Bon Courage

The stars are a source of courage to me, have been for a long time. My dad would point out the constellations to us and Mars. On Fall evenings they were there to greet me after soccer practice. I would get out of the car to open the gate into our driveway, my legs sore from sitting. And as I stood in the cool autumn air, there was Orion in the sky behind our house. This was in Arkansas. My family moved to Niger when I was in 11th grade. The first time the electricity went off I ran outside. There was the Milky Way and all the stars. The next year I had even more reason to love the stars. I took a course where we read and wrote about The Lord of the Rings. Tolkien has an evident appreciation for the stars. Sam says to Frodo, “They do cheer the heart, don’t they?” And they do. They testify to the truth of goodness and beauty. We also sang a song that year which included the line, “We will stand as children of the promise.” God made a promise to Abraham that his decedents will be as numerous as the stars in the sky. And here I stand, here my brothers and sisters stand, a witness to the fulfillment of that promise. God has been faithful over the course of thousands of years. The promise is also a witness of God’s desire for all nations to come to know him. The Gospel, Jesus’s death and resurrection, brought a way for all to come to know God. He is the fulfillment to all nations of the Earth being blessed through Abraham and the reason Abraham’s decedents are as numerous as the stars in the sky.

So the stars give me courage. For their own sake and as messengers. I do not think I will be posting more blog posts here (who knows, maybe I will), but learning more about the solar system and the Universe and sharing it with y’all has been a pleasure. Bon courage wherever life may take you.

Stars in the Night Sky

Voyager: Message in a Bottle

Voyager I and Voyager II were launched from Earth towards the outskirts of the Solar System in 1977. Each was sent for exploration. They have taken many beautiful pictures of planets we had never seen up close. Also, on each satellite was a golden record. This record contained a representation of all of mankind, all of Earth. It contained greeting in different languages, natural and industrial sounds of Earth, songs, and encoded pictures of people and places. The records were sent in hope that someday someone might find them. They are a message in a bottle, sent out to whoever might find them in the vast expanse of the universe. Currently, the Voyager craft are in the heliosheath, the last layer of the blowing of sun’s gas. When they were sent out this distance would have been considered out of the Solar System. This is the farthest away any manmade object has ever traveled.

We can listen to the contents of the golden record from Earth. It causes one to reflect on what it means to be here on Earth. Radiolab presents a wonderstriking podcast about Space and the Voyager vessels. It is like looking far away into the stars in the night sky and seeing ourselves truly for the first time.

 

Astronomy Jargon

Some words I like. Here are some words I’ve encountered in astronomy I had not known elsewhere.

Barycenter–The point of the center of mass between two or more bodies.

Lagrangian points–Zones around the sun where an object placed there will orbit the sun relative the the Earth’s orbital progression.

“Dwarf Planet”–The International Astronomical Union always puts quotation marks around the word “dwarf planet” and “planet.”

Orbital resonances–These are corresponding pulls of gravity in orbiting systems. It causes the gaps in the rings of Saturn and the elliptical orbit of Io around Jupiter.

Troposphere–The lowest layer of the atmosphere where greenhouse warming occurs.

Transit signature–The observable light change made by a exoplanet passing in front of its star.

Chartreuse–A color between yellow and green.

Spirographs–The path caused by a point in a circle rotating around another circle.

Epicycles–A circle moving around another circle.

Spirographic art.

Aurora

The Earth has a magnetosphere that protects us from charged solar particles coming from the sun. However, some charged particles manage to penetrate the magnetosphere. These then follow the magnetic lines of our magnetosphere. If these gain enough energy they can travel down into Earth’s atmosphere. Here they hit atoms and molecules, causing them to radiate light. These collisions produce the aurora seen near the poles. Aurora occur at the poles because solar wind particles are more likely to penetrate near the poles and because the particles follow the magnetic pole lines.

Image by
BaboMike on Flickr.

Image from p_c_w on Flickr.

Image by B Eilertson on Flickr.

Image by jennafa on Flickr.

Why is there water on the Earth?

Photo from NASA.

By the current model of solar system formation, the solar system formed according to what materials condense at which distances. Near the center of the solar system nothing could condense because it was so hot. It was also very dense there, and this was where the sun formed. Farther out from the center, rocky and metallic materials could condense. So terrestrial planets like Mars, Mercury, Venus, and the Earth formed. Then at farther distances hydrogen compounds could condense and there the gas and ice giants formed. But it is obvious from this model that water, which is a hydrogen compound, should not have been able to condense on the earth at its formation. How then are water and other hydrogen compounds on earth?

The answer is comets. These  formed far from the center of solar system, where it was cool enough for water and other compounds to condense. They then later crashed into earth. The compounds were incorporated into earth’s interior by the impact. Volcanoes and other volcanic activity then released these compounds into Earth’s atmosphere and then onto its surface. Earth’s atmosphere and magnetosphere as well as climate then prevented the water from being lost to space or freezing onto the surface.

X-ray Telescopes

An x-ray image of the sun reveals more about the corona.

Light comes at many different wavelengths and energies. The light we see represents light with wavelength from about 400 to 700 nanometers. Infrared light and radiowaves have longer wavelengths (and thus carry less energy) than visible light, while UV rays and x-rays and gamma rays have shorter wavelengths (and carry higher energy). Even though we can only see the visible spectrum, we can build instruments that detect the other sorts of light. Radios pick up radio waves and x-ray imaging at the doctor’s office detects where x-ray light has been allowed to pass through the body.

In astronomy looking at the different wavelengths of light can tell us more about the Universe. For this reasons different sorts of telescopes have been designed. Visible light telescopes are considered normal telescopes, but there are also radiowave telescopes, infrared telescopes, ultraviolet telescopes, x-ray telescopes, and gamma ray telescopes. To observe the different lights the telescopes have to be built in a certain way and sometimes put in a certain location. Since gamma rays, x rays, and infrared light do not penetrate our atmosphere to the surface, telescopes observing these types of light must be launched into high in the sky or into outerspace.

X-ray light is hard to catch. Normal mirrors do not reflect x-ray light, rather the high-energy light simply penetrates the mirror. However, if the mirror is placed at an angle to the light the light will reflect. Many people compare this to shooting a bullet. If you shoot a bullet directly at a metal sheet, the bullet is just going to dent the sheet. But if you just let the bullet graze the sheet, the bullet will reflect off the sheet. So called grazing incidence mirrors focus the x-ray light so that an image can be constructed. This is part of what makes x-ray telescopes different from other telescopes. Many telescopes varying in mission and construction have been sent into space built on this concept.

The incline of the mirror allows the x-rays to be reflected and focused.

XRTs (x-ray telescopes) have allowed us to observe phenomena we otherwise would not have known about or understood as well. The first x-ray telescopes were used to observe the sun. We have also been able to observe the heat distribution between galaxies, detect neutron stars and black holes, and examine supernova remnant expansion.

Thinking about History: Tycho Brahe

Life: Tycho Brahe was born 19 February (10 days from now!) 1473 and died 24 May 1543.

Contributions to Astronomy: He greatly improved  astronomical measurements. As well as making very precise observations himself, he introduced methods and instruments which universally made  measurements more accurate. Also, he observed objects in the sky at various points in their orbits. These measurements later allowed Kepler to verify the idea that planets move in elliptical orbits.

During his Lifetime: In 1584 the first English colony was established in Virginia by Sir Walter Raleigh. Later a scion of this settlement would become known as the Lost Colony.

In 1588 the Spanish Armada was defeated by England. The Spanish Armada was before considered to be invincible.

William Shakespeare lived from about 1564 to 1616.  He greatly contributed to literature by the plays he wrote.

Some Reflection: People in the past and the present build upon the work of people who came before them.  Brahe enabled Kepler to advance astronomy, the Raleigh colony contributed to the formation of the United States, and Shakespeare has greatly contributed to literature. What we know and do now is because of observations and thoughts made by the people before us.

Observing the Sky: Star Parties

“The tires crunched on the gravelly road.

‘How do I know where it is?’ said Mrs. Kelly. ‘It’s so dark.’

‘Look for the red lights,’ said Mi-Su.

. . .

Up ahead–spots of red.

‘Lights out,’ said Mi-Su.

The headlights went out.

Only the red spots were visible now. Some moving, some still.

‘Back at eleven,’ said Mrs. Kelly. ‘Watch Tabby.’ The car pulled away.

Tabby blurted, ‘Where’s the party?’

I pointed to the sky. ‘Up there.’ ”

Smiles to Go by Jerry Spinelli

This book was one of the first books to catch my wonderment for the stars and the night sky. Just going outside and looking up is the first step to observing the sky. But then part of me gets excited about the idea of more formal sky observation–telescopes and refracted light and a group of people together to look at the sky together. Star parties are gatherings where all sorts of astronomers, amateur and not as amateur, bring telescopes and let other people look through them. It is like a food court or a library, only this time offering  a selection of nebulas and planets. Some individuals bring fancy binoculars and others bring their size-of-a-van telescopes. The owners will find points of interest in the sky–the moons of Jupiter, Orion’s Nebula, the Horsehead Nebula (a dream). I haven’t been to a star party yet, but it is part of the future for which I am excited.

You can use the internet (search engines!) to find where the next star party will be in your area. Or check out StarDate.

Source: Real World Racing Photo G on Flickr

The Vast Universe

The Universe is immense. When we look up into the sky at night we can see about 2000 stars. These stars are all native to the Milky Way Galaxy. Our galaxy in and of itself contains 300 billion stars. If we use a telescope we  see more stars in our own galaxy and  beyond the galaxy’s edge. Looking  into the sky is also like looking  into the past. Since  light takes time to travel, what we see now may be minutes or billions of years old depending on how far away it is. The Hubble Telescope once looked into a completely dark portion of the sky, a portion 1/80th the size of the moon. And after a long exposure, this image is what we saw:

Source: Wikipedia

There are 10000 galaxies, GALAXIES, in this image. In the Universe there are an estimated 1000000000000000000000000 stars. Mindblown. Mindblown. Mindblown. (Think of all the grains of sand on earth–that is like the number of stars). Mindblown. Mindblown. Mindblown.

Now about this no-edge of the universe business. Most people who would know believe the universe does not have an edge, though it could be finite in size. What always confuses me about this that it would appear our universe is of some shape, and shapes  have centers. But not the Universe? One way to explain this is to think about the surface of a sphere. If you were to walk along a sphere there would be no center to the sphere as you are walking, just like there is no center to the surface of the earth. You would have to take a step out to see there might be a center within the sphere (the core of the earth). Apparently this is comparable to the Universe. There may be a center, but if so one would only find it in a higher dimension. This still doesn’t make sense to me, but there you have it. Science Blog has an explanation that might make sense to you.

One thought that does make sense to me is thinking about the Universe in terms of the Big Bang. I think about the universe right before the Big Bang. All it is is a pinpoint, a little tiny pinpoint of all matter. Then, amazingly, this pinpoint begins to expand. Time is created! And that is all the universe is, this expanding pinpoint. Everything we see is from this expanding pinpoint. A pinpoint does not have a center, and the universe we have is just this pinpoint expanded. So there is no center; everywhere is the center. If time reversed direction everything would compact not into each other especially, but into this pinpoint. That helps me imagine how the universe not having a center is true.

Welcome

Shoes at the Door by ES

“There, peeping among the cloud-wrack above a dark tor high up in the mountains, Sam saw a white star twinkle for a while. The beauty of it smote his heart, as he looked up out of the forsaken land, and hope returned to him. For like a shaft, clear and cold, the thought pierced him that in the end the Shadow was only a small and passing thing: there was light and high beauty for ever beyond its reach.”

The Return of the King