Wednesday, May 31, 2006

Refracting Telescope: Hans Lippershey's Invention

The Galileo telescope, which is a refracting telescope, is not the first scope to be invented. As everybody knows, from the stargazing newbie to the high school science geek to the serious astronomer – Galileo Galilei did not invent the telescope. Nonetheless, Galileo's telescope was a better and much improved version of the Dutch-invented refracting telescope.

And although he was not credited for the scope’s invention, he nonetheless provided a serious approach to astronomy and stargazing with his own invention. Galileo actually is the major contributor to the development and advancement of modern astronomy.

The inventor of the first scope was the Dutch lens maker Hans Lippershey in 1608. And I believe he deserves the credit, otherwise Galileo Galilei would not have a model from which he can pattern his own refracting telescope. He was a native of Germany who migrated to the Netherlands. He applied a patent for his invention but did not receive it. However for his efforts, he was generously compensated by the Dutch government in exchange for the copies of the designs of his invention.

Actually, Hans Lippershey’s refracting telescope is a simpler, much cruder than the Galileo telescope. Lippershey’s is made out of two lenses, the eye lens and the primary lens. In his application for patent, he intended his newly invented refracting telescope to be utilized for military purposes.

In honor of Hans Lippershey’s contribution to the science of astronomy, a crater of our moon was named after him (Lippershey crater).

Still the Galileo telescope is one major achievement which helped Galileo Galilei earn the title Father of the modern astronomy.

Wednesday, May 24, 2006

Reflecting telescope: Newtonian Telescope

Scientist Sir Isaac Newton (1643 - 1727) of Great Britain invented his own version of the telescope, which is a kind of reflecting telescope. This telescope of Newton utilizes two mirrors, one of which is parabolic in shape while the second is diagonal.

The parabolic mirror reflects an image to the diagonal second mirror. The image is then reflected by the diagonal mirror to an eyepiece which is mounted to the side near the top of the telescope tube. Newton’s use of the mirrors to focus light instead of lenses solved the problem of chromatic aberration. Chromatic aberration is the effect that occurs when light goes through a lens and colors were focused on different places, the result of which would be colors around the image.

The Newtonian telescope has one disadvantage – it suffers from instances of coma. Coma is an aberration that is off-axis in nature, meaning images flare away from the axis of the optics. Today, if your amateur telescope is Newtonian and you need to correct the coma – there are available lenses to bring back clarity and vividness of images. Check knowledgeable scope dealers in your area.

The Newtonian telescope is the simplest of all reflecting telescopes. Newtonians are indeed ideal as amateur telescope for stargazing newbies because it is relatively inexpensive, but still a very effective tool for astronomical endeavors.

The Newtonian is so simple that it is quite easy for amateurs to build a telescope of this type. Even the mirrors, especially the primary, can be built with quality by hobbyists.

Thursday, May 18, 2006

Refracting Telescope, Newtonian Telescope and Schmidt Cassegrain Telescope: The Differences

Let us enumerate the differences between the Refracting telescope, Newtonian telescope and Schmidt Cassegrain Telescope. Hopefully this will help astronomical and stargazing newbies to decide what kind of amateur telescope they would like to have.

Refracting Telescope

Galileo’s version of his telescope is a refracting telescope – and it was during its invention that astronomical pursuits are put to a higher level.

The refracting telescope's lens is convex, meaning it is thicker in the middle than its edges. It is for this reason that the light which passes through the edges are more bent than in the middle, with the lens gathering all the light to go to a focal point – the point where the image is formed.

One disadvantage of refracting telescopes is what we called chromatic aberration – which basically means the all light that go through don’t focus on a single point, making the image blurred. A specialized lens can be used to counteract the effect of chromatic aberration and make the images more vivid.

Newtonian Telescope

Named after its inventor Sir Isaac Newton. If you are a newbie in need of an amateur telescope – this is the best telescope for you. As a beginner telescope, the Newtonian is quite cheap but still very effective. It has a parabolic mirror that focuses an image to a diagonal. This diagonal sends the image to an eyepiece on top of the telescope tube.

One disadvantage of Newtonian telescope is what we call Coma, an aberration in which the image is set off the optical axis. You are experiencing this defect if the stars you are observing are having tails like that of comets, either flaring away from the axis or pointing toward it.

The Newtonian is the simplest of all reflecting telescopes.

Schmidt Cassegrain Telescope

An invention by German scientist and astronomer Bernhard Schmidt and French Cassegrain.

Schmidt Cassegrain is a combination of the refracting telescope and reflecting telescope, extracting the best qualities of the two. Schmidt Cassegrain is currently a favorite instrument for astronomic photography.

This telescope has a corrector that is intended to minimize if not eliminate spherical aberration. It also has primary and secondary mirrors – with the primary mirror having a hole through which the light reflected by the secondary mirror passes.

Aside from an excellent telescope for astrophotography, the Schmidt Cassegrain telescope is one of the most popular among amateur astronomers.

Thursday, May 11, 2006

Advice Before You Buy Telescope

If you are a stargazing hobbyist, a science student, or a someone who's in a serious career as an astronomer, you definitely would be particular with the instrument of the trade (or science for that matter) - your telescope.

You want your beginner telescope to be the best telescope, whether it's reflecting or refracting, or a space telescope. You want the best high-quality lens or mirror for excellent light gathering and resolution which in turn will provide you with magnificent views. You want your telescope to be very easy to set-up and have a reliable telescope mount for every possible movements.

If you want these qualities for a telescope, I have to go to a reliable and knowledgeable telescope dealer who knows the best unit that will suit your astronomy and stargazing requirements. Remember, never go to a discount store or a department store when you decide to buy telescope.

Now, before you buy telescope - the budget is one of the major considerations.

If you're into stargazing and astronomy seriously and you think that it is going to be a lifelong commitment, then it is best that you make a good investment. If you decide in buying an expensive telescope but with all the best specifications put in - it is best to consult your telescope dealer.

It's simply a wise investment to spend a little more cash for an A-1 telescope and enjoy your hobby to the fullest as possible.

Scope City is one of the telescope dealers that you may want to ask information regarding which beginning telescope is appropriate for your need.

Remember, never buy telescope from the discount or department store.

Don't scrimp on an endeavor or hobby that you would like to put your heart into and excel in.

Who knows, you may just be able to accomplish the next best astronomical discovery - all because of your excellent beginner telescope.

Have a great stargazing!

Related Post: On Buying a Starter Telescope

Tuesday, May 09, 2006

Building a Telescope

When you have decided that you want to start a stargazing hobby, the first thing that comes to mind is – where to I get my telescope. But with a limited budget to buy a beginner telescope, how can you acquire that one important gadget? Checking out the magnificence of the heavens cannot be without a scope in hand.

You have two options. Either you a buy a telescope. Or take the adventure of building telescope.

Then you finally thought: indeed, why not build your own telescope! A simple amateur telescope for yourself. A simple one would be that with no frills and unnecessary accessories. Just a basic but amateur telescope that is working fine. Definitely that would be more okay and agreeable to your limited budget.

How do you go about building telescope? Almost anyone can! You can build your own even if you are a total first timer in this hobby of stargazing. And with no prior experience in assembling.

Yes, you can build your own telescope even without seeing or using one in your whole life!

You can build an 8 or 10-inch Newtonian or a 4-inch Dobsonian scope. Whatever it is you want, it’s just easy to build your first beginner telescope.

Here is one resource that is very helpful to get you started in your quest to build your own telescope. Just remember to follow instructions properly and use the appropriate materials and telescope components. Consult and buy telescope components to the reliable dealers and retailers in your area.

Now with your beginner telescope, you can see heavenly objects more than when with just your naked eyes. You can now observe objects that are farther and fainter. Mars or Jupiter. Or even Jupiter’s moon. Pluto. Maybe another galaxy. Or a quasar perhaps.

So, with the resourses on hand, building telescope is quite easy. I know you can hardly wait to gaze up the heavens with your very own amateur telescope. Good luck with your scope-building!

Sunday, May 07, 2006

Telescope Mount

Many of you must already have your amateur telescope or astronomical telescope. Some must have plans to buy telescope, whether be it a simple beginner telescope or the best telescope there is.

One important advice before you buy telescope: seriously take into consideration the mount of your telescope.

Telescope mounts are an important part, mainly because mounts provide stability to the telescope, preventing the telescope from wobbling.

Whether you have an amateur telescope or the most professional telescope in use, you must see to it that it has a stable and reliable mount in order for your telescope to work at its best.

You also must do adjustments and movements to your telescope if you want to gaze at objects at different sections of the heavens. Such adjustments and movements on the telescope should be done without you worrying that it may fall or topple from its position.

A Mount is indeed necessary as a support to your telescope. Mount steady it up and keep it firmly in place.

Now that we have reiterated the importance of telescope mounts, let us discuss the two types of mounts:

Altazimuth Mount

1. The simplest, easiest-to-use mount.

2. The compatible mount to the Dobsonian Telescope.

3. With the Altazimuth, your telescope can be moved up and down (such movement is called altitude), and left and right ( called azimuth), hence its name.

4. It is a reliable mount, quick and easy to set up, and very firm and stable.

Equatorial Mount

1. This is the type of mount that has its axis pointed toward the North Celestial Pole.

2. The primary purpose of the Equitorial Mount is to track or match the movement of the stars.

3. This mount is perfect for long exposure photography because your telescope with move along with your target object.

4. Just make sure you acquire an excellent motor for your axis to make the most of your astrophotography session.

Equitorial mount comes in varieties -

Fork Mount: motorized mount that is best for short tube catadioptric scopes.

German mount: used for refracting scopes due to their lengthy tubes.

Goto mounts: (also Goto telescopes) has motors on all axes, and are so-called because they can be “commanded to go to” a celestial object.

Whatever may be the mount that you are using, make sure that is compatible with your amateur telescope or astronomical telescope to achieve the fullest stability for your telescope. Surely, with this taken care of, you will enjoy a wonderful stargazing!

Friday, May 05, 2006

Beginner Telescope: Using it the Right Way

We all love our beginner telescopes, whether it be a simple amateur telescope or the best astronomical telescope. So naturally, we also want to handle and use our telescopes properly - in a cautious way - to avoid damage especially to the telescope’s mirrors and lenses.

If you bought your beginner telescope in a reputable telescope dealer (and not from the department store like I always advise), you definitely got a unit that’s A-1 in quality, no defects, and perfect for your needs as a hobbyist or as a budding astronomer.

And if you have plans to buy telescope, do not buy from the department store but instead go and buy from the telescope manufacturers and dealers. This is their field of specialty so they know what's the best telescope for you.

Now, it’s all up to you to maintain the perfect condition of your telescope. You can either leave it out there in the gardens and be at the mercy of the elements. Or you can go to the extent of constructing a protective “home” for your beginner telescope whenever it is not in use.

It’s really your choice, but my bet is – everyone of you guys would want to give the best care for your starter telescope.

The following are a few simple caring telescope tips:

Choose the safest place on where to set up your telescope – one that is safe, with a firm ground on which to have a stable mounting, and a place that is free from any obstruction of the view. Claim this place as your own stargazing sanctuary.

Of course, if you want to build a protective steel cage for a telescope house, it’s ok but kind of like extreme. The next best thing is to purchase a covering that would protect your beginner telescope, especially from dust, moisture, and other elements which might otherwise damage the very delicate telescope lenses and eyepieces.

Of course, if you have the perfect setting up place for your telescope, you must also assign the perfect hiding place when not in use, place that’s out of reach of your kid brother, pet dog, or even crawling ants and other insects.

Speaking of your kid brother – he will definitely insist on you letting him use your starter telescope. Well, let him use it – but with your assistance of course. It’s your telescope - so you took time to read the user’s manual, you check of the internet for further caring and maintenance tips. It is best to impart this knowledge to your brother the first time he uses it, this will make him realize the importance of proper use and care. And that you mean it, otherwise you’ll keep him a light-year away from your telescope. Hopefully next time, you may be able (albeit reluctantly) to let him use your telescope on his own.

Remember to apply these telescope tips – your starter astronomical telescope will surely go a long, long, way.

Stargazing is a such a fantastic hobby. Every night, we go out there and always seem to see new great views in the heavens. This in partner with our beginner telescopes.

Related posts on telescope tips:

Your Starter Telescope: Hints on Getting the Most from it

Your Starter Telescope: Additional Tips on Proper Care

Tuesday, May 02, 2006

Barringer Crater


Here is the photograph of the Barringer Crater or the Meteor Crater (which I mentioned in an earlier post) found in Arizona. The picture was taken by the Landsat 4 Satellite. This crater is 1,300 meter in diameter, 570 feet deep. Don't you think it would be nice if I can go down the crater, and install my beginner telescope in the middle of it. Just me stargazing the clear heavens with my beginner telescope in total serenity.

Definitely awesome!

Some facts about the Barringer Crater:

1. The Barringer is the most famous of all craters existing in our planet.

2. The meteorite which impacted and created the crater about 50,000 years ago is a metal meteorite. The impact produced a gigantic explosion enough to kill immediately all living things within the radius of 5 kilometers.

3. Don't you think it should be called Barringer Meteorite Crater? Meteors who come to contact with the earth's surface are called meteorites.

4. The crater was actually bought by an engineer, Daniel Barringer, and his company Iron Standard Company in the 1900's, hence the name.

Happy viewing with your beginner telescope, whether you're in the middle of the Barringer Meteor Crater or not!

Source of Photograph: NASA