The most famous constellation in the entire sky has to be Ursa Majoris – the Big Bear. Its seven stars also silhouette a kitchen pot and in England, it is regarded as “the plough”. There are four suns representing the pot along with three more for the handle. With all the alias names to its credit, the term the Big Dipper heads the list. In fact, this asterism doubles as a guidepost to finding the North Star called Polaris. The pointer stars Merak and Dubhe located 79 and 124 light-years from us respectively, point to the famed northern marker which is also the end of the little bear’s tail. Also, check out the double star in the bend of the handle. Their names are Alcor (the rider) and Mizar (the horse). Although not a physical double, Mizar is the brighter of the two. Splitting these two with the naked eye is a good indicator of sky transparency.

Aside from its directional aid, this stellar group plays host to a wealth of deep-sky objects. Let us begin our tour of the Big Dipper with M101 – the Pinwheel Galaxy. Small telescopes will only reveal the bright core of this magnitude 7.7 structure. However larger apertures reveal a few patches of nebulosity in the galaxy’s spiral arms. M101 is some 27 million light-years from us and is flanked by three smaller galaxies. Just over a degree north of M101, we come across NGC5473 and NGC5485. Both glow at magnitude 11.4 and are small with bright nuclei. In fact, NGC5485 is nestled in a chain of four stars and has a 13th magnitude sun parked right next to it. Now flip over to the other side of M101 and pick up NGC5474. Another round like galaxy that is a bit brighter at magnitude 10.9, but does have a nucleus strangely oriented off to one side.

Next, locate Phecda, the bottom left bowl star. Keep this star out of the eyepiece field of view while sweeping up a nice elongated galaxy with a bright core catalogued as M109. This distant island of stars is about 55 million light-years away and owns a brightness of magnitude 9.8. Continuing south by some two degrees, a couple more elongated galaxies will greet you. First is NGC3953 shining at magnitude 10.1 and then we have NGC3917. At 12th magnitude, it could be a challenge since there is no bright core as per NGC3917.

From Phecda, move to Merak (one of the pointer stars). Three-quarters of the way and a bit south you will come across the ghostly hollow eyes of the Owl Nebula. Deemed as an irregular planetary nebula it is located about 2,600 ly from us. While moving in line from the Owl to Merak, stop at M108. At 10th magnitude, this very elongated galaxy has a few bright knots.

For a bit of a challenge, might I suggest a close galaxy pair known as NGC3958 and NGC3963? Separated by only eight arc minutes, they are listed at 13th and 12th magnitudes respectively. If you are successful and want the bag another pair, try the combo of NGC4290 and NGC4284 listed at magnitudes 12th and 14th respectfully.

A favourite galaxy pair shown at star parties is hands down, M81 & M82. Both distances are estimated at 12 million light-years away and are very attractive in the same field of view. At magnitude 6.9, M81 is the easier of two to pick up with M82’s value set at magnitude 8.4. M82 appears distorted as a result of the two galaxies' interaction tens of millions of years ago. It is quite evident that M81 won the confrontation.

We end off the galactic tour with an object close to the Bear’s border. M51 – the Whirlpool Galaxy is a magnitude 8.4 face-on galaxy and is another fine example of galactic interaction. This 37 million light-year face-on galaxy portrays majestic spiral arm structure in moderate-sized instruments. Any light pollution will hamper your seeing this detail. The distorted remains of NGC 5195 appear to be hanging off one of the Whirlpool’s arms.

Just after 7:30 pm. (EDST) on May 10th, you can watch the nearly full Moon as it sweeps over the first magnitude star Spica in the constellation Libra. With the Sun still low in the western sky and poised to set about forty-five minutes later, you should witness this event in any size telescope. About an hour later, Spica emerges from the moon’s other side.

The king of planets – Jupiter is in opposition (closest to the earth and rises at sunset) on May 4th. Opposition is the best time to view any planet and Jupiter is no exception. On nights of good seeing, try to resolve the many dark bands on the disk. Jupiter sports many other features such as bluish squiggly festoons, smaller earth size white ovals, the Great Red Spot and of course the four Galilean moons. Please refer to the Observer’s Handbook page 199 for a table of timings of these moons as they transit across the face of Jupiter with a tiny shadow following.

The Lord of the rings, Saturn is swinging back east to once again brush just south of M44 - the Beehive cluster on June 3rd. The crescent Moon, star cluster and Saturn will paint a wonderful portrait on the night of May 31st. This will be your last opportunity to see Saturn and M44 together. We will have to wait till early September 2064 to catch them in the September morning sky.

Periodic Comet Schwassmann-Wachmann 3 (also known as Comet 73P is still disintegrating. The last count is 30 small fragments. However, fragments B and C can be spotted. As of recent, Fragment B has split again. Check the sky on the night of May 7th at about 11:20 p.m. EDT as fragment C sweeps past the Ring Nebula - M57.  The near It will also make a lovely portrait with the backdrop milky way of May 12th, 13th, and 14th for a truly rare event. If you remember back to Comet Shoemaker-Levy 9 in 1994, we saw a once in a millennia event of a chain of 23 comet fragments slamming into Jupiter without seeing the comet train. We can now see the splitting of a dying comet as its life literally falls apart. This comet will not be colliding with anything.

Lastly, the Ottawa Centre will be hosting this year’s General Assembly (GA) on Victoria Day weekend from May 18 - 22. If you have never been so a GA in the past, this would be a great opportunity to meeting members from around the Society, as well as taking in many informative paper sessions and workshops.

Till next month – clear skies

Gary Boyle