Print This Page

What can you see?

 

The idea behind this page is to give you a feel for what objects look like through a telescope. Many factors affect what you can see through a scope, including your sky conditions and the size of scope. For more information on what you can see with what sized scope, or indeed with the naked eye, please see the FAQ page

Before you make a telescope purchase, you might like to know what you might see. Let me break the bad news to you first. You know those Hubble shots of the pillars of creation? Or the Deep Field? or that full spread poster of the Andromeda galaxy or the Sombrero? Well, forget it. No scope, used visually, will give you those images. The good news is, there is subtlety and beauty that can be seen with the eye that cannot be captured on film, so that not photo really captures the "live" experience.

Allow me to illustrate.

You have undoubtedly seen images of the Andromeda Galaxy, M31. This is our nearest large galaxy, a spiral much like our own Milky way, but about twice the size. Most of the images you have seen would look like this image, captured from Starry Night:

In the eyepiece, from a nice, dark site, it would actually look something like this:

Another popular target for astrophotography is the Ring Nebula, M57. In photos, like this capture from Starry night, it is a very colourful object:

In the eyepiece, it is an ethereal smoke ring, but shows no colour to the eye:

(for the full effect, look at the image above from about 2 m away)

Individual stars are just slightly brighter points of light, though they can be different colours. More interesting are double stars - these look like individual stars to the naked eye, but in a telescope (or even binoculars for some) reveal two stars, often with unequal brightness, and sometimes different colours, like Albireo in Cygnus. Double stars are not only aesthetically pleasing, but can also be a fun challenge. "Splitting the Double-Double", for example, is a favourite pastime among backyard observers. (the Double Double is Epsilon-Lyrae, which looks like two stars under low power, but each of those resolves into a close pair under moderate to high magnification. For more on double stars, see the Binary Stars section.

stf1424.jpg  (STF 1424 - a double star)

 Star clusters can be quite spectacular to observe. These come in two main types, known as Open and Globular. Open clusters are looser aggregates of stars, like the well known Pleiades, also known as the seven sisters. The Pleiades is a bright open cluster that is best viewed at low power and wide field - in fact binoculars are probably your best bet. Many open clusters are farther away and fainter, but still wonderful at low power in even a modest telescope.

Globular clusters are like micro-galaxies. They are spherical balls containing tens of thousands of stars. At low power, or under light-polluted skies, they look like fuzzballs - compact little puffs of smoke that are bright in the middle and fade toward the edge.  Something like this:

m13-blur.jpg

 Under clear, dark skies, and greater magnification, the fuzzball will resolve into many pinpoints of light. These are really very beautiful objects, like the Hercules Cluster (M13) below.

m13-c copy.jpg

 

One of the most truly beautiful objects in the sky is the Great Orion Nebula, M42. I won't post a picture of it here, because no picture will ever do it justice. Under dark skies, it is breathtaking. If you have reasonably dark skies, this massive cloud of gas can be seen naked eye as a "haze" around the middle of the sword of Orion. This becomes quite distinct in binoculars - even 7x35's are fine. A small telescope will give you some magnification and stability so that you can see it better, and begin to get a feel for the structure of the nebula. Under dark, rural skies aith a large aperture, you can get lost in it for hours.

 

Planets are good targets for urban and suburban observers, because they are bright enough to punch through light pollution. The trouble with planets is that there aren't very many of them. At least, not many that are readily visible to the amateur observer. Mercury is a tiny featureless disk. Venus is very bright, but featureless, except that it shows phases like the moon. Mars only comes close enough to see blotchy surface features every two years. Uranus and Neptune are small (visually), dim, and featureless. That leaves Jupiter and Saturn. These two are real gems.

Saturn is beautiful, but it almost never changes, except for the angle of the shadow on the rings as the season goes by, and the tilt of the rings from year to year. Below is an image of saturn as it would appear on a clear night of good seeing. The rings really are that bright - they are easily visible even at moderate power with a small telescope, but become quite spectacular at higher power.

saturn_ech_corrected_mar_7.jpg

 

Jupiter is more dramatic. It changes hourly - or faster, due to its rapid rotation and very active storms. Typically, two major cloud belts are visible, and under steady skies more cloud belts are visible and detail can be seen in the clouds - whorls and festoons, white spots, and of course the Great Red Spot. Also, Jupiter's four main moons orbit around the planet, occasionally passing in front and leaving a shadow spot on the cloud tops. This can be quite entrancing to see.  The moons are bright enough that they can be seen easily in binoculars, even small ones (I have seen them in 6x30 binoculars).  The image below is a good representation of what you can see on Jupiter when the seeing as average.

Was this page helpful?***00 based on 247 reviews.

0: 1: 2: 3: 4: 5:


Previous page: Observing
Next page: the Ed List