What you will see on a clear night in
Constellation: The Big Dipper (part of the Great Bear)
Double Stars: Alcor & Mizar
Special Event: Saturn-Moon Conjunction, May 13 and June 9.
Finally, we are enjoying spring weather. On the ground, 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 disappeared over the western horizon.
What happened to Orion with its 3-star belt? Most constellations relocate from east to west as the Earth rotates. Constellations such as Orion, which are well below the North Star, disappear below the horizon during a portion of the day. It will return next winter.
Gone with Orion is SIRIUS, the brightest star in the night sky. Replacing it is ARCTURUS, the second brightest. Here's how you find Arcturus: First, locate The BIG DIPPER high overhead. 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 beyond Arcturus and you will spot another star, Spica. Thus the expression, "Speed on to Spica!" once astronomers have found Arcturus.
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.
The brightest object in the night sky-some astronomers say the most rewarding-is THE MOON. On May 6, 10 and 17, and on June 5, 8 and 15, you'll see the Moon display it's early phases from early crescent, to first quarter and then full Moon.
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.
Saturn is the solo evening planet. As of late April, SATURN was high in the east. During May and June, the ringed planet will drift to the south, then southwest. The best way to find Saturn is to locate Arcturus below the handle of the Big Dipper. Then go to Spica below and to the right of Arcturus. Just above and to the right of Spica is a star-like object, which is actually Saturn. In May and June, Saturn is south of Arcturus. The best way to see the planet's rings is through a telescope.
The SUMMER SOLTICE, or the first day of summer, occurs on June 21. On that day, the amount of daylight will reach its maximum for the year (about 15 hours) and the amount of nighttime will be at its minimum (about 8 hours).
Circle May 13 and June 9 on your calendar. As noted above in Specials Event, a Saturn-Moon conjunction - when the two will appear close to each other - will occur on those two days. Even though the ringed planet will seem to be upper left of the Moon, the two will be far apart. Saturn is ten times as far from the Sun as the Earth: 1.5 billion km compared to 150 million km. The Moon is only 400,00 km away from the Earth. It's no wonder Saturn looks like a star! Use your binoculars for best results.