Types of Stars Series #1 Red Giant

Stars come in a myriad of sizes, colors, and even shapes! Ok, by myriad, I really mean more like 7 major categories, but either way, we are going to begin a series of posts to discover more about them all.To begin, we are going to cover the Red Giant.

Despite the name, the red giant is actually a medium sized star. Red giants are known by their distinctly bright red color, and not fully spherical shape. Stars are formed and sustained by their gravity, and the burning of gases (which we shall cover later). The red giant begins in a much smaller size than it becomes. After it burns through its initial stock of hydrogen, it compacts, then reaches a layer of hydrogen within the star's core. The hydrogen then ignites, expanding the size of the star greatly. This also give the star its color and shape. Once this hydrogen is burnt up (this takes millions of years) the star shrinks into a White Dwarf star.

The most well known example of a Red Giant star is the star Mira. Note the distinct shape.

Cassiopeia

Can you spot the constellation in the image above? The name of the article is your hint. If you cannot, then look for the 5 bright stars that resemble a sideways W shape. That is the constellation Cassiopeia.

Cassiopeia is a Northern hemisphere constellation that is most easily seen during early November. Take note, this is coming up soon! The best way to find it is look in the opposite side of the sky from the Big Dipper. That is where she rests her head at night.

Cassiopeia is, in mythology, the Queen of Ethiopia and mother of Andromeda. Cassiopeia was beautiful, and very vain. She was punished by Poseidon and after her death, was sentenced to hang in the sky for half of the year. That is where the constellation comes in. It is her hanging in the sky for half of a year. To help better picture this, check out the image below.

This constellation makes me a little sad; however, becoming as beautiful as the stars is something to cherish.

Lunar Halo

This is one of the more peculiar sights one can see during stargazing. The first time I saw this, I swore I was imagining it, but when others saw it as well, I felt relieved. What am I speaking of? Well, a lunar halo of course!

In weather lore, these heavenly rings were taken as a sign of impending bad weather. Now, this is supported by scientific evidence. The lunar halo is formed by refraction of light off of ice in the atmosphere. This ice is the very thin, wispy cirrus clouds. These clouds are so high in the atmosphere they almost exclusively exist as ice. Cirrus clouds often precede rainy or snowy weather.

The light from the moon refracts off of the very thin ice of the cirrus cloud, it is bent to precisely 22 degrees. This bend is what makes the circle in the sky. This halo is formed in almost an identical fashion as a rainbow is. Lunar halos are more common in the winter months as the cold temperatures result in more icy clouds.

The next time you see one and think about how this night time rainbow is formed, also think about an umbrella in the next few days.

What's Up With Saturn's Rings?

Saturn's rings are a mystery to most of the human population. We all know they exist, despite them not being visible to the naked eye, but what makes them? Attached above is a picture showing the divides in in the rings orbiting Saturn.

We may know that the rings are made of frozen particles of dust that surround the planet, but that just makes the fact that they form rings more curious. Dust and ice, while on earth, do not form rings, so why would they in space? Well, science has the answer.

The rings are divided up into the A ring, B ring, and so on, all the way out until the farthest away ring, the Phoebe ring. In the space that makes the A or B rings into rings, we find Saturn's moons. The orbit of the moons creates the rings we see on Saturn! Look again at the picture above and see the gaps between the rings. Think about how a moon creates that gap. Those rings must be massive! How great is the art of the universe. God is good.

There is still much to be learned about Saturn's rings, like how the outermost ring is formed (no moon is yet found for that ring). Either way, they are one of the most interesting and beautiful sights to be seen in our solar system.

This is my video book review for my Social Media class. If you all think I should do more videos, please let me know. This is a class project so not too related to my blog topic, but this is still an interesting book. It can help to give you some ideas for your own blog!

Why Do Stars Twinkle?

"Twinkle, twinkle, little star." We all know how the song goes, but do we really know what the song is talking about? Do the stars really twinkle?

Scintillation is the technical term for the phenomenon we know as "twinkling". True twinkling is the oscillation of light from its source that makes it appear to be shaking or shifting. Stars are burning orbs of gas that send light from light years away through space to our humble planet. Once it makes it to our planet, it must pass through the atmosphere as well. As it passes through the atmosphere, it goes through layers of air turbulence that distort our image of the light from the stars. This is what results in what we know as the twinkle of the stars.

This explains how on certain nights the stars seem still, while on others they twinkle. Depending on the air currents of the particular night, you may have either effect. Either way, you are seeing the same light, but one with more distortion than the other. Refraction also plays into this as well, which is why the tiny stars always seem to twinkle. The longer the distance from earth, the less light will get here. The less light, the easier to distort.

This brings us to another interesting point, planets almost never twinkle. This is because they are so much closer to the earth than stars are, therefore; it take immense amounts of turbulence to distort their light.

I am almost sad to publish this post. I hate ruining children's songs for people. Oh well, it's for science, I suppose.

October Moon Phases Chart and Cold Air Effects

http://www.moonconnection.com/moon_phases_calendar.phtml
Above is the calendar of the moon phases for the month of October.

Something interesting to note is how the colder air effects the stargazing experience. Light pollution and air pollution both effect our ability to see the stars above. The effects of this are more prominent during the winter as cold air is more dense than hot air. Because of this, light sources appear more bright in cold than in warm air.

This plays out in two ways. The the first sense, light pollution is a bigger concern as the air gets cooler. On the other side, the cool air means the starlight will appear brighter to us here on earth. If you have wondered if the stars are brighter in the winter, you are right. Well, they are least appear to be brighter.

Get ready to bust out some sweatshirts because some of the best stargazing times are now upon us!

Micah