUPITER
23 HOURS LATER
THAN SATURN BOTH PLANETS RISE
ABOUT 9 P.M.
mag JUPITER — 1.9
URANUS
mag. 6 AND
HAS A 3.6"
DISK MORNING OBJECT
LOCATE BETA SCORPII
2.9 MAG DOUBLE STAR
2° WEST OF THESE MORNING OBJECT
ABOUT 2 A.M.
STARS
NEPTUNE
MAG. 7.8 AND
2.4" DISK
RADIO SOURCES
2° N. AND 1-1.5°
E. OF 51 OPHIUCHI
A 4.9 MAG STAR
MORNING SKY
3:30 A.M. L.T.
Frank Roy
Although many thousands of radio sources have been
identified so far, only the very strongest can be picked up
with amateur radio astronomy equipment. The Ottawa Centre
of the RASC has a very large amateur radio telescope at the
Indian River Observatory, which is located 35 miles west of
Ottawa.
The instrument is called the IRO Radio Interferometer
(shortened to IRORI).
The IRORI has picked up all the
stronger radio sources, that is, the sun, Cas A, Cyg A,
Taurus A, and Virgo A. We have yet to pick up the stronger
sources of the southern hemisphere. In this article I will
discuss Taurus A and Virgo A.This is M 1, the Crab Nebula, a supernova remnant.
It
is located near the star
Zeta Tauri, which marks the
southern tip of the Bull's horn. The nebula looks like a
small blob in a small telescope but reveals many fine fila­
ments when seen through the 16-inch at IRO.
It was dis­
covered visually in 1731 by the English amateur John Bevis.
The nebula was first detected as a radio source in
1948 and was soon found to show polarization.
Most of
M 1's energy canes from synchrotron radiation. In 1968 the
Crab Nebula was found to contain a pulsar with a period of
0.033089 seconds, or a frequency of about 30 Hz. The offi­
cial designation is PSR0531 +21.
The reproduction is a fringe from IRORI of Taurus A at
a frequency of 238.5 MHz. The source stays in the beam for
about a half hour.
Virgo A:
RA 12h 28.3m, Dec +12 40'
NGC 4486, M 87
From Burnham's: "This is the giant elliptical galaxy
famous for its protruding jet, and one of the largest mem­
bers of the Virgo cluster.
It has a total photographic
magnitude of 9.7 and an apparent size of 3.0 minutes.
It was originally detected as a radio source by J.G.
Bolton in 1948.
It is listed as 3C 374 in the Cambridge
catalogue of radio sources and ranks 5th in intensity among
all known radio sources of the sky.
The strong radio
energy appears associated with a curious optical feature
first mentioned in astronomical literature by H.D. Curtis
at the Lick Observatory in 1918: 'The brighter central por­
tion is about 0.5 minute in diameter...no spiral structure
is discernible.
A curious straight ray lies in a gap in
the nebulousity...apparently connected with the nucleus by
a thin line of matter.' This peculiar nebulous jet appears
to extend outward from the nucleus on the northwest side;
it is some 20" in length and about 2" wide. Photographs
with the 200-inch reflector reveal that the jet contains 3
main condensations, and is much bluer than the light of the
galaxy itself. According to M.L. Humason (1954) the spec­
trum of the jet is continuous, showing neither absorption
nor emission lines. In 1956, W. Baade discovered that the
light of the jet is strongly polarized. More recently, in
1966, it was discovered that M 87 and its jet are a strong
source of x-ray emission; the intensity of the x-ray energyis at least 10 times that of the combined optical and
emission. The length of the jet is about 4100 ly and the
width about 400.
The combined radio and optical studies suggest that
the jet was formed by an ejection of material from the nu­
cleus and that the source of radiation is the synchrotron
process, in which high-speed electrons are accelerated in a
magnetic field.
The original course may have been some
sort of gigantic outburst in the nucleus such as nowROYAL ASTRONOMICAL
SOCIETY
OF CANADA
XXXXX
CENTRE MEETING
DATE:
Wednesday, March 11, 1981
SPEAKER: Dr. P.A. Feldman
Herzberg Institute of Astrophysics
National Research Council
Ottawa
TOPIC: New (Astronomical) Light on the Enigma
of The Extinction of the Dinosaurs
TIME:
PLACE:
8:15 P.M.
Auditorium
National Research
Council
100 Sussex Drive
Ottawa
- Sixty-five million years ago, giant reptiles were
the dominant life forms on our planet. Their sudden dis­
appearance in a general biotic crisis of global propor­
tions has remained an outstanding mystery, despite many
hypotheses which have been advanced to explain the extinc­
tions. This talk will focus on the various proposals
which are specifically astronomical in character. Some
remarkable new evidence will be reviewed. There are many
who now believe that this evidence points to a realistic
extraterrestrial explanation: The collision of earth
with a large Apollo object (an asteroid in an earth cros­
sing orbit).
PRESIDENT: SECRETARY:
K.F. Tapping
593-6060
684-1186 C.R. Molson
725-3082
996-0845appears to be in progress in other odd galaxies such as
M 82 in Ursa Major and NGC 1275 in Perseus."
The fringes are from IRORI with a chart speed of one
and a half inches per hour.
Notice that the fringes are
noisier that those from Taurus A.
reference:
Burnham's Celestial Handbook, 1978, Volume 3,
p. 1843 to 1861, 2092 to 2096.The best Quadrantid meteor shower in many years was
observed by a group of Canadian amateurs from the heart of
the Arizona desert.
While visiting Kingston member David
Levy at his present home in Corona de Tucson, we took ad­
vantage of the excellent skies to observe the display.
London members Peter Jedicke, Gerald Schieven, and Dianne
Kaptaniuk observed with David in his back yard, while Eric
Clinton and myself drove about 5 km south to a site in the
desert.
Two cameras were operated at each location,
resulting in several overlapping photographs of meteors. A
beautiful 1st-magnitude Quadrantid was captured at both
sites, and these photographs have been submitted for pub­
lication.
My own visual observations began at 02:20 Mountain
Standard Time, and continued until dawn, 05:50 am.
I ob­
served a total of 152 meteors, 112 of which were Quadran-
tids. An interesting note was that an unusually high non­
shower rate of about 10 per hour was seen, suggesting that
perhaps another shower was contributing a significant
number of meteors.
While the raw data was collected during 10-minute
intervals, it has been reduced here to the form of a graph
which shows the variation in hourly rates. The points on
the graph were determined as follows: The total number of
meteors for 3 consecutive 10-minute intervals (30 minutes)
was combined and an hourly rate determined (simply twice
the total in that half-hour period). This hourly rate is
plotted for the middle of the half-hour period. The next
point is determined from the last 2 10-minute intervals
used for the present point, plus the next 10-minute inter­
val.
For those familiar with spectral, or Fourier
analysis, the analogy is that of a bandpass filter with a
"bandwidth" of one-half hour slowly being "swept" over the
raw data.
A wider bandwidth would result in a smoother
curve at a loss of resolution, but a narrower bandwidth
would give a "noisier" curve.
I think the half-hour
bandwidth was a good compromise.
A striking feature of the graph is the decline in
rates between 04:35 and 05:15, and the subsequent in­
crease. The predicted time of maximum for this shower was
06:00 MST, although a peak rate of 52 Quadrantids per hour
was observed at 04:35.The 1981 Quadranti ds
as seen from Arizona
Points are plotted for Quadrant id rates and also for
total meteors, the difference between the two curves being
the non-shower rate.
Data for the observing site is as follows:
Site:
5 km south of Corona de Tucson, Arizona
latitude 32 degrees north
elevation 3000 feet
Observer:
Weather:
Times:
Rolf Meier, facing S
very clear and dark, visual limiting magnitude
about 7.0, temperature +10 degrees Celsius
Mountain Standard Time (GMT minus 7 hours)
Thanks to to Eric Clinton for operating the cameras
when the rates increased. Special thanks go to David Levy
for his hospitality, including the use of his 6-inch clock-driven telescope, his van, and for ensuring such fantastic
viewing conditions.
And now, a report from another Ottawa Centre member
who also observed the Quadrantids from the southwest:
* * *
THE 1981 QUADRANTIDS FROM COLORADO
Chris Martin
While browsing through last month's Astronotes, I was
pleased to see that there were some loyal observers who
braved the January winds and seek out the elusive
Quadrantids.
Normally, this seasoned observer would have
joined the group for such a venture, but I was conveniently
out of town, in Boulder, Colorado.
However, let it be known here and now that no old-time
meteor observer ever forgets. In fact, not even past pres­
idents of the Ottawa Centre!
Who, pray tell, would that
be? Peter MacKinnon.
It was during my visit to Peter and his family in
Boulder that the second of January happened upon us in a
clear and sunny fashion.
Temperatures were just about
right. The high for the day was around 20 degrees Celsius
with a low for the evening about 3 or 4.
Setting the alarm for 4 am (MST), we arose to clear
skies on the morning of the 3rd.
It was the first time
that I had to wear my winter coat during my journey south.
Peter and I walked over to a nearby field and slid into our
sleeping bags.
We had no fear of being buried in snow
since mild temperatures and little precipitation made the
ground high and dry.
Our observing time amounted to one
hour and forty minutes, with a total of 120 meteors between
us.
Here is some of the observing data:
Site:
Lafayette, Colorado
latitude 40 degrees north
elevation 5500 feet
Observers:
Weather:
Time:
Chris Martin, facing SSW
Peter MacKinnon, facing E
Clear skies, temperature about 4 degrees Celsius,
limiting magnitude about 6.0, in pre-dawn
Mountain Standard Time
(GMT minus 7 hours)MacKinnon
Martin
Quadrantids Non
Overlaps
Quadrantids
Non
20 10 (8) 26 19
15 8 (10) 20 2
time
04:40 to
05:40
05:40 to
06:20
35
18
46
18
21
It would probably be deduced that since we saw 46
meteors in the first hour of observation and 45 in the
following 40 minutes, that the hourly rate was increasing.
Both Peter and I remarked that this was the first time
we had observed the Quadrantids under such ideal skies and
in such warm temperatures.
I hope that I might have such an opportunity to do the
same again.
It was a successful night all in all.
My
thanks to Peter MacKinnon for keeping the statistic.
*
SOLAR SYSTEM SCAN
* *
Barry Matthews
As 1981 opens I would like to propose a pair of new
programs for Ottawa Centre or any other centre member.
These programs are designed to look at all members of the
solar system except for the sun.
Program number one will be associated with the moon
and will give the newcomer as well as the old hand a
slightly new view of our nearest neighbour. The first step
is to make up a declination meter:
1) Cut out or copy the declination scale on the last page
of Astronotes and glue this to a piece of stiff plastic or
wood. A large protractor will work just as well.
2)
From a map or from the Observer's Handbook find the
latitude of the city you live in.
Subtract this from 90
degrees and mark it on the south side of the scale.
3) Obtain a piece of wood at least 1 x 1 x 30 inches and
nail a 6 x 8-inch piece of plywood to it.
4)
Place 2 small screw eyes in the 1 x 1 x 30-inch piece
in a straight line at least 25 inches apart.
The smaller
the screw eyes the better.5)
Place the stick between 2 supports and level care­
fully using a weighted string as a plumb line.
6)
Find the balance point of the bar and fasten this to
the verical pole with one bolt.
Using the declination meter
Wait until the moon is about to pass the meridian (the
north-south line) and sight on it through the screw eyes.
Record the declination, together with the date and time.
This record should be kept daily for at least a month.
After taking your daily declination readings attempt
to locate the following features on the moon and record
these on a 6-inch circle:
4-day moon
7-day moon
Endymion
Aristotle
Hercules
Cassini
Sea of Crises Julius Caesar
Lengrenus
Alphonsus
Gutenberg
Catharina
10-day moon
20-day moon
Tycho
Bay of Dew
Marsh of Disease Aristarchus
Sea of Clouds
Riccioli
Sea of Rains
Camaldi
Copernicus
Keplar
When all these recordings have been made, give me a
copy at an Observer's Group meeting.
Program number two is the Planetary Scan.
This is
very simple but will take a little persistence on the part
of the observer. The planetary scan takes about one month,
depending on the observer's enthusiasm.
Here are the
steps:
1)
Plot and identify all the planets in the sky.
The
positions can be plotted by wide-angle photography or by
careful sketches of their postion in relation to the
stellar background.
2) Use any telescope or binoculars for positive identifi­
cation.
3)
Draw a simple sketch or take a photograph of the
planet.
4)
Record your observations showing date, time, instru­
ment used, and your personal impressions.
5) Send me a copy of your observations.
It is my intention to present
achievement for this Solar System Scan.
Good viewing and good luck.
a
certificate
ofastro
TO
notes
CAST
MS. ROSEMARY FREEMAN
NATIONAL SECRETARY
THE ROYAL ASTRON. SOC. OF CAN.
124 MERTON STREET
TORONTO, ONTARIO
M4S 2 Z2