The Shallow Sky - Domain of the Amateur

Jack Kramer

Few things are comparable to looking through a telescope at another galaxy millions of light years away. It's easy to understand why professional astronomers become so involved in the big questions of cosmology, to the exclusion of other topics. This has resulted in a movement away from studies of the solar system by the professional community. The solar system is sometimes referred to as the "shallow sky", as distinct from the deep sky of galaxies, star clusters, and nebulae.

A quote from the late Gene Shoemaker characterizes the situation. "Astronomers have essentially abandoned the solar system. In the nineteenth century the solar system was the object of central interest in astronomy. As their tools improved, astronomers focused their attention on what they called the larger questions. That's what the Hale telescope was built for -- to put enough horsepower in the optics to go after the structure of the universe." Richard Preston, a science writer, quotes one Caltech astronomer saying, "Planets are the slag heaps of the universe...The only thing the earth is good for is to serve as a platform for a telescope. But we are going to have to get rid of this atmosphere. Then maybe we will see something interesting." To this, Shoemaker responded, "The solar system is an insignificant bunch of dust. It also happens to be where we live."

As a result of the focus on cosmology, those few professionals who remain in solar system astronomy often turn to the amateur community for assistance. Some of our number have achieved prominence for their contributions. Obvious examples are David Levy for his work with comets and Don Parker for his planetary imaging. Both Levy and Parker have worked on their own and at observatories right along with professionals.

Amateurs are fortunate. We have the freedom to observe what and when we choose. As such, we are not bound by previous project commitments nor do we have to vie for precious time on an observatory telescope. (Obviously, we do face other limitations, such as family and job commitments.) Moreover, the capabilities of instruments now available to amateurs have provided the means to do what is often referred-to as "serious" work. The other side of the equation is that the size and brightness of many solar system objects puts their details well within the grasp of amateur observers.

But there's a stumbling block for many amateurs. In order for observations to be useful, over and above a commitment to observe, you must also commit to specific, scientifically-valid observing methods and recording procedures. Having investigated some of these projects, I found this goes well beyond the casual backyard observing to which most of us are accustomed. But there's an organization that can help. This is the Association of Lunar and Planetary Observers (ALPO). It's an organization of over 500 members, both professionals and amateurs. Not only do they serve as the focal point for collecting reports from amateurs, but they also provide information and guidance on specific projects. By the way, in addition to celebrating the 50th anniversary of the Astronomical League in 1997, that year was also the 50th anniversary of ALPO.

One example of amateur-professional cooperation involves the observation of Mars. The International MarsWatch is a group founded by amateur and professional astronomers more than 30 years ago to facilitate better communication between the amateur and professional Mars observing communities. The primary purpose of this project is frequent CCD imaging of Mars using Blue, Violet, Red or other standard filters and visual drawings and photos in order to monitor the planet's atmospheric dust and cloud activity. This year's apparition is particularly important because the U.S. Orbiter (Mars Global Surveyor) will start regular imaging during this time. The orbiter will be in a low sun-synchronous polar orbit, so it will only see the surface of Mars around 2 a.m. and 2 p.m. local time (the rest of the planet will be over the horizon). Therefore, high quality ground-based observations are needed in order to place these single-time-of-day orbiter views of the planet, as well as the single-location lander data, into a global context. Up-to-date information is available on the MarsWatch page of the Astronomical League web site. The URL is:

Here you will find images of Mars contributed by amateurs and professionals, tools to aid you in planning your own Mars observations, current and past issues of the International Mars Watch Electronic Newsletter, and links to other Mars-relevant sites on the Internet.

If ever you had a desire to do real science, the solar system offers that opportunity. ALPO welcomes observing reports from everyone, members and non-members alike. The ALPO web site is:

If you decide to join, their snail mail address is c/o Harry D. Jamieson, P.O. Box 171302, Memphis, TN 38187-1302, or e-mail to Membership costs $23.00 per year and includes the quarterly journal, The Strolling Astronomer. Members also qualify to participate in the ALPO semi-formal training program. First, decide where your interest lies. ALPO is divided into several sections, depending on the field of study: solar, lunar, Mercury, Venus, Mars, minor planets, Jupiter, Saturn, remote planets, comets, meteors, instruments, computing, and Mercury/Venus transits.

Although ALPO is the best known organization for amateur and professional cooperation in solar system work, there are other groups interested in this area. For example, NASA will sometimes put out a call for observations by amateurs in conjunction with space missions. The Planetary Society, on the other hand, is more of an advocacy group, rather than being oriented toward observation.

Of course, you don't have to join an organization to observe the solar system. Do it for the pure pleasure and satisfaction that it brings. Perhaps the most persuasive reason to do solar system work is that, for the most part, these objects are unaffected by light pollution. Most galaxies may be unobservable from your home due to the glare that fills our local sky, but the moon or a planet shining up there invites exploration. The solar system lies just in our backyard, so to speak.