November is upon us! The nights are getting colder, and this means more vivid, clear stars in the sky. As always, the moon's light will play a factor. Check out the attached link so see the sky chart for this month.
How have you all been liking this blog so far? Please let me know if you have any comments, or questions for things I could cover in future posts. I'd love to answer questions if anyone had them. If not, I will just keep doing what I'm doing. I hope you all are enjoying it!
P.S. be ready for another series about some of the heavenly bodies of the night!
November Moon Phases Chart
Monday, October 31, 2011
Wednesday, October 26, 2011
Types of Stars Series #5 Supergiants
These stars occupy the class of the biggest stars known to mankind. Supergiants are up to 10 to 70 times the mass of our sun. This class is wide in definition and includes the biggest stars we know of, the Hypergiants
The massive size of the supergiants is their life, and their demise. Due to their size, they burn through hydrogen much more quickly than any other classification of star. This results in them having the shortest lives of any star, reaching only about 30 million years. Compared to the possible 30 trillion year lifespan of the Red Dwarf, this is a significantly younger star.
These stars burn through so much fuel and energy that they become incredibly unstable. Their massive size also leads to a relatively lower surface temperature per square mile than most stars. When so much star and instability begins to die, the massive amount of energy of the supergiant is catastrophic. The supernovae are so intense, the star is completely obliterated, and nothing remains of it.
Below is a picture of a supergiant star as it illuminates a cloud of dust that surrounds it.
The massive size of the supergiants is their life, and their demise. Due to their size, they burn through hydrogen much more quickly than any other classification of star. This results in them having the shortest lives of any star, reaching only about 30 million years. Compared to the possible 30 trillion year lifespan of the Red Dwarf, this is a significantly younger star.
These stars burn through so much fuel and energy that they become incredibly unstable. Their massive size also leads to a relatively lower surface temperature per square mile than most stars. When so much star and instability begins to die, the massive amount of energy of the supergiant is catastrophic. The supernovae are so intense, the star is completely obliterated, and nothing remains of it.
Below is a picture of a supergiant star as it illuminates a cloud of dust that surrounds it.
Tuesday, October 25, 2011
Types of Stars Series #4 Neutron Stars
When a star runs out of fuel to burn, it implodes upon itself. This massive implosion of a star is a massive release of energy and gravity is known as a supernova. When a massive star supernovas, it creates a black hole. When a star that is only about 2 times the size of our sun supernovas, it leaves behind a core, and this remaining core is the Neutron Star.
The immense amount of gravity present when a supernova occurs creates this star core that we know as a Neutron Star. The star, as the name implies, is an incredibly dense core of almost entirely neutrons. Because of this, the core is essentially a giant nucleus like that of an atom. It is not held together by fusion like other stars, but solely by gravity. The Neutron Star is essentially a star basely solely on the ease of defining it as such.
Pictured below is the first sighting of a known neutron star. Note the distinct coloration difference from the rest of the stars in the sky.
The immense amount of gravity present when a supernova occurs creates this star core that we know as a Neutron Star. The star, as the name implies, is an incredibly dense core of almost entirely neutrons. Because of this, the core is essentially a giant nucleus like that of an atom. It is not held together by fusion like other stars, but solely by gravity. The Neutron Star is essentially a star basely solely on the ease of defining it as such.
Pictured below is the first sighting of a known neutron star. Note the distinct coloration difference from the rest of the stars in the sky.
Monday, October 24, 2011
Types of Stars Series #3 Red Dwarf
For our third star in this series, we are going to talk about the most common star in the Universe as a whole. I am talking about the Red Dwarf star.
Red Dwarfs are about half the mass of the sun, and burn at about half of the temperature. They burn very slowly, but very consistently. They are among the most steady burning stars we know of. Because they burn so lightly and slowly, they have an incredibly long life span. It is so long, in fact, it is the only star that we do not know what happens to over time. Every known Red Dwarf has been nothing but a Red Dwarf.
It is somewhat surprising that we can even see the light of the Red Dwarf. They, on average, burn at 10% of the luminosity of our sun. Almost all of the light from a Red Dwarf is released as infrared light. Due to the difficulty of capturing an image of a red dwarf, I could only find an artist's depiction of a Red Dwarf star.
Red Dwarfs are about half the mass of the sun, and burn at about half of the temperature. They burn very slowly, but very consistently. They are among the most steady burning stars we know of. Because they burn so lightly and slowly, they have an incredibly long life span. It is so long, in fact, it is the only star that we do not know what happens to over time. Every known Red Dwarf has been nothing but a Red Dwarf.
It is somewhat surprising that we can even see the light of the Red Dwarf. They, on average, burn at 10% of the luminosity of our sun. Almost all of the light from a Red Dwarf is released as infrared light. Due to the difficulty of capturing an image of a red dwarf, I could only find an artist's depiction of a Red Dwarf star.
Sunday, October 23, 2011
Types of Stars Series #2 White Dwarf
The White Dwarf is the next classification of stars we will look at. It is one of smallest forms a star can have, and is thought to be the last phase of many star's lives.
The White Dwarf is a remaining core of a star that has burnt off most of its fuel and did not have the heat to reignite the core. The star is largely composed of electron-degenerate matter, which are electrons that cannot lose anymore energy. This leaves the White Dwarf to stay where it is, slowly cooling indefinitely until it becomes a Black Dwarf.
White Dwarfs are fairly common sights in the night sky. They look very similar to the most common star in our solar system, the Neutron Star. White Dwarfs have about the same density of the Sun and the same mass as the Earth.
Attached below is a picture of a White Dwarf. Note how this one has a much more spherical shape than that of the Red Giant. The stars featured below are Sirius A and B as seen from the Hubble Space Telescope.
The White Dwarf is a remaining core of a star that has burnt off most of its fuel and did not have the heat to reignite the core. The star is largely composed of electron-degenerate matter, which are electrons that cannot lose anymore energy. This leaves the White Dwarf to stay where it is, slowly cooling indefinitely until it becomes a Black Dwarf.
White Dwarfs are fairly common sights in the night sky. They look very similar to the most common star in our solar system, the Neutron Star. White Dwarfs have about the same density of the Sun and the same mass as the Earth.
Attached below is a picture of a White Dwarf. Note how this one has a much more spherical shape than that of the Red Giant. The stars featured below are Sirius A and B as seen from the Hubble Space Telescope.
Saturday, October 22, 2011
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.
The most well known example of a Red Giant star is the star Mira. Note the distinct shape.
Wednesday, October 19, 2011
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.
Tuesday, October 18, 2011
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.
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.
Monday, October 17, 2011
What's Up With Saturn's Rings?
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.
Wednesday, October 5, 2011
Tuesday, October 4, 2011
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.
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.
Sunday, October 2, 2011
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
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
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