PREFACE: I’m going to rely more strongly on sketches I make at the telescope than on photographs, because photos can be a lot cooler than what you can see with eye – the photo can be taken over a long period of time, and reveal colors and structures that we can’t see by eye. This is actually one of the complaints that I have about a number of observing aides; by showing photos with more details than the eye can see, a visual observer could be greatly discouraged instead of being able to learn to see what is there. Happily, planets do not have that problem. Planets are so comparatively bright that sensitivity is not a problem, and in fact the eye does a better job than most non-spacecraft cameras for seeing details on the planets. Plus, there are some really cool planetary images in the public domain.
The primary purpose of my blog over the first year will be discuss each constellation visible from the continental United States in turn, with special emphasis to the Messier Catalog, Charles Messier’s list of 110 galaxies, clusters, nebulae, and … stuff. (I’ll explain that in my first constellation post on Ursa Major – the Big Dipper and more). I’m not just going to be doing that, because I want this to be interesting for anyone who might just be starting a relationship in the night sky.
Some of the easiest objects to find and watch in the sky are the planets, and there is a good reason to have a post about where the planets are right now (and what they are doing), and that brings us to the first planet we will look at, Saturn. Saturn is the sixth planet out from the Sun, and the second largest planet, but the aspect of Saturn that everybody rightfully thinks of is its ring system.
The rings of Saturn are so bright because they are largely made of ice particles, and the diameter
of the ring system is over one hundred and twenty thousand miles across – but the rings are only a few miles thick. We can see the rings of Saturn because Saturn’s orbit is tilted slightly compared to the Earth’s, but even with a tilt, there are still two times during Saturn’s orbit around the Sun at which Saturn is in the same plane as the Earth and we look at Saturn’s rings edge on. At these times, the rings seem to vanish altogether! The next time this happens will be in late September, but Saturn will be too close to the Sun to see, so go ahead and look now, if you have even a small telescope, to see Saturn’s rings as a narrow line.(The disappearing rings were noted by the first person to look at Saturn through a telescope, Galileo, who only saw indistinct shapes on Saturn’s sides. In Greek mythology, the titan Cronos – associated with the Roman ‘Saturn’, although that isn’t really … but I digress – who swallowed his children as they were born to thwart a prediction that his child would supplant him. When Galileo saw “Saturn swallowing his children”, he was so frustrated that he stopped observing Saturn at all.)
Saturn can be found in the west as night falls, south the constellation of Leo. If you are looking above the western horizon, the map below shows you approximately what you would see, without the names and big blue lines. If you have any city lights in the vicinity, then you might just see the stars whose names I have included.
If you want to be sure if you are recognizing the stars correctly, I have included a map from my first constellation blog showing some of the stars that can be found from the Big Dipper. If you can find the Big Dipper high in the sky, then you can follow the two stars of the bowl that connects to the handle along a line that comes very close to the star Regulus.
That’s all we have in the evening, but if you are actually getting up early some morning to look for the space station, or if you just have a time when you can’t sleep, the planet Jupiter (the fifth planet, and the largest planet in the solar system) will be high in the southern sky, and Jupiter will be by far the brightest thing in the area. If you were to look at Jupiter in even a small telescope, the four largest moons of Jupiter (on the same size scale as our own Moon) will appear as a line of stars. The planet Neptune (the eighth planet, about four times the radius of the Earth) is actually very close to Jupiter in the sky right now. If you are able to find Jupiter in a telescope, and you can tear yourself away from the view of the moons, and the bright bands and dark zones of Jupiter’s cloudtops, then you can try and find the planet Neptune to the north and east of Jupiter. Neptune is fainter even than the moons of Jupiter, and shows you as little. While telescopes will show the disk of the planet Neptune, and you can see the strong blue color caused by the methane clouds of Neptune’s atmosphere, that’s all that you get. No matter how strongly you magnify that image, neither Neptune nor Uranus (a little harder to find) will show any features whatsoever. Mark off that you have seen Neptune (hurrah!) and go back to Jupiter.Uranus is much harder to find, located in the constellation of Pisces, which has no bright stars to speak of. I’ll go into more depth in finding Uranus when it becomes more of a evening star.
Venus and Mars are both morning stars right now, visible in the east before sunrise. Venus will be high enough in the sky to find easily. From Venus, Mars is close to the north, and both should be visible in the same field in binoculars. Mercury, the last planet to rise tonight, will rise shortly before the Sun, and would be very, very difficult to find.
(I’m waiting to get into the whole Pluto thing til its own entry. Pluto is up tonight, but forget about seeing it. My own telescope is too small to see Pluto, and even if I could, it would only appear as a dot. Really, this blog is about Saturn.)
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