ARTICLES
Observation Studies of Constellations in the Earth and Space (continued)
sky. The stars of Sagittarius are not as bright as those of Scorpius,
but the constellation is still easily found. By the way, the two bright
objects adjacent Scorpius in this picture are the planets Mars
(adjacent Antares, its look alike!) and Saturn. These three bodies
form an almost right angle triangle. The cloudy section between
Scorpius and Sagittarius is part of the Milky Way: we are looking
back at our own galaxy and the centre of our own galaxy can be
seen in that area.
you will find several fuzzy patches against the backdrop of the
Milky Way. These are nebulas and globular clusters that will
reward a closer look via binoculars. Use a star chart to find: M8
(Lagoon Nebula), M20 (Triffid Nebula), M17 (Omega Nebula),
M22 (globular cluster right near Lambda Sagittarii) and M21 (open
cluster near M20). There are many other objects to investigate in
Sagittarius.
Photo 7: Milky Way in Sagittarius
Photo 7 gives a clearer view of the sky around Sagittarius, which
appears on its side, almost upside down, here. You can clearly see
the Milky Way, including the centre of our galaxy cutting across
the image. The semi-circle of stars, almost an egg shape, to the
top and slightly left of centre is another constellation: Corona
Australis, or Southern Crown. This constellation is quite pretty on
a clear night with stars of different colours forming the crown. A
large globular cluster, NGC6541, can be found by following the
longer side arc of stars and continuing on.
October – December
As spring rolls on to summer there are still lots of constellations
but compared to autumn and winter it might look less spectacular.
There are fewer easily identifiable and bright constellations and
the sky looks a little more barren. Indeed, even the Southern Cross
is hard to see, especially on October and November evenings,
being low to the south and east near the horizon. Capricornus,
or Capricorn, another constellation of the zodiac, is rather faint
but the pattern of stars makes this easy to find anyway. Looking
like the horns of the goat it is named for, Capricornus will be
found high overhead a little north of Grus. It is shown in Photo 8.
Photo 6: Scorpio and Sagittarius rising
The first trapezium of Sagittarius is comprised of (clockwise
from top left) Gamma, Eta, Delta and Epsilon Sagittarii. The
lower trapezium is comprised of (clockwise from top left) Phi,
Zeta, Tau and Sigma Sagittarii. The star between and left of the
two trapeziums is Lambda Sagittarii. Drawing a line from Eta to
Gamma Sagittarii and going on for the same distance as those
two stars will point to the centre of our galaxy. At this same point
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SCIENCE EDUCATIONAL NEWS VOL 68 NO 4