Different Directions - Moon & Meteorites

Well, to at least keep things into perspective, everything started with the Big Bang. But that is not where we are starting; we start much later with our galaxy.

However, it is cool how far our growing technologies have come, and how far we can now see out into space. Here's one of the Hubble Space Telescope's Deep Field images:

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This view of nearly 10,000 galaxies is the deepest visible-light image of the cosmos. Called the Hubble Ultra Deep Field, this galaxy-studded view represents a "deep" core sample of the universe, cutting across billions of light-years.

The snapshot includes galaxies of various ages, sizes, shapes, and colors. The smallest, reddest galaxies, about 100, may be among the most distant known, existing when the universe was just 800 million years old. The nearest galaxies -- the larger, brighter, well-defined spirals and ellipticals -- thrived about 1 billion years ago, when the cosmos was 13 billion years old.

In vibrant contrast to the rich harvest of classic spiral and elliptical galaxies, there is a zoo of oddball galaxies littering the field. Some look like toothpicks; others like links on a bracelet. A few appear to be interacting. These oddball galaxies chronicle a period when the universe was younger and more chaotic. Order and structure were just beginning to emerge.
The Ultra Deep Field observations, taken by the Advanced Camera for Surveys, represent a narrow, deep view of the cosmos. Peering into the Ultra Deep Field is like looking through an eight-foot-long soda straw.

The Milky Way is the galaxy which is the home of our Solar System -- together with at least 400 billion other stars and their planets, and thousands of clusters and nebulae.

The spiral arms of our Milky Way contain interstellar matter, diffuse nebulae, young stars and open star clusters emerging from this matter of dust and gas.

Our solar system is situated within the outer regions of this galaxy, well within the disk but about 28,000 light years from the Galactic Center. Therefore, the Milky Way shows up as a luminous band, spanning across the sky along this symmetry plane, which is also called the "Galactic Equator." We've see this from Earth, a fuzzy white river of stars. But camera's see more.

While the above image is stunning, all of us at times in our lives, have seen the diffused, white ghosted image of the milky way on a clear night sky, but where we live in its huge arms is sobering.

Our solar system is situated within a smaller spiral arm, called the Local or Orion Arm, which is merely a connection between the inner and outer next more massive arms, the Sagittarius and the Perseus. See below.

As you can also see, our galaxy is loaded with clouds of dust and gas called nebulae. While the gas is primarily hydrogen, it is mixed with nitrogen and oxygen and other lighter gases. The dust is tiny solid grains, a mixture of carbon, silicates, iron -- all coming from the evolution of massive stars and ejected during their lifetimes into the surrounding regions.

The grains form the cores of dust particles, encased in ices of methane, ammonia and water and mixed within the nebulae.

Here's one of the famous Eagle Nebula's columns of molecular clouds. Inside of this column, stars are forming. The red areas are fluorescing hydrogen gas, and the blue areas are solid dust grains reflecting the blue light of embedded stars.

With instruments such as Hubble, astronomers are finding complex molecules in these clouds, some of which are organic. So much so, it is evident that organic molecules are common in interstellar space, that stars born of interstellar dust and gas are also born within a rich organic medium.

A nebula is a stable mass of gas and dust until something compresses or shreds it. Once compressed, regions of turbulence appear which are dense and fragmented. Nebula fragments are like stellar incubators, growing stars from the matter that is absorbed and which continues to be compressed through its own internal gravity.

Our solar system might have formed from a dark fragment and from an exploding older star.

The Star Before Ours

It was many times larger than our star, and existed close, as close can be in space, to the nebula which contained the material that would become our sun.

All stars are a thermonuclear furnace that produces energy to keep it shinning and to keep it from collapsing under the enormous weight of its own overlaying mass.

And like all stars, this massive star had a lifetime, and a life progression. Here's what happened:

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Without supernovae, there would be no carbon, oxygen or other elements that make life possible. Only supernovae release the larger elements from the gravity of stars.

Before the Beginning

The Large Star Masses

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The Star Before Ours

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