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Friday, September 5, 2008

How to Be an Astronomer

So, you have an interest in astronomy and space and you think you want to be an astronomer. This article will show you the steps you have to take in order to turn your amateur astronomy hobby into the career of a professional astronomer.

What is an astronomer and what do they do?

This may seem like a basic question, but it’s a good place to start. Just because you have an interest in astronomy doesn’t necessarily mean that becoming a professional astronomer is right for you.

An astronomer is a scientist who spends a great deal of time studying and observing the behavior of stars, planets, and galaxies as well as lots of other celestial objects. To be an astronomer, a person must earn a doctorate degree and have extensive knowledge of mathematics, computer science, and physics.

Even if you meet these difficult standards and get such an education, your journey toward becoming a professional astronomer is only half over. The competition for jobs in the field of astronomy is extremely fierce.

What you need to do to get started

Try to learn as much as you can about the field of astronomy. The library is a great place to find all sorts of information on the topic of astronomy. More importantly though, it’s absolutely free.

Another thing you should do is find out if there is an amateur astronomy club in your local area. Meeting other people who are knowledgeable about astronomy is a great way to learn things about astronomy that you just can’t learn from a book.

If there is an astronomy observatory near you, then pay them a visit. Observatories are another fantastic way to introduce yourself to the field of astronomy. You may even be able to speak with a professional astronomer at an observatory. There is no better way to research a career field than by talking to someone who is already working in that field.

Lay the groundwork in high school

Try to take as many mathematics and science courses as you can while you’re in high school. You should complete pre-calculus, chemistry, and physics by the time you graduate.

Moving on to college

Once you are accepted into a college, you should choose physics or astronomy as your major and try to carry at least a 3.0 grade point average. A B average is is the minimum GPA accepted by many graduate astronomy programs, so you’ll want to get the highest grades you possibly can while you’re an undergraduate.

Excellent writing skills

Another area to make sure you’re highly proficient in is writing. As an astronomer, you’ll write many articles related to astronomy and space. If you want them to be published in respected publications, the quality of your writing has to be top notch.

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Astronomy Binoculars - Should You Buy Astronomy Binoculars?

Astronomy is a fascinating concept that people of all ages can enjoy being a part of. Having the right equipment for astronomy is very important because it will affect what you are able to see. One good item to invest in is astronomy binoculars. They are very affordable and you will be able to see amazing views of various celestial bodies in the sky with them.

Keep in mind though that astronomy binoculars are intended to offer you a view of various objects out there including the moon, constellations, and comets. If you want to see details of the planets or the crater that appear on Jupiter you won’t be able to do this with only astronomy binoculars. You will need the power of a good telescope.

Many astronomy binoculars have extended magnifiers on them. This is to compete with the many models of telescopes on the market. These are more expensive than the basic ones but you may find they are worth it. They will help you decrease the perceived distance between you and the object.

Some of the best models of astronomy binoculars are made in foreign countries. They are generally found for a lower cost as well. To help ensure your astronomy binoculars will last a long time purchase a set that have coated lenses as well as weatherproof. Some of the best astronomy sites can be viewed in the rain or with moisture in the air but you don’t want it to damage your equipment.

Some models of astronomy binoculars are made to be so durable that they come with a lifetime warranty. You may have to pay more for such a warranty but it is well worth not having to pay for another set of astronomy binoculars again.

Another good investment for those who enjoy astronomy is a tripod. This allows you to have a stable place to star gaze from, especially if you plan to do so for a long period of time. Even the most experienced astronomers can get tired from the position of looking straight up for hours at a time.

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Thursday, September 4, 2008

Novice Guide To Buying Your First Telescope

Space telescopes are amazing instruments. Looking up to the sky on many occasions deep down you want to soon see more. A shining glimmer of light from a star is not enough, we want to see the beauty the universe contains. Your first astronomy telescope can be a blessing or a curse! Read my latest article on finding the right first astronomy telescope for your home.

There is a couple of things to clarify before we take a deeper look at what kind of planet telescope will be right for your needs.

1. When you look through a planet telescope it will be in shades of black and white.

2. The pictures on the planet telescopes box is taken by a professional astro-photographer.

Think of the planet telescope box for your first astronomy telescope as the pictures from fast food restaurants. The picture looks amazing in the picture, but the result is less than imagined. This can deter people thinking that planet telescopes are not what they make out and that they should decide not to buy a first astronomy telescope. This is not the case, after all we still love the fast food. Your first astronomy telescope will still bring you amazing sights which are breathtaking.

One thing to keep in mind is the price and quality factor. In the last part I gave you an example of a fast food chain and the pictures. Now if you purchase your first astronomy telescope for $100 or less, than realize that the quality of your first astronomy telescope will not satisfy your desire to see the universe.

Those first astronomy telescopes selling for less than $100 are great for looking at the moon, but will prove no use for any deep space viewing. The key to having the best first astronomy telescope is to make sure your first astronomy telescope has a strong mount, otherwise the image will shake everywhere, and you will not see much.

The best option is to go for a $200+ planet telescope for your first astronomy telescope. The price determines quality with planet telescopes whether it is your first time planet telescope or you are a seasoned planet telescope user. And the most important parts that need quality is the planet telescope mount, planet telescope lens, and planet telescope mirror.

The main items to look at when buying a planet telescope are the two numbers that will tell you how well it is expected to work. For a great first astronomy telescope, a listing of 20X50 is about average. This means the magnification will equal 20 times what you see with your eyes and the 50 is the width of the length, which is what determines how much light is gathered. The more light the better the image will be visible in the dark and for astronomy, all star gazing is typically done after dark.

A lot of the cheap planet telescopes try to sell you on fancy gadgets. They look good to have on your new first astronomy telescope, but the truth is that these kind of features will be of no use. Consider on a $100 first astronomy telescope that comes with loads of fancy gadgets, most of the money is going on those features. All you need to get started in astronomy with a first astronomy telescope is to make sure more of your money goes on the planet telescope mirror, planet telescope mount, and planet telescope lenses.

One last thing to consider before you buy your first astronomy telescope make sure you take into account the space your first astronomy telescope will need. It needs space to move around ;>. Good luck with buying your first astronomy telescope.

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Radar Astronomy-The Ins and Outs of New Technology

NASA’s Jet Propulsion Laboratory, using technology similar in some ways to that used to power microwave ovens, is detecting and imaging asteroids by beaming radar signals toward the objects, then collecting and analyzing the reflected waves. Radar astronomy doesn’t require a night sky or a space probe to find and analyze the objects–just the world’s largest dish antennas. Radar pulses are beamed toward selected targets and the reflected “echoes” are collected and analyzed to reveal information about surface features, rotation, as well as internal structure and density of the asteroids.

Closer targets provide better signals and therefore more accurate information from which three dimensional models can be imaged, and the rotation of the asteroid can be defined. A good signal can enable a spatial resolution of less than 10 meters. Echoes from more than 190 near-Earth asteroids have been detected, showing great variations in structure and composition, with no two alike. They can be stony, metallic, smooth or coarse in texture, traveling alone or with satellites, and come in an endless variety of shapes and sizes.

Arecibo Observatory in Puerto Rico, with its 100-foot diameter telescope, and the 70 meter Goldstone antenna, located in the Mojave Desert of southern California, are the only two places in the world performing effective radar astronomy. Each complements the other, making an effective asteroid detection partnership. Researchers, using the antennas of Arecibo and Goldstone, were able to observe the near-Earth asteroid 1999 KW4 and determine it to be a double asteroid, or binary, comprised of two rubble clusters orbiting each other. Although the asteroid passes near Earth occasionally, and is classified as a Potentially Hazardous Asteroid, the information provided by the observatories indicated that it will not cross Earth’s path for at least 1,000 years.

Radar astronomy has been shown to be vital for locating asteroids and predicting the orbits of the ones that could pose a danger to the Earth, as this form of asteroid detection and analysis has proven to be much more accurate than observations made by optical instruments. Radar astronomy would also provide more accurate information about any approaching comets, including their composition and projected path.

Future technology is planned which will make it possible to discern surface features on asteroids with four times the amount of detail than is possible now. It is also suggested that before any space mission to an asteroid, the necessary pre-flight, scientific analysis will depend upon the information gathered by radar astronomy.

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Can a Black Hole Lose its Clothes?

A black hole is a mass that is so compact that it disappears inside an invisible surface called an event horizon. The actual mass is compressed into a mathematical point, called a singularity, sitting at the center of the event horizon sphere. The term event horizon comes from the fact that no event happening inside it can be observed from the outside.

Event horizons are a direct consequence of Einstein's theory of general relativity. The reason why no events on the inside of an event horizon can be observed from the outside is that gravity is so strong there that nothing can escape from within, and that includes light and any other form of signal.

The event horizon effectively "dresses" the singularity at the center of the black hole and nature is apparently very reluctant to get rid of these "clothes". In 1969, Sir Roger Penrose proposed the cosmic censorship hypothesis, which was also stated as: "nature abhors a naked singularity".

So how can a naked singularity possibly be formed and how does nature prevent it from happening? In 1963 Roy Kerr, a native New Zealander, discovered an exact solution to Einstein's equations of general relativity, representing the space-time around a rotating (spinning) black hole.

Because most (if not all) stars rotate, it is thought that most black holes that have formed from the collapse of massive stars must be spinning. And just like a ballerina that spins faster when she pulls her arms in towards her body, a star collapsing under its own gravity will spin faster the more compact it gets.

Every ordinary object has a maximum rate of spin, where the centrifugal forces tend to overwhelm the binding force between its molecules and/or atoms. Exceed that spin rate and the object breaks up and may fly apart. The Kerr solution shows that a black hole also has a maximum spin rate, above which it may destroy itself.

Because of the immensely strong gravity of a black hole, it cannot just break up and fly apart. Should it be able to spin faster than the maximum theoretical spin rate, its "clothes" (the event horizon surface) may shrink to zero size and essentially disappear.

This means that the "clothes" become part of the central singularity of the black hole, essentially leaving it "naked". For this reason, it is called a naked singularity, the kind that nature apparently "abhors".

There is some uncertainty amongst scientists as to whether singularities, naked or not, actually do exist. It is possible that quantum mechanical effects may prevent such bizarre things to exist in nature.

In any case, if singularities do exist, the Penrose cosmic censorship may, by means of a compulsory event horizon, forever prevent their exposure to man's observing telescopes…

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Monday, September 1, 2008

New Planet, Red Star - "We Can Go There!"

Tired of the same old screaming heads on network and cable television? Me too. Do you really need movies about bestiality? Here is a recent CNN.com list of headlines that would send my dog running, and she’ll watch anything.

Senate Passes Iraq Bill Bush Will Veto (Yawn-What a Surprise)

Rosie O'Donnell leaving “The View” (Like, We Care)

Sheryl Crow's Toilet Paper Square Just a Joke (Anyone Laughing?)

Battle of the Baldwins (Another War of the Roses?)

Movies: “Zoo” (The Best? of Hollywood)

When The Stars Come Out

A famous astrologer opines that fiery Kim Basinger, a Sagittarius, and mad dog Baldwin, an Aries “create fireworks together.” I'd say more like the big bang. Apparently the volatile duo’s Sun signs make them “combustible.” Adding insult to injury, according to the astrologer, both birth charts are “seriously situated in Mars.” Isn't he the god of war? Hmmm.

An Earth-Like Planet

With Washington fiddling while Iraq burns; young people murdering young people in America, Americans dying in Iraq and Afghanistan, the one news story that lifts me out of the doldrums of despondency is a newly discovered “earth-like planet.” Although astrology is empirically unproven, and the science of astronomy is empirical, the sad Baldwin/Basinger affair seems an acceptable segue out of star gossip and into something a little more uplifting within the realm of the universe.

A Star is Born

I must have relatives living in another solar system because I’ve been a stargazer all my life. By age nine I’d memorized all the planets’ distance from the sun, and the locations of the constellations. Together with a few classmates (we were the Comets), the Hayden Planetarium became my hangout on Saturday afternoons. Their Zeiss projector was my gateway to the cosmos, from the beginning of time to the present. It put on a better show than any movie theater, well almost. Favorites are Jodie Foster’s “Contact,” and Jeff Bridges’ romantic “Starman.”

New Star in Town

The discovery this week by a European team of astronomers of a new planet in the constellation of Libra gets my adrenalin pumping. Apparently the newly found planet, given the unromantic name, Gliese 581c, orbits its red dwarf star, which is only about 7 million miles away from it. A red dwarf is a dim star. Some other dwarfs are even dimmer and appear brownish-red. By comparison, our own young brilliant sun star is safely over 92 million miles from planet earth and isn’t expected to become a red giant for another 5 billion years. So there's ample time before calling Homeland Security about the incinerating results of that big bang.

“We Can Go There”

We’re told that Gliese 581c has a surface temperature between 32 and 104 degrees Fahrenheit and it could easily have water. Children being born now, and their children, will be working on this discovery the rest of the century. One of the astrophysicists on the team says the planet is 120 trillion miles from earth and 20 light-years away. “We can go there,” he says. I don't want to dampen the man’s enthusiasm, but we haven’t figured out how to safely make the 35 million miles to Mars and back—supposedly in eight months. But if we stop paying for wars, we can do it and much more to enhance life on our own planet before we do have to leave it.

One Small Step For Man

In any case, the fact that earthlike temperatures and water may exist on Gliese 581c, may also mean life exists there; maybe not life as we know it, but modern man (homo sapiens sapiens) has proven his/her adaptability. And that’s what makes this whole business of space travel and colonization so fascinating to people with their heads in the stars. I wish that astronomer/astrobiologist Carl Sagan could have lived to experience this moment, another of the best of man’s accomplishments. You have only to spend a few moments looking up at night with even a small telescope to know the man was right.

“Science is not only compatible with spirituality; it is a profound source of spirituality.”—Carl Sagan

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Homeschool Astronomy on a Budget

Initially in astronomy, there is not a huge financial investment. Just go outside and look up. Instant success. You see stars.

But then, there comes a thirst for more. What are the stars made of? Why do they move in the sky? And what’s all this winking and twinkling about? Questions you haven’t thought of since you wore Superman underwear. These worthy inquiries are easily answered in a trip to your local library.

Then it really happens. You find out your very own town has an astronomy club. "Come see the stars!", they entice you! "Free Star Party this Saturday!" Armed with a thermos of hot cocoa and cookies your wife made, you tramp up Star Party hill. And you see it all - not just the stars and galactic nuclei, but all those TELESCOPES.

WOW.

Your wife is not happy about trading the car for a telescope. Call her crazy, but a telescope doesn't pick up the groceries or take kids to ballet. In fact, it's a gadget to look at things that have been around since before either of you were around. You’re just all-fired up on doing it now. And yes, most of those sparkly things up there will be up there when you retire, so why not just wait until then?

"Because the purpose of life to experience happiness, which can only be experienced in the present moment," explains the Dalai Lama, quite patiently.

"But the Dalai Lama does not have four children and two mortgages," your wife counters. So what are you to do?

Astronomy club telescopes are available for members, but what if you want something of your very own right now? (We are, after all, Americans.) And you want to share astronomy with your kids, and you're not likely to share an expensive telescope with those grubby hands. There must be a happy alternative. But what?

Go get a raft. The inflatable kind you have lurking somewhere in your garage already. Set it up on the grass, and pull out a pair of binoculars. A good pair. Add cocoa and cookies, and you have an instant star party worthy of any amateur astronomer.

How to pick a good pair of binoculars? Here are some ideas that may work for you (excerpted from Backyard Astronomer’s Guide by Dyer and Dickinson):

Larger main lenses mean brighter images, but for most people, a 50mm lens is a practical handheld limit. Binoculars with a 7mm exit pupil are easier to bring to correct position in front of the eye, an advantage for young people and beginners of any age.

Higher magnification means better resolution, but it also means more stringent optical-quality standards to produce good images. It also results in amplified jiggling during handheld operation. This factor alone limits binocular magnification for handheld astronomical viewing to 10x.

Put it all together, the most popular sizes are 7x50 and 10x50. If you prefer smaller and lighter, go for the 7x42 or 8x42. Why not just go for the 10x50s, since biggest means best? Well, because aiming and observing through binoculars at night is much easier for some than others. In our experience, 7x50s are much easier to use. On the other hand, 10x50s yield fainter stars and more Moon and celestial object detail. More detail makes sense, but why are dimmer stars more apparent? Part of the reason is that the smaller exit pupil helps avoid the edge-of-eye aberrations (producing sharper stars), but mainly, it is that the higher magnification in effect spreads out the sky background, darkening it in the process.

Roof prism binoculars are more compact than porro prism in sizes under 42, and are generally more costly. For general astronomy binoculars at a reasonable price, we recommend porro prism models in 7x50 and 10x50.

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Homeschool Astronomy - How to Tell Time By the Stars

Let’s practice this during the daytime so it makes sense before you try to impress your friends. Get out a pencil and a sheet of paper.

First, you'll need to find Polaris. Draw a dot in the middle of your paper. Instant star.

Draw a BIG circle around the dot. Now imagine the mirror-image of your kitchen clock imposed over Polaris in that circle. This means 1 is where the 11 usually is, and the 3 is where the 9 normally goes. Draw all twelve digits inside that circle around Polaris.

Now imagine you are looking up at the dark night sky. Imagine yourself finding Polaris. Stare at it. Draw an imaginary line out through Dubhe and Merak (the pointer stars in the Big Dipper that lead you to Polaris). This straight line is the hour hand of the clock (there is no minute hand). This hour hand makes a complete circle around the North Star every 24 hours.

At midnight on March 1, the hour hand points directly to midnight (straight up). When this hour hand moves, it moves counterclockwise. And every 5-minute mark on regular clocks (this is the 1, the 2, the 3, the 6 at the bottom…) represent two hours. So if the hour hand points straight to the 3, (normally the 9 position on your kitchen clock), then it is 6 hours past midnight on March 1. Got that so far? Good. Let’s make it harder.

Subtract 2 hours for every month past March 1. For example, if it is May 1, subtract 4 hours. (Add one hour for daylight savings time.)

Let’s try an example. Imagine it is June 1. Imagine the star-clock is one forth the way past the 1 on your mirrored-kitchen-clock paper diagram. It currently reads 2:30 am (remember it is two hours between the 1 and 2 on the clock). Now subtract 2 hours for each month past March 1. Since it’s June 1, subtract 6 hours. Add one hour for daylight savings time, and you now get 9:30 pm. Cool!

With practice, you will eventually be able to tell the time by the stars in a matter of seconds (trust me). And you'll no longer wonder “What time IS it?” and be scolded by fellow astronomers as you pull out a flashlight to glance at your watch (albeit red). And it is a nifty ooooh-ahhhh trick with kids-at-heart everywhere.

Since 1996, Aurora Lipper has been helping families learn science. As a pilot, astronomer, engineer, rocket scientist, and former university instructor, Aurora can transform toilet paper tubes into real working radios and make robots from junk in the back desk drawer.

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