Go Out:  Look Up!

A Guide to the Sky, Telescopes, and Telescope Programs

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Target Types

What Type of things are there in the sky?

Here are some additional links for urban observers: Urban Skies

(photos are somewhat representative of views through a small scope in medium skies)

The Variables:


Great Target even in very bright skies. Very bright, you will want to use a Moon filter when it's anything thicker than a crescent or a quarter (it will destroy your night vision). 

When the moon is at a phase other than Full (or near full), the shadows at the terminator make it easy to see detail in the terrain: craters, mountains, valleys.  At Full Moon, shadows are not visible and the terrain looks very two-dimensional.

When looking for Deep Sky Objects, avoid bright moonlit nights.


Jupiter and Saturn are Great Targets even in very bright skies.  Jupiter's bands and its four largest moons are almost always visible, even in a small scope.  Saturn's rings are stunning, even in a small scope, and its large moon Titan is easily seen.

Mars is bright but it lacks readily-resolvable features in a small scope.  When it's close to the earth (every 26 months) dark grey surface details can be seen on  its orange/salmon-colored disc and a polar ice cap can be seen - but only through large scopes.

Venus will show a phase (like the moon) but no details; it is always near the Sun (a dawn or dusk "star").  Mercury is like Venus but harder to observe (smaller and much closer to the Sun).

Uranus will show a blue featureless disc in larger scopes, but is hard to find.

Neptune looks like a faint star even in the largest scopes.


Since the  Moon and Planets move around, they pass each other and bright stars.  These events are generally best viewed with the naked eye or binoculars.  Occasionally a conjunction will be tight enough to view through the narrow view of a telescope.

Jupiter's and Saturn's Moons

Jupiter's and Saturn's large moons are visible in telescopes and vary in position from night to night and sometimes from hour to hour (Io in particular has a very short orbit around Jupiter).  Sometimes the moons transit the planet, are eclipsed by it or cast its shadow across it.  These events are predictable and times are available on the internet.  The blurb below is from an event that occurred during Curie Elementary's Annual Stargazing Night, Feb 3

In addition to the "generic" winter sky highlights, an interesting event will be taking place while the scopes will be gazing skywards:  Jupiter's moon Europa will be transiting Jupiter's disc and at 7:30 Europa's shadow will start to creep across Jupiter's disc.  Generally, both Europa and its shadow should be visible.  The major variable here is how close to the horizon Jupiter will be at 7:30 pm.  The shadow will more than likely be visible; Europa itself might be hard for little eyes to pick out.

Here's a picture and a simulation:

click for larger picture

click here for a Quicktime Movie

The Sun

First, never look at the sun without an appropriate filter in place.  Instant and permanent eye damage can occur.

The sun is a great observing target, if you have appropriate equipment. 

Observing the sun can be done from anywhere: urban light pollution and dirty urban air have little on what you can see.

While you're only looking at one celestial object, the sun's activity changes from day to day. 

Sunspots vary in number and size.

Hydrogen-alpha viewing (show to the right) also allows viewing of other solar features, such as Prominences, Flares, Sunspots, Active Regions and Filaments.

The sun rotates once every 25 days or so.  Over the course of a week you can see the features move across the disk.

Click here for more info on Solar Observing.

The Deep Space Constants

I'll discuss in rough order of what is good from a bright urban sky with a small scope.


Single, normal stars are generally not more interesting through a telescope than with the naked eye.  Stars are so far away that even the largest telescopes fail to resolve them as anything other than a pinpoint of light (no discs are visible).

Multiple Stars

Most stars are part of a multiple-star system.  There are many multiple star systems that are visible even from bright skies.  Many observers love to "split" double stars, seeing if there equipment and their eye can discern two stars that are very close together or of very different brightnesses. 

In addition to true multiple star systems, some unrelated stars appear close together because they're in the same direction relative to earth; these are called "optical binaries".

Variable Stars

Some stars vary in brightness, some enough to notice over a predictable period of time.  Familiarity with the sky is critical to appreciate the variation.

Open Star Clusters

Star Clusters also suffer relatively little from a bright sky.  Some are quite visible with the naked eye.  Binoculars and small scopes are excellent to see dimmer members of the cluster.
The famous Double-Cluster.

Globular Clusters

Globular Star Clusters are some of the most impressive of Deep Sky Objects visible from light-polluted skies.  Globular Cluster are tight balls of up to a million stars that are scattered outside the disk of our galaxy.  They are visible in binoculars and small scopes.   Larger scopes allow you to resolve the core into individual stars.
The Great Hercules Globular Cluster.

The Milky Way

Easily visible by naked eye in a moderately dark site (out of the suburbs), the Milky Way is often mistaken as a band of clouds.  In a way it is: a permanent massive cloud of stars and gas.  We are smack in the middle of the disk of our galaxy and the Milky Way surrounds us in a loop that circles the sky.  From a dark site, sweeping through the Milky Way with binoculars or a telescope is awe-inspiring, full of all sorts of deep sky goodies.


Galaxies are largest and most intellectually-impressive objects to be seen in the sky.  Visually, however, they are dusty smudges, except for a handful when seen from dark skies.  Knowing that the smudge you are looking at contains 100 billion suns is pretty awe-inspiring, though.    The Andromeda Galaxy can be see with the naked eye from a dark sight and is visible with binoculars and a small scope from bright skies.  Other galaxies are visible from suburban, skies, but the darker the sky, the better the view.  M81 and M82 are favorite urban targets, as one is face-on (round smudge) and the other is edge-on (cigar-shaped).  They are both visible in the same view.
Leo Triplets M81 and M82


We've all see those majestic Hubble shots of "The Pillars of Creation" and other nebulas.  Looking at nebula through a small telescope from urban skies is decidedly less majestic.  Nebulas tend to be low brightness, low contrast grey objects.  They do not have the photon energy to fire off our retina's color receptors.  They look like small static clouds ("Nebula" is Latin for cloud).  There are some exceptions to the "Not overly impressive" rule, though, namely the Orion Nebula.  It's found as the middle "star" in the sword under Orion's easily-found belt.  Dark skies and big scopes bring out more nebulas and their details.

Planetary Nebulas

Planetary Nebulas are stars blowing off their atmospheres.  There are a number that are visible from urban skies.

Google "Messier Objects" for this list of 109 cool deep sky objects.


Questions or comments? Email:Jeff Martin