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This chapter introduces some of the general guidelines for starting an observing program for faint objects. The objects featured in this book are mostly those that need a telescope with an aperture of 10 in. (25.4 cm) or more, observing in relatively dark to very dark skies. One may also use these techniques to observe somewhat brighter objects from light-polluted locations or with smaller instruments. What is common for both setups is that one is looking for something that lies at or near the edge of visibility and that person is trying to get the most out of the observation.

Galaxies are huge collections of stars and vast amounts of gas and dust and are found throughout the known universe. Galaxies outside our own are so far away that the stars blend together into an amorphous haze, and some of the dust (in larger concentrations) is visible in silhouette against the bright material (e.g., the dust lane of the Andromeda and Sombrero galaxies). They come in various morphologies and are categorized into four groups based on their appearance in the sky: ellipticals, spirals, barred spirals, and irregulars. They can contain as few as tens of millions of stars but as many as hundreds of trillions of stars.

Let’s take a look at some of the “starships” of our time, facilities that have given us the deepest views of the universe ever seen by humankind. The “starships” referred to here are the largest ground-based telescopes, the Hubble Space Telescope, and the other three members of NASA’s “Great Observatories” (Spitzer Infrared Space Telescope, Chandra X-ray Observatory, Compton Gamma Ray Observatory), all of which have given us our deepest views of the universe yet. They are called “starships” because of their ability to “take” us to these distant places through extreme imaging, either looking out in wavelengths invisible to the human eye or collecting sparse amounts of photons over (for example) a 30-h period to reveal the most distant galaxies that would otherwise be invisible.

Astronomy is the oldest of the physical sciences and can be traced back to antiquity or at least 5,000 years ago [1]. Looking that far back in time, we see the origins of astronomy mixed in with the religious and astrological practices of pre-history. Ancient societies were already able to tell the wandering planets from the “fixed stars” and associated these moving objects with gods and spirits. Various cultures have practiced various religions related to astronomy, with the priests playing the role of the “professional astronomer” of their time, and demonstrating a “divine” understanding of the movements of the heavens. So it seems that the first few millennia of astronomical involvement of human societies were religious in nature.

The next few chapters provide a basic “Astronomy 101” introduction to the types of objects that will be looked at later in this book (and you will look at later through your telescope). We are focusing on faint objects outside the local Solar System; information about faint planets, comets, and asteroids can be found in books written about these classes of objects. Our focus is on objects that can be found throughout interstellar space, along with objects found beyond our very own galaxy to the edge of the known and visible universe. But first here are some basics on the main kinds of deep sky objects that we know of.

This chapter presents a catalog of documented events on the Moon likely (or possibly) resembling impact phenomena. These events are referred to by the author as possible impact phenomena (PIPs).The catalog was assembled from several different sources, listed later, and is divided into sections by century, beginning with the twelfth century. Naturally as one approaches the present day, the number of reported events seems to rise exponentially as the number of observers, as well as the efficiency of the methods of observations, increases. For example, in the entire seventeenth century, two events were recorded compared with 19 during the 1950s.