If you are in the process of planning some vacation this month, make sure you set aside a few days for summer night observing. With the Milky Way in all its glory overhead as seen from the countryside, far from city light domes, you will want to stay up till the first sign of astronomical twilight begins. The observing window for this month in which the Moon will not interfere will be from August 8th to 16th with new Moon occurs on the 12th.

As luck would have it, the night of August 12/13 also happens to be the peak of the annual [imo.net/calendar/2007] Perseid meteor shower with the entire shower occurring from July 17th to August 24th. If skies are clear on peak night, you should be able to see a predicted 100 meteors per hour from 5:00 hrs to 7:30 hrs Universal Time (1:00 to 3:30 eastern). With the combination of vacation time, an absent Moon and a warm August night, this display should be witnessed by a lot of people. Gather the entire family and head out for dark skies.

The comet’s dust deposit that lingers in space is a souvenir of the periodic Comet 109P/Swift-Tuttle. With a 130 year orbit, it last swung by the Sun in 1992 thus littering our part of the solar system with a fresh layer of dusty debris cast off from the comet and is now reseeding back to the icy depths of space. Not all comets produce an Earthly meteor shower. Only those that intersect our planet’s path will cause a display of comet dust striking our atmosphere at 59 km/sec about 100 km above us. Chick Little nor we, will not have to worry about anything falling on us.

So here we have our eight-night observing window with a wide range of stellar objects to view. So what is out there to observe? It so happens that this area of celestial real estate has a lot of ‘favourites’ to hunt down and enjoy. Such as the most beautiful double star in the entire sky – Albireo. Located at the head of Cygnus the Swan that glides against the background Milky Way, this wonderful pair of distant suns lies some 380 light-years (ly) away. The two components are also widely separated and will take literally thousands of years to orbit each other.

Moving a little more than eight degrees to the southeast, we come across the planetary nebula M27. AKA the Dumbbell, the first impression you will see is that of a half-eaten apple. The dead star resides in the center and this is a preview as to what the Sun will look like when it runs out of fuel and dies in about five billion years. It is fairly close to us at some 1,200 ly and is about a fifth the wide of the full moon.

Skipping over to Sagitta the Arrow is the globular cluster M71. Although it is classified as a globular cluster, I have the impression of a well-populated open cluster. Any way you put it we know that it is sitting at an estimated 1,300 ly away, and shines at a decent magnitude 8.5.  

Another planetary nebula not to be missed is M57 – the Ring Nebula. Centred between the lower two stars of Lyra’s rectangle this planetary is a 9.5 magnitude. Very large telescopes will allow you to visually see the parent star (14th magnitude) in the middle of the Ring but CCD camera makes it a cinch. The ring is caused as the dying star that has used up its own fuel, first grows to giant size as it is starving. When the star balloons out to hundreds of millions of kilometres and in our case around the orbit of Mars, gravity cannot hold its outer edges and material gracefully float away to usually form a ball of gas.

A great optical test is the Tim Horton’s star (the double-double). You will easily see a double star in a finder scope someone and three-quarter degrees to the east of the very bright star Vega in the constellation Lyra the Harp. Looking at this 160 ly system at low power in the telescope, you get the sensation that these stars are not pin-point sources. Bumping up the power you now begin to split each star into separate components hence two double stars. The better the collimation of the telescope’s mirrors, the clearer the tiny separations.

A good challenge for a medium-size scope as well as testing sky transparency is to hunt down the very wide Veil Nebula. This every growing and dissipating shell of star stuff is the last remains a supernova – a star that exploded some 15,000 years ago. What a sight that must have been as the 1,400 ly distant star quickly brightened to magnitude minus eight or the brightness of the crescent moon. All is left are two giant arcs of gas, three degrees apart with the western section passing through the star 52 Cyngi. Using an OIII filter will help trace the subtle detail of its structure.

The globular cluster M56 is a dim cluster but still observable. Lying some 32,000 ly from us, it has an estimated width of 85 ly. Only the inner portion is visible and even the core is not as condensed as other globulars. You can find M 56 half was between Alberio and Gamma Lyrae. Move back up the long neck of Cygnus and along the gorgeous Milky Way till you reach Gamma Cygni at the intersection of the wings and the body. Surrounding this spectral class F8 sun are numerous gaseous regions catalogued as IC 1318 or the Butterfly Nebula. 

Although we have seen a few objects that require a telescope to enjoy, nothing can replace the scanning of the Milky Way with low powered binoculars. Literally, hundreds of distant suns fill the eyepiece at any given time as your brain drinks in photons. I have spent many a night simply with wide-angle 7 X 35 binos, a lawn chair, a red flashlight and a good star chart in the countryside. In fact, you will see most of the objects mentioned in this column but to a much smaller degree.

While on the topic of binoculars, our last object is best viewed with a wide field, this is the North American Nebula together with the Pelican Nebula. With an area of almost four moons wide, a telescope will not grab the entire gas cloud. Catalogued as NGC 7000, the North American has an uncanny resemblance to our continent. Residing about 1,600 ly from us this Nebula has star-forming regions. A total of three open clusters numbered NGC 6989, NGC 6996 and NGC 6997 have grown from this stellar nursery. 

The King of planets – Jupiter owns the southern skies. Shining with majestic grandeur, Jupiter shares the sky with the orangey star Antares, the heart of the Scorpion found directly below. As the weeks march on into autumn, follow Jupiter’s movements with respect to this sun. The planet itself is a collection of dark bands and white zones. The Great Red Spot (more of a dull pink) is seen each time the planet rotates in just less than ten hours. But the showpiece of viewing Jupiter is its four main moons. As the main moons swing around its giant parent, we see slight changes in position. At times these satellites cross the face a Jupiter and cast lovely shadows on the Jovian cloud tops. Consult the 2007 Observer’s Handbook for a list of events.

Yes, it’s that time of year when the Mars email hoaxes begin to surface. A description such as “Mars will be as big as the Moon” is completely false. I believe the false statements sprung up in time for the August 27, 2003, close approach. Such bogus emails also came up in 2005 and again this year. Even the dates are wrong. In 2005 Mars was closest on October 30 and this year the closest approach to Earth will be on Dec 18th and it gets its brightest on Christmas Eve. Just keep in mind the red planet and Earth are closest about every 26 months.

Looking ahead to next month there is a potential for a rare meteor storm from the Alpha Aurigids on September 1st. The shower is a product of Comet Kiess which was last spotted back in 1911, one year after Halley. It will be a long time till Earth sees this mountain of ice as its orbit is estimated to be about 2,500 years.

Comet Kiess seems to deposit dense trails of debris along its path. Earth has had glancing blows in 1935, 1986 and 1994. However this year, it is believed that Earth will pass very close to the centre of a dust tail. It appears those who live on the west coast of North America, Alaska and Hawaii will get to see the possible outburst. Keep watching the skies. In case predictions are off.

Until next month, clear skies everyone.

Gary Boyle