Galaxies

The Milky Way galaxy holds a special significance to humans as it is our cosmic home. However, in the grand scheme of the universe, our galaxy is an ordinary barred spiral, one among billions of galaxies scattered across the cosmos.

When you look up at the night sky, a broad, luminous band stretches across the heavens. Ancient civilizations described this celestial feature as a "river," "milk," or "path." This striking band of light is the central plane of our galaxy as seen from one of its outer arms. The Milky Way spans approximately 100,000 light-years across, contains over 200 billion stars, and has vast reserves of gas and dust capable of forming billions more. To put it in perspective, one light-year equals 5.88 trillion miles (9.46 trillion kilometers).

Our solar system is located about 30,000 light-years from the galactic center and roughly 20 light-years above the plane of the galaxy. Interestingly, more than half of the stars in the Milky Way are older than our sun, which is approximately 4.5 billion years old.

The most common type of star in the galaxy is the red dwarf. These small, cool stars have about a tenth of the sun's mass. Initially, red dwarfs were thought to be unsuitable for hosting life-bearing planets because their habitable zones were assumed to be too close to the star. However, recent research suggests that planets in these "Goldilocks zones"—not too close and not too far from their host star—could potentially support life.

As recently as the 1920s, astronomers believed all the stars in the universe resided within the Milky Way. This perspective shifted dramatically when Edwin Hubble identified a special type of star known as a Cepheid variable. By using these stars to measure distances, Hubble discovered that many of the so-called "nebulae" were actually separate galaxies far beyond the Milky Way.

If you could take an aerial view of the Milky Way, you would see a central bulge surrounded by four prominent spiral arms. While two-thirds of all galaxies in the universe are spiral-shaped, the Milky Way is classified as a barred spiral galaxy because of the elongated bar structure running through its center. It has two major arms and two significant minor arms, along with smaller spurs. Our solar system resides in one of these spurs, the Orion Arm, situated between the larger Perseus and Sagittarius arms.

The Milky Way is not a static structure; it rotates continuously. As the galaxy spins, its arms and the solar system move through space. Our solar system travels at an astonishing speed of approximately 515,000 miles per hour (828,000 kilometers per hour). Even at this incredible velocity, it takes roughly 230 million years for the solar system to complete one orbit around the galactic center.

To grasp the vastness of the universe, consider that the Andromeda Galaxy, our closest galactic neighbor, is about 2.5 million light-years away—equivalent to 15 quintillion miles (15,000,000,000,000,000,000). This immense distance underscores the challenges of discovering intelligent life elsewhere in the cosmos, even as we continue to search for evidence of it.

Barska Straight Spotting Scope with Tripod

Barska Scope - $79.79

For you new star-gazers that don't have a scope, here's the perfect starter telescope.

The Barska Waterproof Straight Spotting Scope is an excellent choice. The optics are crystal clear and it's very light, 2lbs, 10 ounces, even with the tripod attached.

The zooming dial is on the eyepiece, and the focus dial is on the body of the scope. Both are easy to access while viewing.

The tripod is solid, adjustable, and smooth and the scope comes with a lens cap for the front, and a long-screw-on cap for the eyepiece. The carry case has a divided compartment so the scope and tripod don't come into contact with each other. The manual slips in easily and the body of the scope has a solid, rubberized feel. Excellent scope at a great price!

Other Features ...

• Carrying case w/scope and tripod, 14" x 6" x 3"
• 20x-60x zoom magnification
• 100 percent waterproof and fogproof
• Smooth focusing knob
• Fully-coated optics
• Includes pan-head tripod and soft carrying case

Carl Sagan

Carl Sagan was an astronomer, astrophysicist, cosmologist, author, science popularizer, science communicator, in astronomy and natural sciences, and a Pulitzer prize winner. He spent most of his career as a professor of astronomy at Cornell University where he directed the Laboratory for Planetary Studies. He published more than 600 scientific papers and articles and was author, co-author or editor of more than 20 books. He advocated scientifically skeptical inquiry and the scientific method, pioneered exobiology and promoted the Search for Extra-Terrestrial Intelligence (SETI).

Here's the gist of what he stated in a 1966 interview. "Many of the stars in the sky have planetary systems. We know enough now about the origin of life to appear likely that life arises naturally on the vast bulk of these planets."

"It's possible but by no means certain that life, on many of these planets, evolves into beings which are advanced as we, or more advanced. I don't see any reason why we can't imagine that there's civilizations thousands or millions of years in advance of ourselves, capable of technical feats that we can hardly imagine. The real belief in flying-saucers is much easily obtained if you look at the contact myths. Several hundred people in the U.S. who claimed to have had personal contact with the inhabitants of flying saucers that have landed. If you examine these myths you will find there are some peculiar regularities."

The inhabitants of saucers are benevolent, really concerned for our well-being, they are omnipotent - extremely powerful; omniscient - extremely knowledgeable, and they often wear long white robes. This combination is something you hear in other contexts; this isn't science, this is religion. What I suspect is happening is this: we live in very unsettled times. It used to be possible to believe in a personal, benevolent, powerful, all-knowing God, who cared about individuals, who you could pray to. But now, there are very few people who believe that."

from AmazingUniverse.info

Destroying the Ecosystem

The 11th Hour is a documentary from Leonardo DiCaprio about the state of humanity and the world. Co-directors Leila Conners Petersen and Nadia Conners conduct interviews with some of the world's leading scientists and creative thinkers in a film that asks whether or not it's too late to avoid the ecological disaster that looms ominously on the horizon.

In addition to exploring how the human race has arrived at this crucial point in history, conversations with 50 leading thinkers, scientists, and leaders including former Soviet prime minister Mikhail Gorbachev, world-renowned scientist Stephen Hawking, and sustainable design experts Bruce Mau and William McDonough to find out just what humankind can do about the most pressing issues of our time.

Homo sapiens Sapiens is an incredibly young species. We came very late in the calendar year of the Earth. The Earth calendar started January 1 and now we're Dec 31st. We got here 15 minutes before midnight on Dec 31st and all of recorded history as gone by in the past 60 seconds.

There is a fundamental illusion in the world that someone we are separate from nature. The reality is that we are part of nature, in fact, we are nature. This is the fundamental misunderstanding in the world that is causing so much havoc. Our culture is built on the assumption that we are the superior life form on Earth; that we are separate from all other life forms; that we've been given dominion over all other life forms.

To think that we are separated from nature is a thinking disorder. You can't be separated from nature, why we think that way is what's interesting. What happens in the mind that likes to think it's separated from nature? We are living in total disharmony with the planet. We're exploring space, which is a good thing, but our explorations do not affect our attitudes. Attitudes that are based on selfishness, the economic situation, and politics. How many governments in the world have taken the environmental crisis for what it is? Very few, and certainly not the United States.

from AmazingUniverse.info