Virtually clear skies — anytime!
Unlike the scholarly and scientific articles that normally appear in this space, my occasional contributions will focus more on the novice astronomer like myself. As a member of the Adirondack Public Observatory, I often assist with stargazing events. I will try to address some of the common and basic questions I hear regarding the night sky. This is my wheelhouse right now, and I think I can capture the perspective as a fellow neophyte.
As a beginner to astronomy, and not remembering much from my high school astronomy class many years ago, my intent is to learn as much about the night sky as my brain can hold. This requires consistent practice and dedication. Of course, memorization made me balk in high school. But ironically, it is just what is called for now, and probably was back then.
For me, there is no better feeling than heading out on a clear night for stargazing. A portion of that time is always dedicated to memorization. Looking up at the sky, I identify what I can, close my eyes to see it again in my mind, and finally name it. Adding new objects each time has given me a small list of things I can find easily. But remember, I said it requires consistent practice.
This winter has been particularly frustrating. Since December 1st, over half of the night skies have been blocked by rain, snow, and cloud cover. Odds were that on a night that I could get out to expand my map, there was no sky to see. I could feel my small map slipping away. Then I found a work-around.
There is no shortage of apps for cell phones, tablets, and desktop computers dedicated to rendering the night sky in real time. Each of them has a base set of features that are similar in purpose, but function in slightly different ways. I have become a connoisseur of these apps to overcome my frustration with this winter’s visibility. From my living room couch, office computer, or even during a sleepless night in bed, these apps provide a detailed view of celestial objects from any angle at any time in the past or future. I’ll attempt to highlight some of the most common features and how they can be used.
At the most basic level, the app needs to know where you are and what time it is. By using GPS information from your device, the app can automatically locate your position on the planet and what time it is. This gives you an accurate picture of the sky at that location and time. For example, if you are facing north in northern New York, more of the sky below Polaris will be visible than if you are in Florida, where the Earth will block some of that view. As time passes, the Earth’s rotation causes some objects to rise and set. If left alone, those objects will appear or disappear from the app’s screen in real time just as they do above.
The touchscreen can be used to slide the sky in any direction. Touch and drag, and the sky will move with your finger. The inverse allows the compass feature to take over. As you point your device toward the sky, the screen follows the motion to display that part of the sky. You can zoom in or out to narrow or widen the field of view. Some apps contain a “deep sky” feature that allows you to zoom in and reveal great detail. Often, real images take the place of simulated views of these objects. Additional information can be revealed about an object by touching the screen again.
The time feature allows you to “time travel.” The forward and fast-forward feature advances time by the touch of the screen. Rewind and fast-rewind work the same way. Options to adjust the interval of time by seconds, minutes, hours, days, months, and even years can help plan for stargazing years from now. My favorite activity is to center Polaris, set fast-forward for a one-year interval, and watch Polaris slowly drift away from the North Celestial Pole, the point on the sky Earth’s axis points toward.
In most cases, the display is entirely customizable. You have the ability to show (or not show) constellations and/or asterisms as lines or as figures, reference lines and grids, and essential reference points such as Zenith and Nadir. Additionally, a slider allows customization of the magnitude of the visible stars so you can match the app with the density of stars in the sky at that time.
Some of the more advanced features become important as experience grows. One of those features is a synchronized account in an app where different devices are used. For example, as I sit at my desktop computer and plan an evening of stargazing, it is handy to create a list of objects of interest at a specific time, date, and location. These lists can then be synced with a smart device and taken into the field later for easy access. When in the field, a simple touch of the screen brings those objects into view on the device, and points you in the right direction.
Another feature for the advanced user is the ability to control a telescope and mount from within the app. Bluetooth- or WIFI- enabled mounts are required for this feature, usually resulting in additional cost. The benefit is that the smart device replaces the hand controller, and works seamlessly with the GoTo function by using the device’s touch screen.
It is important to emphasize that the features I mentioned above are not available on all of the apps. A quick Internet search will result in numerous apps with various functions. A few of my favorites are (in no particular order): SkySafari Pro, Stellarium, SkyView, Sky Guide, SkyPortal, Sky Tracker, and Starmap. Most of these apps have free or lite versions. Having said that, it never breaks the bank to upgrade to the full version, and often the benefit is substantial. All of them will allow you to enjoy a virtual clear sky regardless of the weather conditions.
As a learner, it is a great option, and my learning has continued throughout this cloudy winter. When I assist with Friday night stargazing at the Adirondack Public Observatory in Tupper Lake, the number of visitors who are unaware of this option has surprised me. As an educator, it is an invaluable tool to help learn the night sky. But, from a purist standpoint, I can’t say that Galileo would approve.
Volunteer novice astronomers like myself and more seasoned observers of the Adirondack Public Observatory invite you to enjoy viewing the wonders of the cosmos and share our knowledge of astronomy apps at our Roll Off Roof Observatory (RORO) that is open to the public on the first and third Fridays of each month approximately one half-hour after sunset. Please come and view through our telescopes and learn about the Wilderness Above.
For updates and notices, check out our website at adirondackpublicobservatory.org and our Facebook page. On our public observing days you can also call the RORO at 518-359-6317 to talk with one of our astronomers.