you will see on a clear night in
Constellation: The Big Dipper (part of the Great Bear)
Double Stars: Alcor & Mizar
Solar System: Venus, Jupiter, & The
Finally, we are enjoying spring weather. Snow has given
way to green grass, tulips, daffodils as well as budding trees and
bushes. In the sky, changes have taken place as well. ORION the hunter,
the largest and brightest winter constellation, has left us. Orion will
be replaced by the Summer Triangle in July-August.
What happened to Orion with its 3-star belt? Most
constellations relocate from east to west as the Earth rotates around
the Sun. Constellations such as Orion, which is well below the North
Star, disappear in the west late in the day. Orion will return next
Gone with Orion is SIRIUS, the brightest winter star.
Replacing it is ARCTURUS, the brightest spring-and-summer star. Here's
how you find Arcturus: First, locate the BIG DIPPER high overhead to
the north. Then draw an imaginary arc-shaped line beyond the handle of
the Big Dipper and you will see Arcturus.
That's why some astronomers exclaim, "Let's arc to
Arcturus." Continue your imaginary line to the right of Arcturus and
you will spot the star Spica.
The Big Dipper
The seven-star BIG DIPPER--the most well known star
configuration in the night sky--is a circumpolar grouping, which means
that we see it year-round because it is close to the North Star. The
Dipper is part of the constellation URSA MAJOR (Big Bear).
Locate the Dipper's bowl. If you draw an imaginary line
beyond the two end stars of the bowl, you will find the NORTH STAR.
Many people think that the North Star is the brightest in the night
sky. Not true! It's way down on the brightness scale (close to no. 50
on the brightness scale). However, it is in the same spot every night
because it is above the Earth's axis.
The North Star is the lead star of the seven-star LITTLE
DIPPER, which pours into the bowl of The Big Dipper. But you have to be
at a very dark site-like a farm or a cottage away from city lights-to
be able to make out The Little Dipper.
There is something unique about one of the seven stars of
the Big Dipper. Look carefully at the second star from the end of the
Dipper's handle and you'll spot a double star, ALCOR & MIZAR. The
star duo is more definitive with binoculars or a telescope.
VENUS appears as a bright”star” in the west and will continue to do so throughout spring and summer.
you can’t see the western sky because of trees and buildings, have your
parents drive you to Wilmot Line, a road that branches off Erb St. just
past the Waterloo landfill. From there you will have a clear view of
Venus will look like a cold “star,” but, in fact,
it is the hottest planet in the solar system with a surface temperature
hotter than Mercury: 500 deg. C. The second closest planet to the Sun
is broiling hot because the surface is like a greenhouse, covered by
clouds of deadly sulphuric acid, trapping in the Sun’s heat. Venus so
hot that all of the robotic probes that have landed on the planet have
burned up moments after landing!
Venus’s day is longer than its year! During its
225-day trip around the Sun, it hasn't quite rotated around once on its
axis; it requires another 18 days. Venus is referred to as our sister
planet since the two are similar in size.
Because JUPITER first appears very low in the southeast
in early May, it would be best to wait until mid-month when it will be
higher. It may be necessary for your parents to drive you to a
park on an athletic field to get a clear view of the south horizon.
Jupiter will also look like a “star,” but not as bright as Venus
because it is farther from the Sun.
With a diameter 11 times than of
Earth, Jupiter is the giant of the solar system. It takes 12 years to
orbit the Sun--about the same time you’ve been on the Earth! The fifth
planet from the Sun is a huge gas ball of helium and hydrogen—so big
that its volume would contain 1,300 Earths.
Note: The Jupiter video shown here includes its four largest moons,
called Galilean moons. Look closely and you will see the moons move
around the planet! Even though they look tiny “stars” through a good
quality telescope, most of them are larger than our Moon.
Are you aware there are about 150 moons in the solar
of the powerful magnetic fields of the four gaseous planets (Jupiter,
Saturn, Uranus and Neptune), they have most of the moons. Since
Jupiter has 65 moons, some observers refer to the giant planet as a
mini solar system.
If you aim a telescope at Jupiter, you will spot the
planet’s four largest moons. Jupiter’s remaining 61 moons are too small
to be seen. Even though the four largest moons appear as tiny dots,
they are about the same size as our Moon. They are always in a straight
line because they are rotating around Jupiter.
The brightest object in the night sky--some astronomers
say the most rewarding--is the MOON. Between May 29 to June 9 and after June 26, the Moon will display its early evening phases:
- May 29 & June 28: full Moon
- May 18 & June 17: crescent Moon.
- May 21 & June 20: first quarter Moon.
The photo below shows the Moon between crescent and first
Craters and "seas" (the grey areas of the Moon) can be
easily picked out with binoculars or a low power telescope. The secret
to viewing the night sky with binoculars is to keep them as steady as
possible: either mount them on a tripod or sit back in a lawn chair
that has a tilted back.
Where to look for the Moon after sunset? The crescent
phase will appear in the west, the quarter phase in the south and the
full Moon in the east.
Did you know that the Moon's craters are the result of
our closest celestial object being pummelled and battered by giant
space rocks or asteroids? If the Moon had an atmosphere, the craters
would have long eroded away from wind and water erosion like what
happened here on Earth. But because there is no atmosphere on the Moon,
the craters have not changed ever since they were formed.
The Moon's craters and mountains are most dramatic if you
look near the terminator, the line that separates the dark side from
the sunlit side. That's because the shadows created by the Sun are the
longest. If you look through a telescope, you can even spot crater
walls disappearing into the shadows.