Astronomy is a fascinating lifetime hobby enjoyed by young children to centenarians, by people from all walks of life and varied interests, from every corner of the earth.
You can observe the heavens on a casual or serious basis, undertake scientific study or marvel at the wonderment of our existence. Astronomy can be a fun and relaxing way to soothe our minds and bodies from our busy everyday life. It is a way to enjoy nature, being outside and marveling at the night sky.
Astronomy is easy to learn! You don’t have to be a scholar in physics or math to enjoy our universe. Besides a telescope, you will need star maps or books listing the locations of various objects, and then learn simple techniques of locating the objects. Recent developments have brought computerized telescopes to the market and they eliminate the need of sky maps and books with their built-in databases of celestial objects.
Before telling you about specific celestial objects you can see, we need to discuss what factors determine this and there are numerous factors. Most people would assume that magnification (power) is the most important factor – it is a factor but not one of the most important. Aperture (diameter of the objective lens or primary mirror) of the telescope is the single, most important factor determining what you can see. The larger the aperture, the more light it collects and the fainter the objects that can be seen are revealed, and the brighter (and better) the image will be. Greater detail and image clarity will be apparent as aperture increases.
Other factors that affect what you can see are listed here in no particular order --- optical design of the telescope, mechanical (mount and tripod) stability, optical quality, focal length, focal ratio, magnification, field of view, optical and mechanical alignment, optical coatings, magnitude of the object, quality of the accessories (eyepieces, diagonals, filters) used, seeing conditions, transparency, thermal stability of the optics, your location (urban or rural), visual acuity, observing experience, and overall manufacturing and quality levels of the specific telescope.
Some of the types of celestial objects you can view are listed below and remember that even very small telescopes – 50mm (2”) and 60mm (2.4”) sizes can show lunar details, the rings of Saturn, and other celestial wonders but with increasing aperture the observing becomes much more enjoyable.
The Moon, The Sun
THE MOON Prepare for an awesome spectacle of its rugged surface. The moon’s disk has a pastel-cream and gray background and streamers of material from impact craters stretch halfway across the lunar surface. You can observe river-like rilles winding for hundreds of miles, many rugged mountain ranges, and craters (walls, valleys, plains). At low or high power the moon is continually changing as it moves through its phases. The best viewing is when the face is only partly illuminated whereas the full Moon is actually too bright to observe fine details. Occasionally you may be treated to a lunar eclipse.
THE SUN It is safe to view the Sun if you use a proper solar filter. The Sun is fascinating to inspect as you detect and watch the ever-changing sunspot activity. With some telescope designs you can project the image of the sun onto poster board or other material safely. Some expensive type filters and specialty solar telescopes allow for very detailed observation of the Sun.
The planet in our solar
THE PLANETS IN OUR SOLAR These can be observed well from urban locations. Saturn – Many people would agree that Saturn is the most beautiful object in the sky as it is truly amazing and a sight to behold. The planet color is a pale yellow with its blue-toned polar regions. The ring structure around Saturn is amazing to see and with ever increasing aperture more details are revealed. Saturn has 18 moons and with telescopes of 100mm (4”) and larger you can see the largest one (Titan). Jupiter – You can study the cloud belts and their varying colors, the bright equatorial zone which is framed by the belts, and watch its bright moons shuttle back and forth around the planet. Watch the Great Red Spot as it changes hourly.
Mars – Observe this mysterious planet with its dust storms and orange hued deserts. The planets disk is a pale red color with its contrasting white colored polar caps which change is size during each year. You can see dark surface features. Venus – This is the brightest planet in the sky but it reveals very little detail. You can observe it going through its moon-like phases. In larger telescopes you can begin to see some dark shadows in its cloud patterns. Mercury – It is a tiny planet close to the Sun with a grayish colored disk. It is very difficult to see and the main thing to observe is the changing moon-like phases. Uranus, Neptune, Pluto – These planets are very difficult to see and there is no detail to see on these planets from amateur telescopes. You can see the greenish disk of Uranus and the turquoise disk of Neptune as well as the virtually colorless disk of Pluto with a 200mm (8”) to a 250mm (10”) telescope.
Nebulae and galaxies NEBULAE These are glowing clouds of gas and dust residing in the spiral arms of our own Milky Way Galaxy. These are typically very colorful objects but the vivid colors are only seen in CCD images or astrophotography. Using a 250mm (10”) or larger telescope in a rural location, you can begin to see some faint color on some of the nebulae and in smaller telescopes you will see very faint gray or greenish smudges. You can begin to see some faint structure with 100mm (4”) and larger telescopes. There are two main types of nebulae – (1) planetary nebulae which are relatively small ball-shaped clouds of expanding gases with faint central stars which are believed to be the remnants of stellar explosions, and (2) diffuse nebulae which are vast, irregularly-shaped clouds of gas and dust. Nebulae are also described as emission (shine brightly) or reflection (do not shine).
GALAXIES These are vast, remote “island universes”, each composed of many billions of stars. Galaxies are beyond the boundaries of our own Milky Way Galaxy and are millions of light years away. Galaxies exist in a variety of sizes with regular and irregular shapes. They are very difficult to observe due to their faintness and the distances. It is possible in a rural area to discern hints of structure on the brightest galaxies with 100mm (4”) to 150mm (6”) apertures and more structure becomes visible as the aperture increases. Galaxies are classified as (1) spiral – these feature a central bump or budge of old stars surrounded by spiral arms containing younger stars, (2) barred-spiral – these have an obvious central “bar” of material, (3) elliptical – these are armless masses of old stars, and (4) irregular – these show no symmetry, exhibiting odd or chaotic structure.
Star clusters and double stars
DOUBLE CLUSTERS Star Clusters are stars that typically shine brightly and some call glimmering diamonds or jewels of the sky. There are two types of star clusters – (1) open star clusters (also called galactic clusters) which are loosely arranged groups of stars, occasionally not too distinctive from the background stars, and (2) globular star clusters which are tightly packed groups of thousands to millions of stars. DOUBLE (BINARY) STARS These are pairs of stars orbiting around a common center of gravity, often of different and contrasting colors. Many double stars can be observed from urban locations. Some of these can reveal beautiful color, magnitude contrasts, as well as varying degrees of separation.
VARIABLE STARS These stars change in brightness over time.
ASTEROIDS
These are rocky and metallic objects of varying sizes and shapes that orbit the Sun but are too small to be considered planets. Some asteroid paths can be found on various websites and with a 150mm (6”) or larger telescope in a rural location you may be able to detect some of the larger ones. Comets – They originate from the outer reaches of our solar system. Magnificent comets are routinely visible through telescopes. They have a nucleus of a relatively solid, mostly ice and gas with some dust and a dust tail.
Non-celestial objects
NON-CELESTIAL OBJECTS
There are other objects that can be viewed through a telescope Satellites
– These are man-made objects that orbit around the earth or the Sun for
various reasons like weather, communications, military, research (space
station), etc. Websites give the locations of these objects which you
can then try to observe. Terrestrial – These are objects on the
earth. You can use most telescopes for nature and wildlife studies,
scenic views, surveillance, etc.
What you won’t see with a telescope
WHAT YOU WON’T SEE WITH A TELESCOPE You won’t be able to see the American flag on the surface of the moon or black holes. You won’t see color as you would for deep-sky objects as you would in CCD images or astrophotography because they utilize low level CCD detection technology or special films in long exposure that allow the light and color to build up on the film. Our human eyes are not sensitive enough to detect colors in faint light.
