Below is a copy of investigation #9, “See Through” from 201 Awesome, Magical, Bizarre & Incredible Experiments. A correction is needed for this activity because at this time, Saturn cannot be seen through its rings. But, the Cassinni space craft continues to reveal more about Saturn’s rings. The image shown has Earth labeled. In the image, it cappears that Earth is part of one of Saturn’s outer rings, this like many views into our vast solar system, is an illusion created by the vast distance between Cassini and Earth. This image was taken with Cassini behind Saturn, opposite the Sun and at a distance of about 1.3 million miles (about 2.2.million kilometers) from Saturn. The Sun was an additional distance of about 886 million miles (1.4 billion km). On the date the image was taken, Earth’s orbit brought our home planet to a position slightly behind and to the left of the Sun from Cassini’s perspective.
Yes, Earth is being viewed through the outer ring of Saturn. So, things can be viewed through Saturn’s rings.
Planets unlike stars do not emit light. Thus they are not luminous. Instead, they reflect sunlight and are much closer than are stars to Earth as well as to other planets in our solar system.
Distant stars are not seen through Saturn’s rings because the sunlight reflecting off of Saturn’s rings is so bright. It is the same reason that from Earth you do not see stars during the daytime even though they are in the sky. The light from the Sun is so bright that light from stars is not bright enough to stand out in the daytime sky. Instead, starlight blends in with sunlight, thus stars are not visible on a sunny day. In fact, starlight is more difficult to see on nights with a full moon.
According to NASA scientists, while starlight is not visible in some of the images of Saturn’s rings, the rings themselves act much like a seismograph (an instrument that measures and records vibrations due to earthquakes). Internal movements within Saturn cause movement in the particles making up Saturn’s rings, thus altering their orbit around Saturn. These changes create gaps and waves in rings close to the planet. The following comments from NASA gives information about the importance of these particle vibrations.
In Saturn’s Rings, a Portal to the Planet’s Interior
“It’s like the rings are giving you a window into the interior of the planet, much like earthquakes and the frequencies of the waves they generate give you a window into the structure of the Earth,” says Porco, who’s now the imaging team leader for NASA’s Cassini mission. “We’re using the position and character of the gaps and waves to figure out something about the interior structure.”
But it would be almost two decades before Cassini arrived at the ringed world and could capture the waves with sufficient precision for scientists to accurately read them (“It is fun to see it actually working out,” says Stevenson, who saw Fuller’s presentation at AGU). Now, when a distant background star seems to pass behind the rings as Cassini looks through them, the flickering of the star’s light can reveal telltale patterns of alternating dense and sparse regions — the planet’s seismic signature written in waves and gaps. gaps.
The more we learn about the Saturn rings the more mysterious they are. For example, we have learned that opaque objects have a greater concentration of particles vs the concentration of particles in something that is transparent. Thus, one would assume that the more opaque rings of Saturn are more dense than those that are more less opaque or even transparent. But this doesn’t apply to composition of Saturn’s rings. NASA scientists, via information from the Cassini space craft, were surprised to discover no correlation between the density of Saturn’s rings and their opacity and reflectiveness. The opacity of the B ring varies by a large amount across its width, but new information shows the the mass – or amount of material – doesn’t vary very much from one place to another. Another mystery is that the Saturn’s B ring appears to be 10 about times more opaque than its neighboring A ring. One would think the B rings would have 10 times as much materials. But not so.
What is causing the B ring to be less reflective, thus making it appear so dark? So far, it seems that all of Saturn’s rings are made of the same kind of material, ice with some rock materials. As Cassini gets closer to Saturn’s rings, many questions will be answered and no doubt many more will arise. This is a good year to keep up with the Cassini mission. The craft’s path will take it through the gap between Saturn and its first ring and into Saturn’s atmosphere where it will burn up. Cassini’s Final Epic Year.
Now to tackle a correction for investigation #9 See Through.
First, I want to correct the error.
1. Saturn’s rings are made up of separate ice and rock particles.
2. But, while the particles in each ring do move at high speeds, this motion, like the motion of the dark areas on the spinning paper, is not why the rings appear solid.
3. Saturn’s rings are not solid, instead, the rings appear to be solid because particles making up the rings reflect so much light, that individual particles are not visible.
4. Saturn’s rings appear solid because the resolution of the human eye is very limited. Resolution is all about distinguishing fine details. Even the methods used on the Cassini Saturn mission do not have the resolution to distinguish the separate particles of Saturn’s rings.
5. As the distance increases, the resolution of the human eye decreases. The same is true of optical instruments.
6. Even if the particles in Saturn’s rings were not moving, they are too far away for the human eye or at present, optical instruments on Earth. Even Cassini has not gotten close enough to identify separate particles in the rings. But, this is the year that Cassini approaches Saturn and plans to fly through the gap between Saturn’s atmosphere and Saturn’s first inner ring.
Resolution Activities
1. Make a cluster of dots on a sheet of paper. Test how close the paper has to be in order for you to distinguish separate dots.
2. On a clear, moonless night, find the Big Dipper in the northern sky. Look for Mizar, the middle star in the dipper’s handle. Can you see Mizar’s companion star, Alcor. This is said to be an eye test for Roman soldiers. They had to see Alcor to pass the test and become a sholdier.
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I need to turn in a correction to my publisher. Since it is very expensive to make corrections in published books, I always make a point to “fix” the problem with the very least amount of changes in the text. In fact, I count spaces so that my changes will fit into the space of removed text. Also, I need to keep the diagram of the spinning paper if at all possible. Thus, the changes will be in the Purpose and the Why? section. I am very open to any suggestions you might have.
When I get this problem solved, I will post the correction. For now, I wanted to announce the error and provide information about the most current information about Saturn’s rings. More to come. Sign up for a newsletter.