So, What is There to Look At?
This is the reason for the hobby. There is so much to look at out there it’s truly staggering. Some amateur astronomers choose to focus their efforts almost exclusively on one type of object to look at in the sky: such as only the planets, or comets, or nebulae, or variable stars (stars that appear to change in brightness on a cycle) or even galaxy clusters!
The few examples I’ve included on this page are just a small sampling of what you can see on any given night. But there are several things that the newcomer to amateur astronomy must remember about viewing objects in the sky: not everything is visible all of the time. However, all things in the sky are on a predictable cycle and you can find out when to find what you want to look at what we see through a telescope eyepiece in the field is almost never what we see in the pictures on this Website, in books, and in the media those colorful pictures are obtained either by long-term (as in hours!) exposure and/or image enhancement to highlight the features of the object our eyes simply can not collect enough light to see the amazing colors in those pictures it takes practice to learn how to pick out finer details in many objects good examples of this are Jupiter and Mars: they look quite fuzzy at first, but over time, when you learn what to expect and what to look for, you can begin to pick out more detail.
Our Solar System
Below I’ve included the most interesting objects in our own solar system to view through either binoculars or a telescope. I didn’t include Mercury, Uranus, Neptune, or Pluto because, to amateur telescopes, they are so far away that at best they just appear as colored dots slightly larger than stars. Even on Venus, while obviously a disk when viewed in a telescope, there are no features visible. Each picture is a link to the Astronomy Picture of the Day (APOD) site where there is a wealth of information about each of these planets (and the Sun).
With proper filtering, the Sun looks black and white – well, light gray and Sun spots are black. It’s fascinating to watch the progression of Sun spots across the face of the Sun. You can find out when they will be transiting the Sun’s surface at NASA’s Solar and Heliospheric Observatory (SOHO) site. Remember, never, ever look at the Sun directly or point any optical equipment at the Sun without proper protective filtering! That black dot in the picture is actually Venus!
We are all familiar with the Moon, of course, but when seen through binoculars or a telescope, the detail that can be seen is truly amazing. You can see long stretches of mountain ranges, and “bumps” in the surface from volcanoes, and, of course, the craters that cover the entire surface of the moon. These are just a few of the many things to look at at our most familiar and closest neighbor in the sky.
The picture to the left is a great example of what we see when we look at Venus, either through binoculars or a telescope. As I said above, you can’t see any features, but it’s interesting to look at 1) because it’s very easy to find – the third brightest object in our sky after the Sun and Moon, and 2) because it actually has phases like the Moon, as you can see in the picture.
This picture of Mars is a little better than what most amateur astronomers will see with their telescopes. You can see brown, and shades of dark red areas, plus some gray at the poles. There is a little less definition between the different region’s colors, but the interesting thing to watch on Mars is following its rotation and watching the different features on the surface of the planet.
Jupiter is a favorite to go back to time and time again. Every successive viewing reveals more details that you didn’t see before. The black circle in the picture here is actually Europa’s shadow. There are four moons (called the Galilean moons because the Italian astronomer Galileo Galeli discovered them in 1610) that are easily seen with binoculars: Io, Europa, Ganymede and Callisto. It’s interesting to watch as they orbit the gas giant. In an evening you can see them change position quite a bit.
Saturn is another favorite simply due to the “alien” appearance of the planet with its rings. There is one moon, Titan that can be followed around Saturn – the other sixty-two moons are too small for amateur telescopes to find.
Deep Space Objects
Deep space objects (DSOs) are for most amateur astronomers the meat and potatoes of astronomy. Nebulae (emission and planetary), galaxies (edge-on and face-on), clusters of stars (open and globular)… There is so much to see.
A reminder of what I said above about the images: the incredible and beautiful pictures you see here and elsewhere of DSOs are from professional telescopes such as the Hubble telescope or amateurs that put their digital camera in front of their telescope’s eyepiece for hours at a time, or they literally took hundreds to even a thousand pictures and stacked them on of one another with special software to get the final image. Our eyes just can’t collect enough light at one time to resolve color in anything below a certain brightness. We can see the color of stars, but that’s where the color ends outside of a picture.
This is probably the single-most discouraging thing about amateur astronomy to newcomers: they see the multi-colored picture of a nebula and believe they will be able to see that in their telescope. It just won’t happen.
This isn’t to say that what can be seen in a telescope’s eyepiece is boring, what we must keep in mind when we look at these things are that they are hundreds to thousands (in the case of galaxies, millions) of light years away. That in itself is amazing!
Constellations are to the night sky what countries are to a map of the world. They define a specific area that we can observe. The International Astronomical Union has defined 88 constellations to divide up the sky. This makes it easier to identify where in the sky an object is. The constellation Orion, pictured here, is where you would start if you wanted to find the Orion Nebula.
“Asterism”? What the heck is an asterism? It’s a funny name for some very well known groups of stars. The picture to the left here reveals that the Big Dipper (the upper left grouping of stars) is actually part of a larger group of stars, which make up the constellation Ursa Major (The Great Bear). An asterism is simply a named grouping of stars in a pattern that is not (but is usually part of) one of the 88 constellations.
When a star is “dying”, it emits gasses (mostly oxygen and hydrogen) that emanate out from the star. The result is a beautiful pattern surrounding it. Pictured here is the Dumbell Nebula, so named for the hourglass-like pattern of gases.
The birthplace of stars. The constellation Orion is home to perhaps the most famous of nebulae, the Horsehead Nebula, part of which is pictured on this guide’s home page. To the left is the Eagle Nebula. As in planetary nebulae, emission nebulae consist of gasses, only they also contain dust particles. These dust particles collect along with the surrounding gases and eventually form stars.
Another funny name (sometimes called “globs” for short), globular clusters consist of tens of thousands to even millions of stars! This particular cluster is the Hercules Globular Cluster. It is 20,000 light years away, about 150 light years across, and is home to more than 100,000 stars.
An open cluster, as you may have guessed, is simply a group of stars loosely bunched in a local area of the sky. The image to the left is one of the more well-known clusters: The Pleiades, also known as The Seven Sisters.
In very dark skies, this galaxy, the Whirlpool Galaxy, can be seen with the naked eye, although not so well-defined as in this picture. Another familiar galaxy – and the one closest to our own Milky Way Galaxy is the Andromeda Galaxy. There are many, many galaxies to find in the sky, including large clusters of them!
Comet Hale-Bopp peaked in brightness in 1997 giving quite a show that many had never seen. Of course, there is the famous Haley’s comet, but there are many more to be found that come around more often than every 76 years. Note the Pleiades in the lower-right corner of the picture. Also, the “V” pattern of stars on the left is the head and horns of the constellation Taurus.
Asteroids are a challenge for most amateur astronomers, as a larger telescope is generally required to find these small, faint objects. This particular asteroid is named Ida and is approximately 36 miles long and 14 miles wide. The amazing thing about this particular asteroid, however, is the fact that it has its own moon! It is the small dot on the right of the picture. The moon, Dactyl, is only 1 mile in diameter.