Bulletin No.10

                                PLANETARY SECTION

Since the last bulletin was issued in April, a great deal has happened in space to
make the work of we astronomers more valuable than ever before .. and the need
for good observations is even more apparent.

As you are aware, the International Union of Amateur Astronomers was founded this
year and the machinery set up for the exchange of information. Observations can
now be correlated and co-ordinated on a world-wide scale. We have had an
exchange already - so keep those reports coming in.

I received a pleasant surprise last week when I received a real pot-pourri of ob-
servations from the Edmonton Centre. Their observers are beginning to function
under the capable leadership of Richard Newman. I understand, too, that revivals
of observing programs are under way in the London and Niagara Falls Centres.

John Calder, an unattached member from Galt, has contributed a large sheaf of very
good observations of Jupiter, made with his 6" reflector. These have been included
in the comments in the Jupiter section of this bulletin.

Tom Tothill of Ottawa Centre has kindly contributed some drawings of Mars and
Jupiter evidently the Observers Group in Ottawa is a live one!

My own Hamilton Centre is very active nowadays as far as observing is concerned.
Several new telescopes have come upon the scene and these are being used to
good advantage.

Mariner 6 and Mariner 7 have passed by Mars and come up with some startling
findings. These make observations more important than ever - so let's use
those telescopes a lot during the rest of the summer and throughout the autumn.

MERCURY:  Very little has been done on this planet. Observers should look for
surface markings and record the phase angle as often as possible. An excellent
elongation of Mercury will occur on the days surrounding October 14.

VENUS:    Venus cannot be observed with much success for the rest of 1969. A
great deal of work was done on this planet by the Planetary Section earlier in the
year. A report of this will appear in the Journal of the British Astronomical Associa-
tion (this was set up through the I.U.A.A.).

MARS:     The optimum time for observing Mars has passed. Much excitement
was generated in June when Barry Sherman of the Hamilton Centre discovered one
of those elusive yellow clouds on Mars, If anyone else saw one during the past
apparition, would you please let me know? (I have contacted many paint dealers
with regard to obtaining some chips for our colour comparison project but have
been totally unsuccessful! Can anyone help out?)

Planetary Bulletin No. 10	                                          -2-

JUPITER:   The giant planet was observed well this year. By comparing observa-
tions, I am working out a correlation between the darkness of the Southern
Equatorial Belt and the position of Callisto. It appears to be a valid correlation
but many observations are needed.

The Planetary Section has furnished three dozen satellite timings of the four
Galilean satellites to the Observatorio de Valonge of the Brazilian National Uni-
versity at Rio tie Janeiro. Again this was set up by the I.U.A.A. This all goes
to prove that our observations really are of value -- if reported.

SATURN:     A report of the work of the Section on Saturn will appear in a forth-
coming issue of the JOURNAL. Saturn is getting into a favourable position for
observing, so I hope that you will start making those Intensity and magnitude
estimates soon.


The response to these bulletins has been most encouraging. Just one or two
Centres have not written some form of acknowledgement, so, PLEASE - if your
Centre is one of these, write a note to tell me what you are doing in the way
of Planetary observing, even if it is nothing!

Don't forget - communication between Centres was the big issue at the recent
General Assembly.

                                                  Kenneth E. Chilton,
                                                 National Co-ordinator,
                                                  Planetary Section,
                                   Standing Committee of Co-ordination of Centre
                                            93 Currie Street, Hamilton 57, Ont.
                                                 Phone: 416-388-0586.

14 August, 1969.
Planetary Section Bulletin No. 10
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