The last lunar eclipse of 2012

 A penumbral eclipse of the Moon will occur on November 28-29, 2012.

A penumbra refers to a partially shaded outer region of a shadow that an object casts. A penumbral eclipse occurs when the moon passes through the faint penumbral portion of the earth’s shadow.


The lunar surface is not completely shadowed by the earth’s umbra (darkest part of a shadow). Instead, observers can see only the slightest dimming near the lunar limb closest to the umbra. The eclipse may be undetectable unless at least half of the moon enters the penumbra.

The last lunar eclipse of 2012 is a deep eclipse with a magnitude of 0.9155. It should be easily visible to the naked eye as dusky shading in the northern half of the Moon. People in Alaska, Hawaii, New Zealand, Australia, and Most of Asia can see the eclipse!


Key times for the lunar eclipse: 

Penumbral eclipse starts –12:14:58 UT

Greatest eclipse – 14:33:00 UT

Penumbral eclipse ends - 16:51:02 UT

Please Share This Opportunity So that Everyone Can Enjoy It. :)

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How to Take Star-Trail Photographs

Star-trail photographs are a fantastic way to capture the beauty of the stars and create an abstract photograph. It’s also a great way to get into astrophotography if you don’t have a telescope.
Equipment

First of all, you need to have a good camera. While any camera that can do time-exposure will work, D-SLR (digital single-lens reflex) models will give you better results. The shutter needs to be able to stay open for a significant amount of time without the batteries draining. The best type of lens to use is a wide-angle lens, such as a 35mm at 20-50mm focal length.

You also need a tripod for your camera. Make sure it is sturdy enough so that it won’t get disturbed or knocked over by the wind – any movement will create wiggles in your star trails.
Finally, you need a cable release so that you can take the photo without moving the tripod. However, some cameras will let you use the self-timer with a long exposure as well.
Set-up

Star-trail photos vary widely depending on the composition of the photo, exposure time, and focal length. You will probably end up experimenting with different settings to see which type of star-trail photos you like the best. Here are some tips to get you started.
On a digital camera, use an ISO between 400 and 800. This will take in the brightness of the stars without keeping the rest of the photo dark. For very long exposures, you may try using a lower ISO. If you’re using film, use slow or medium-speed.

Set your aperture to f/4.0 or f/5.6 This will reduce the glow of the sky, especially from light pollution, and bring out the light of the stars. You should also try to take the photo in a dark place to reduce light pollution.

Try to include other stationary elements in your photo, as this will give it perspective and make it more interesting. Everything from rocks and trees to houses or a simply horizon can work.
Finally, use fully charged batteries and make sure they will last for the length of your photo exposure.

This article was written by Madeline Barbour. She is an experienced photographer who owns the site How to Become a Photographer.

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According to Lupu Victor, Astronomical calendar-astronomy events in 2012

This is how the much debated calendar of year 2012 will look like.

03.04 January 2012 - Quadrantids. Quadrantid meteor shower, get to have up to 40 meteors per hour, usually on 3 and 4 January, but may be visible on 1-5 January. The highest rate of meteors per hour took place in 1932 (80/ hour). The best time for observations is a dark place after midnight. Meteors radiate from the constellation Bootes, close to the North Star.
The source of this meteor shower was unknown until December 2003 when Peter Jenniskens of the Ames Research Center (NASA) found evidence that meteoroids come from 2003 EH1 , an "asteroid", which is probably a piece of a comet which collapsed 500 years ago.

05 January 2012 Earth reaches perihelion at 1:00UT, at a distance of 147,097,202 kilometers from the Sun.

January 9, 2012 - Full Moon. Earth will be between the Sun and Moon, and therefore, the Moon will be fully illuminated as seen from Earth. This phase takes place from 07:30 UT.

January 13, 2012 - Mercury conjunct Pluto, both in Capricorn., And Venus conjunct Neptune, both in the constellation Aquarius (within 1.2 degrees of Neptune).

January 14, 2012 P/2006 T1 Levy reaches perihelion at 0.9 Astronomical Units from the Sun. The Comet Levy passes within 0.2 AU of the Earth, and reach magnitude +7 as it moves through the constellation Cetus in the evening sky
January 23, 2012 - New Moon. Luna will be between Earth and Sun and will not be visible from Earth. This phase occurs at 07:39 UT.

January 31, 2012 - 433 Eros asteroid with a diameter of 33,000 x 13,000, passing in the constellation Sextans. It is a Near-Earth asteroid (NEA), discovered in 1898, the first asteroid that was orbited by a probe (in 2000). It is a S type asteroid size, second after 1036 Ganymede, and belongs to the Amor group.
Eros is an asteroid passing near Mars. Such objects have orbits that may remain there a few hundred million years before the orbit to be disturbed by gravitational interactions.
It is a potential impactor of the Earth, considered to produce a larger crater than the Chicxulub crater from an impact that is believed to be responsible of the extinction of the dinosaurs.

February 7, 2012 - The “Missing Moon phase” month as reckoned in Universal Time, missing 1st Quarter on Leap Day by 21 minutes.

February 7, 2012 - Full Moon. Earth will be between the Sun and Moon, and therefore, the Moon will be fully illuminated as seen from Earth. This phase takes place at 21:54 UT.

February 9, 2012 - Venus conjunct Uranus.

February 13, 14, 2012 -Mercury conjunct Neptune.

February 21, 2012 - New Moon. Luna will be directly between Earth and Sun and will not be visible from Earth. This phase occurs at 22:35 UT.

March 3, 2012 - Mars in opposition. Mars will be closest to Earth and it's surface will be fully illuminated by the Sun. This is the best time to view and photograph Mars.

March 5, 2011 - Mercury conjunct Uranus. Also is the best evening elongation of Mercury for northern hemisphere viewers, at 18° from the Sun.

March 8, 2012 - Full Moon. Earth will be between the Sun and Moon, and therefore, the Moon will be fully illuminated as seen from Earth. This phase takes place at 09:39 UT.

March 14, 2012 - Conjunction of Venus and Jupiter. The two bright planets will be 3 degrees to each other in the evening sky.

March 20, 2012 - Equinox of March. March Equinox occurs at 05:14 UT. The Sun will shine directly on the equator and the days and nights will be almost equal in the whole world. This is also the first day of spring (spring equinox) in the northern hemisphere and the first day of fall (autumnal equinox), in the southern hemisphere.


March 22, 2012 - New Moon. Luna will be directly between Earth and Sun and will not be visible from Earth. This phase takes place at 14:37 UT.

April 3, 2012 - Venus is near the Pleiades at sunset, on a cycle of transits in front of the open cluster occurring every 8 years until 2060.

April 6, 2012 - Full Moon. Earth will be between the Sun and Moon, and therefore, the Moon will be fully illuminated as seen from Earth. This phase takes place at 19:19 UT.

April 15, 2012 - Saturn in opposition.The planet will be closest to Earth and it's face will be fully illuminated by the Sun. This is the best time to view and photograph Saturn and its moons.

April 21, 2012 - New Moon. Luna will be directly between Earth and Sun and will not be visible from Earth. This phase occurs at 07:18 UT.

April, 21.22 2012 - Lyride meteor shower. Lyrids are meteor showers with medium intensity, usually producing about 20 meteors per hour. These meteors can produce bright dust tail that takes a few seconds. Some meteors may be visible between April 16 to 25. The Moon will not light up the sky, and so it would be a good show. These meteors radiate from the constellation Lyra, and their source Comet Thatcher 18611.

April 22, 2012 - Mercury conjunct Uranus.

April 30, 2012 Venus is at -4.5 magnitude, bright enough to be visible in broad daylight.


May,05, 06, 2012 - Eta Aquarid meteor shower. Eta Aquarids usually produce about 10 meteors per hour. The highest intensity usually take place on 5 and 6.
Full Moon will discourage observations. The radiant point is the constellation Aquarius, and the meteors originates from Comet Halley. The best observations are usually to the east after midnight, away from city lights.

May 5, 2012 - Mercury and Saturn in opposition.

May 6, 2012 - Full Moon. - Moon at the perigee, or closest Full Moon of the year, or “Super Moon”. Also, Earth will be between the Sun and Moon, and therefore, the Moon will be fully illuminated as seen from Earth. This phase occurs at 03:35 UT.

May 20, 2012 - New Moon. Luna will be directly between Earth and Sun and will not be visible from Earth. This phase occurs at 23:47 UT.

May 20, 2012 - Annular eclipse of the Sun. It will not be visible in Romania but I mentioned it. It will start in southern China and will move eastward through Japan, North Pacific Ocean and the western United States.

May,21, 22, 2012 - Mercury conjunct Jupiter.

June 4, 2012 - Full Moon. Earth will be between the Sun and Moon, and therefore, the Moon will be fully illuminated as seen from Earth. This phase takes place at 11:12 p.m. UT.

June 05, 06, 2012 - Venus transiting the Sun. This rare event will be entirely visible mostly in East Asia, eastern Australia and Alaska. A partial transit can be seen in progress at sunrise throughout Europe, West Asia and East Africa. A partial transit can be seen in progress at sunset in most of North America, Central America, South and West America . It will not take place again until 2117.

June 12, 2012 -Asteroid 1761 Edmondson transits in front of Jupiter.

June 19, 2012 - New Moon. Moon will be directly between Earth and Sun and will not be visible from Earth. This phase takes place at 15:02 UT.

June 20, 2012 - June Solstice. June solstice occurs at 23:09 UT. North Pole of the Earth will be tilted towards the Sun, which will reach the northernmost position in the sky. This is the first day of summer (summer solstice) on the northern hemisphere, and the first day of winter (winter solstice), in the southern hemisphere.

July 3, 2012 - Full Moon. Earth will be between the Sun and Moon, and therefore, the Moon will be fully illuminated as seen from Earth. This phase takes place at 18:52 p.m. UT.

July 5, 2012 The Earth is at aphelion, or its at the farthest point from the Sun at 3:00 UT, at a distance of 152,092,400 kilometers.

July 9, 2012 Jupiter, Venus & Aldebaran are visible in a tight 1° degree grouping at dawn.

July 14, 2012 Comet 96P/Machholz 1 reaches a perihelion of only 0.12 AU, and may reach magnitude +9.0 as it crosses into the constellation Gemini in the evening sky.

July 19, 2012 - New Moon. Moon will be directly between Earth and Sun and will not be visible from Earth. This phase occurs at 04:24 UT.



July, 28, 29, 2012 - South Delta Aquarids can produce about 20 meteors per hour. Radiant point for these meteors is in the constellation Aquarius.
August 2, 2012 - Full Moon. Earth will be between the Sun and Moon, and therefore, the Moon will be fully illuminated as seen from Earth. This phase occurs at 03:27 UT.



August 6, 2012 - Curiosity rover on Mars.Mars Science Laboratory (MSL) of NASA, is scheduled to land on the red planet on 06 August 2012. Curiosity is an autonomous rover similar to Spirit and Opportunity robots that previously visited Mars. This rover larger, will have more instruments and will perform many more experiments than the previous ones. HD cameras will photograph the Martian surface while other tools will examine soil and air samples and will be in search of organic
compounds.
August, 12.13, 2012 - Perseide meteor shower. Perseids are one of the best meteor showers that produce up to 60 meteors per hour at their peak hours. Radiant point is in the constellation Perseus, and the meteors originates from the tail of Swift-Tuttle Comet.Find a place away from city lights and look to the northeast after midnight.
August 15, 2012 - Mars comes into conjunction with Saturn.
17 August 2012 - New Moon. Moon will be directly between Earth and Sun and will not be visible from Earth. This phase takes place at 15:54 p.m. UT.


August 24, 2012 - Neptune will be in oposition.The planet will be closest to Earth and it will be fully illuminated by the Sun. This is the best time to observe Neptune. Because of its distance, it will appear only as a tiny blue dot.
August 31, 2012 - Full Moon. Earth will be between the Sun and Moon, and therefore, the Moon will be fully illuminated as seen from Earth. This phase takes place at 13:58 UT. Since this is the second full moon in the month, is known as Blue Moon. This rare event only happens every few years.


September 16, 2012 - New Moon. Moon will be directly between Earth and Sun and will not be visible from Earth. This phase occurs at 02:11 UT.

September 22, 2012 - September Equinox.September Equinox occurs at 14:49 UT. The Sun will shine directly on the equator Days and nights will be almost equal in the whole world. This is also the first day of fall (autumn equinox) on the northern hemisphere, and the first day of spring (vernal equinox), in the southern hemisphere.

September 29, 2012 - Uranus in oposition. The blue-green planet will be closest to Earth and it will be fully illuminated by the Sun. This is the best time to observe and photograph Uranus. Because of its distance, it will appear only as a small blue-green dot.
September 30, 2012 - Full Moon. Earth will be between the Sun and Moon, and therefore, the Moon will be fully illuminated as seen from Earth. This phase occurs at 03:19 UT.


October 5, 2012 - Mercury conjunct Saturn.
October 15, 2012 - New Moon. Moon will be directly between Earth and Sun and will not be visible from Earth. This phase takes place at 12:02 UT.
October,21, 22 , 2012 - Orionide meteor shower. Orionids are a meteor shower of medium intensity, which produces about 20 meteors per hour. A good view is in any morning from October 20 to 24. The first Quarter Moon will set before midnight, leaving a dark sky. The best cardinal point to see will be to the east after midnight.Orionids originates from Comet Halley.
October 28, 2012 - Asteroid 13 Egeria occults a +8.1 magnitude star at 00:44 UT , seen from Russia, Europe and North Africa.
October 29, 2012 - Full Moon. Earth will be between the Sun and Moon, and therefore, the Moon will be fully illuminated as seen from Earth. This phase takes place at 19:49 UT.


November 13, 2012 - New Moon. Moon will be directly between Earth and Sun and will not be visible from Earth. This phase occurs at 22:08 UT.
November 13, 2012 - Total eclipse of the Sun. This eclipse will be visible in Romania but only in the extreme northern parts of Australia and South Pacific Ocean. Partial eclipse will be visible in most parts of eastern Australia and New Zealand.
November 17, 18, 2012 - Leonids - meteor shower. Leonids meteor showers are one of the best for observation. You will see about 40 meteors per hour.Leonids have a cyclic peak year every 33 years when hundreds of meteors can be seen each hour. Last time this phenomenon occurred in 2001. Meteors will radiate from the constellation Leo after midnight and the meteors originates from the tail of the Comet Temple-Tuttle.





November 27, 2012 - Conjunction of Venus and Saturn. These two bright planets will be close to 1 degree apart on the eastern morning sky.November 27, 2012 - Mars comes into conjunction with Pluto.

November 28, 2012 - Full Moon. Earth will be between the Sun and Moon, and therefore, the Moon will be fully illuminated as seen from Earth. This phase takes place at 14:46 UT.

November 28, 2012 - Penumbral Lunar Eclipse. The eclipse will be visible mostly in Europe, East Africa, Asia, Australia, Pacific Ocean and North America.

December 3, 2012 - Jupiter in oposition.The giant Jupiter will be on the closest distance from Earth and its surface will be fully illuminated by the Sun. This is the best time to view and photograph Jupiter and its moons.

December 3, 2012 - Mercury, Venus, Saturn form a line 15° degrees long for a triple conjunction in the morning skies
December 12, 2012 - Toutatis asteroid with a diameter of 5 km, passing near Earth. It has an orbital period of almost each four years and is an asteroid passing near Mars, with a chaotic orbit.
The approaching on 29 September 2004, was at 0.0104 UA (4 Moon distances), which was a good opportunity for observation, with a bright Toutatis on 8.9 magnitude brightness.
Most recent approach of 0.0502 UA happened on November, 9, 2008. In the near future will be on December 12, 2012, at a distance of 0.046 UA, and the magnitude of 10. As you can see, this asteroid always returns each time passing closer to Earth, but does not present any danger to these distances. The shortest distance that can ever have this asteroid will be 0.006 UA, which is 2,3 times the distance between us and the Moon (2.3 Moon distances).

December 13, 2012 - New Moon. Moon will be directly between Earth and Sun and will not be visible from Earth.

December 13, 14, 2012 - Geminids meteor shower, is considered by many to be the best meteor shower on the the sky. Geminids are known to produce up to 60 multicolored meteors per hour at their peak. Most usually appear on, or around 13 by December and 14, although some meteors should be visible between 06 and 19 December. They radiate from the constellation Gemini and originates from the asteroid 3200 Phaeton. This year, New Moon will guarantee a dark sky, so it would be a wonderful show. The best observation is to the east after midnight in a dark area.December 21, 2012 - Winter Solstice. The December solstice occurs at 11:12 UT. South Pole of the Earth will be tilted towards the Sun, and will reach the most northern position in the sky. This makes it the first day of winter (winter solstice), the northern hemisphere, and the first day of summer (summer solstice), in the southern hemisphere.
December 28, 2012 - Full Moon. Earth will be between the Sun and Moon, and therefore, the Moon will be fully illuminated as seen from Earth. This phase takes place at 10:21 UT.

By what I have presented here, nothing unusual will happen in 2012 astronomically speaking. There will not be big alignments of planets, and will not come to us the planet Nibiru, therefore, no end of the world will happen. not this time. The year 2012 will come and will pass like any other year. All is known. The only threat that we would have would be a large asteroid that is not detected in time, and that would be on the path of the Earth, or other forces that we have not discovered yet. The rest are just unfounded opinions and speculations.
Otherwise, we have many meteor showers, a transit of Venus across the Sun, and some conjunctions of planets.
For those who like my astro pictures or my articles, it woul be great if you could pay attention on advertising that appear in the blog by a click and maybe one day I could buy a better telescope.

Read more: http://lupuvictor.blogspot.com/2011/10/astronomical-calendar-astronomy-events.html#ixzz1lodm12lu

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Why buy a reflector?

In a word – value. A Newtonian reflector offers more performance for your observing dollar than any other telescope type.
The reflector's large light-gathering area and relatively short focal length can provide bright images of deep space objects that are too faint for any small aperture refractor to see. And the reflector's large aperture can resolve details within those objects with a precision no small scope can match – if the seeing is good.

The penalty you pay for this performance is typically one of large size and weight – although not necessarily one of high cost, as reflectors traditionally cost the fewest dollars per inch of aperture of any telescope type.

The reason? A reflector has only one mirror to grind and polish to a precise curve (with an accuracy of +/-five one-millionths of an inch or better). A refractor, on the other hand, has two to four lenses, with a total of four to eight precisely curved surfaces to shape. And those lenses might have to be costly exotic glass formulations in order to provide satisfactory images. Similarly, a catadioptric scope has three or four curved optical elements to shape to a high degree of accuracy.

All that extra mirror and lens grinding and costly optical glass types in refractors and catadioptrics doesn't come cheap. That makes the one-curved-mirror and one-flat-mirror optics of a reflector the least expensive to make, and hence the lowest in cost per inch of aperture.

For the same amount of money, therefore, you get more aperture with a reflector than with any other scope type. And, all other things being equal, the bigger the aperture, the better the performance. An 8" reflector typically costs 50% less than a quality 4" refractor, and little more than 3.5" catadioptric, but will have four times the light grasp of either.

For purely visual deep space observing, Dobsonian reflectors are very cost effective. With huge mirrors (up to 24" in diameter) to gather light, and inexpensive wood mounts, these new Newtonians have brought about the age of the "light bucket" in amateur astronomy. The deep space observer on a budget has never had it so good.

The astrophotographer will also find that a large aperture equatorial mount reflector is excellent for recording deep space objects in detail, as well as visual observing. (Photography is not possible with an altazimuth Dobsonian reflector.)

The drawbacks of a reflector? There are five – diffraction, coma, size, weight, and added maintenance.

Light diffracted, or scattered, by a reflector's diagonal mirror can reduce image contrast in lunar and planetary observing, masking subtle surface details compared with an unobstructed refractor image. In addition, diffraction spikes on star images, due to the spider vanes that hold the diagonal mirror, can mask faint binary star components and smear globular cluster detail.

Because of the parabolic shape of their primary mirrors, all reflectors have coma – an optical defect in which stars appear triangular or wedge-shaped at the edge of the field. The faster the focal ratio, the smaller the coma-free field. This can be annoying in photos, where the entire field is available for leisurely inspection. It is usually unobjectionable visually, however, since objects of interest are normally kept in the center of the field, where eyes and eyepieces are sharpest and coma is less of a factor.

Since an 8" reflector can weigh up to 50% more than an 8" catadioptric, and its 48" long optical tube is not the easiest thing in the world to manage in an apartment elevator, a large reflector usually requires the elbow room afforded by a suburban environment. Also, since city light pollution almost invariably compromises deep space performance by washing out faint nebulas and galaxies, dark sky observing sites are always recommended with medium to large aperture reflectors. Large aperture reflectors (12"-16" and larger) almost invariably require a minivan or SUV for transport to the dark sky sites they need to avoid being overwhelmed by the effects of city and suburban light pollution. They often also need some friends to help you with the setup of the bulky components. Owning and using a large reflector is more of a lifestyle than it is a hobby.

In addition, unlike refractors or catadioptric telescopes, a reflector requires frequent recollimation or alignment of its optics, and its exposed mirrors mean that periodic cleaning will also be required. However, this maintenance typically averages only a few additional minutes of work per observing session.

These drawbacks aside, for serious visual observing of faint galaxies and nebulas, as well as for more-than-acceptable lunar and planetary observing, you'd be hard-pressed to equal, much less surpass, the excellent price-to-performance ratio of a Newtonian reflector. Reflectors have been a best-seller for over 300 years – and sheer value for the money is why.

REFLECTOR REPORT CARDS
(used in excellent seeing conditions and with no light pollution; adapted from Astronomy Magazine):

E = excellent; VG = very good; G = good; F = fair; P = poor.

Small aperture (3" to 6") reflectors:
Price range: $120-$1000
Portability: E
Ease of setup: VG
Ease of use: VG+
Performance on the Moon: E
Performance on comets: F
Performance on double stars: VG
Performance on galaxies and nebulas: F
Performance on planets: VG

Medium aperture (8" to 12.5") reflectors:
Price range: $400-$14,000
Portability: F
Ease of setup: F
Ease of use: VG+
Performance on the Moon: E
Performance on comets: VG
Performance on double stars: VG
Performance on galaxies and nebulas: VG
Performance on planets: VG

Large aperture (13" and larger) reflectors:
Price range: $1200-$36,000
Portability: F
Ease of setup: P+
Ease of use: G+
Performance on the Moon: VG
Performance on comets: E
Performance on double stars: E
Performance on galaxies and nebulas: E
Performance on planets: E


Source:http://www.astronomics.com/main/category.asp/catalog_name/Astronomics/category_name/Why%20buy%20a%20reflector?/Page/1

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Why buy a refractor?

For serious lunar, planetary, globular cluster, and binary star observing – as well as for surprisingly good views of the brighter Messier, NGC, and IC catalog objects – many amateur astronomers prefer the crisp, high-contrast, diffraction-free images of a good refractor.
Under average seeing conditions, a useful rule of thumb in astronomy is that a good 3" to 4" refractor will usually outperform an average 6" to 8" reflector or Schmidt-Cassegrain for seeing details on the Moon and planets, splitting binary stars, and resolving globular clusters. The situation becomes a little more complicated when comparing refractors to Maksutov-Cassegrains or Maksutov-Newtonians, but (with a few high-priced exceptions) a good refractor will usually equal or outperform a Mak-Cass or Mak-Newt of equal or slightly larger aperture

Why? Unlike reflectors and catadioptrics (Schmidt-Cassegrains, Maksutov-Cassegrains, etc.), refractors do not have a secondary mirror obstruction or multiple-reflection optical path to introduce light-scattering diffraction and internal reflections that brighten the sky background, reduce contrast, and smear images.

Refractors also have the highest light transmission – the percentage of the light gathered by the scope that actually reaches your eye. Refractors can transmit 90% or more of the light they collect, compared with the 77% to 80% transmission of reflectors and 64% to 75% of catadioptrics. (The reflector and catadioptric percentages only concern mirror reflectivity. They do not take into account the light blocked by a reflector or catadioptric's diagonal or secondary mirror, which can reach a hefty 15% to 20% additional light loss in some scopes.)

Unlike reflectors and catadioptrics, which lose 1% to 1.5% of their reflectivity per mirror surface per year as their aluminum coatings gradually oxidize, the light transmission of a low maintenance refractor rarely deteriorates significantly with age. Century-old refractors are still used, and highly prized, by discerning amateurs, and the world's largest refractor – the Yerkes Observatory’s massive 40" – has been in constant professional use since 1897.

The result of a refractor's lower diffraction and higher light transmission? Given favorable seeing conditions, a modestly-sized refractor can show you subtle lunar and planetary features with a wider and more easily observed contrast range, and with more sharply etched detail, than is possible with the light-scattering optics of many larger reflectors and catadioptrics. This is especially true on nights of less-than-perfect seeing, when the details visible in a larger scope are often blurred by turbulence in our atmosphere. A smaller refractor looks through less of our unstable atmosphere and its images are consequently less affected by this turbulence. A good 80mm refractor, for example, can reveal more lunar detail than you can sketch in a lifetime of observing.

Diffraction spikes on a reflector's star images, caused by its diagonal mirror’s spider vanes, are absent in an unobstructed refractor. With no diffraction spikes to hide faint binary star components or smear globular clusters, refractors can resolve close-spaced stars more precisely than the typical reflector.

Since the Moon and planets are all brightly lit by the Sun, a large light-gathering capacity is not as important as high magnification within the solar system. The relatively small aperture of a refractor is therefore often an advantage for this kind of observing, as is the high magnification capability of its long focal length, as there is less glare from brightly lit planetary surfaces to wash out faint detail.

For purely visual lunar, planetary, binary and star cluster observing, an altazimuth refractor with slow motion controls may be perfectly adequate. If a family shares the telescope, however, an equatorial mount with a motor drive will keep objects centered in the field of view so all can share the same view. Close-up lunar and planetary photography requires such a mount and motor drive. Due to the limited light gathering of the smaller refractors, long exposure deep space nebula and galaxy photographs are rarely attempted with this type of telescope.

The drawbacks of a refractor? Except for very expensive apochromatic designs, all refractors suffer from chromatic aberration (or "spurious color"). This is an optical defect that produces a faint, and normally unobjectionable, pale violet halo around bright stars, the limb of the Moon, and the planets. Chromatic aberration becomes more visible as the aperture increases and the focal ratio decreases, although modern optical systems minimize the problem in two-element achromatic refractors – and virtually eliminate it in three to four lens apochromatic systems.

While they are light in weight and economical in smaller sizes, refractors become bulkier and considerably more expensive than reflectors or catadioptric scopes as apertures hit 4" (102mm) and above. A premium 4" apochromatic refractor typically costs and weighs four to eight times as much as a 4.5" reflector or 3.5" Maksutov-Cassegrain.

But these drawbacks aside, and if sheer light grasp is not essential – for hunting very faint galaxies, for example, where a larger reflector would have the light-gathering edge – the clarity, contrast, and sheer image quality of a good refractor is well worth your consideration.

REFRACTOR REPORT CARDS
(used in excellent seeing conditions and with no light pollution; adapted from Astronomy Magazine):

E = excellent; VG = very good; G = good; F = fair; P = poor.

Small aperture (2" to 3") "toy store/bargain" refractors:
Price range: $100-$200
Portability: E
Ease of setup: E
Ease of use: F
Performance on the Moon: F
Performance on comets: P
Performance on double stars: P
Performance on galaxies and nebulas: P
Performance on planets: P

Small aperture (3" to 4") achromatic refractors:
Price range: $200-$800
Portability: E
Ease of setup: G
Ease of use: G
Performance on the Moon: E
Performance on comets: F
Performance on double stars: VG
Performance on galaxies and nebulas: F
Performance on planets: VG

Medium aperture (4" to 5") apochromatic refractors:
Price range: $700-$10,000
Portability: VG
Ease of setup: E
Ease of use: VG
Performance on the Moon: E
Performance on comets: VG
Performance on double stars: VG
Performance on galaxies and nebulas: G
Performance on planets: VG

Large aperture (5" to 8") achromatic refractors:
Price range: $800-$3200
Portability: F to VG
Ease of setup: G+
Ease of use: VG
Performance on the Moon: E
Performance on comets: VG
Performance on double stars: E
Performance on galaxies and nebulas: G
Performance on planets: E

Large aperture (6" to 8") apochromatic refractors:
Price range: $5000-$27,000 and up
Portability: F
Ease of setup: F
Ease of use: VG
Performance on the Moon: E
Performance on comets: VG
Performance on double stars: E
Performance on galaxies and nebulas: G
Performance on planets: E

Source:http://www.astronomics.com/main/category.asp/catalog_name/Astronomics/category_name/Why%20buy%20a%20refractor?/Page/1

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Galileo's Telescope of Palomar

Palomar is an Italian company that has been one of the leading traditional Florentine optic companies since 1956. The current management has decided to develop its bent for design by skilfully combining past and present abilities.

On July 12th 2011 The Awards Ceremony for the XXII Compasso d’Oro has been held, for the first time, in Rome at MACRO al Testaccio, La Pelanda.
Galileo’s Telescope has been awarded with the Honorable Mention XXII Compasso d’Oro 2011.

This object produced by Palomar is collected and kept in the Historical Collection of the Compasso d’Oro Award which has been declared to be “of exceptional artistic and historical interest” and included it in Italy’s national heritage


Inspired by the telescope built by Galileo in 1609, this instrument copies the original form, focal lenght (1 meter) and construction material.

Modern optical technologies make this telescope perfect for quality astronomical observation. This versatile instrument permits observing the moon, the major planets and other celestial bodies scattered through the solar system, and is also a powerful earthbound spyglass.

A novel, original object that bridges past and present; a contemporary revisitation of timeless form and function
Design: Odoardo Fioravanti


Specifications:

•Optical glass, abs, metal
•Tube: wood or aluminium
•Objective lens: Ø 60 mm
•Focal length: 1000 mm
•Magnifications: 67x, 80x, 100x with three eyepieces as standard equipment

Price :Galileo's Telescopes have two versions. Economy vesion is made of Aluminium.
Aluminium :100 Euro.
Wood :252 Euro.

Source : http://www.europeanconsumerschoice.org/house/palomar/

http://www.palomarweb.com/web/tienda/products/view/3

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Exploring the Solar System : United States, 2000

This space souvenir sheet from the United States Postal Service features exploration of the solar system with five sun-related high face value postage stamps.

The sun images include the sun and corona, a cross-section of the sun, the sun and earth, the sun with a solar flare, and the sun and cloads. This beautiful stamp sheet was designed by Richard Sheaff and released by the USPS on July 11, 2000.

The pentagonal postage stamps in this sheet was a first for the USPS; perforation of the five stamps required special perforating dies created just for this issue.The actual size of this sheet is 185mm x 128mm (7.28" x 5.04").

In my opinion, this space souvenir sheet is one of the nice sheets of the world. Moreover, this is a popular item of primary education. At present, many students collect this for their school assignments. But they are not stamp collectors.
Source : http://www.collectiblestampsgallery.com/proddetail.asp?prod=SP37

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