Sunday, November 18, 2012

Viewing Jupiter and Saturn!

There is little doubt that when viewing planets in our solar system the two most likely to elicit a gasp of surprise from a first time planetary viewer are Jupiter and Saturn.

In recent weeks Jupiter has been rising at a time early enough to be high in the horizon by 9pm. If you view too early, 6pm or so at the time of this writing the planet is too low and will likely result in poor seeing conditions which means that air turbulence will cause a bit of blurriness and shimmering. If however you view later in the evening there is less turbulence and it is higher in the sky so what turbulence there is will be less. This is especially noticeable at the high magnification used for viewing planetary details. With my 8" diameter scope I use a 5mm eye piece which results in a magnification of 240x (this is figured by dividing the focal length of the scope by the eyepiece, in my case 1200mm/5mm=240x). This lens pushes the limits of my scope and unless seeing conditions are excellent my views are poor.

This past week I've had several occasions to view Jupiter and it has been a fantastic view each time thanks to excellent conditions. At high magnification I can view several distinct cloud bands as well as the Great Red Spot as well as several moons, usually four depending on the time.

Saturn is a bit more tricky at this time due to its position in relation to our planet's daily revolution. At the moment Saturn rises just before the sun in the morning and sets just before the sun sets which means that to view it you have to look to the south east just before sunrise and it will be visible to the naked eye below Venus which is by far the brightest object in the sky at that time. At 5:50am Saturn will look like a small star midway between the horizon and Venus. Through my 8" scope with the a less powerful eyepiece such as an 18mm the rings are visible but the planet appears fairly small. With the 5mm eyepiece and good seeing conditions the rings are easily visible and the overall image is stunning even in the bright morning light. In fact, I was still able to easily view the planet after it was no longer visible with the naked eye. Of course with a bright sky the color and details are not as clear.

Of course this changes with each day because Saturn rises earlier in relation to the Sun and within just a couple weeks will provide a much better view with a much darker sky. At the end of November Saturn will be easily viewable at 5:15am when the sky is significantly darker. Around November 26 and 27th Saturn will be passing behind Venus which should provide an interesting view! By mid December the planet will be well above the horizon by 5:15am and the sun lower which will provide an incredible view.

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