How an app can help you identify celestial objects
Apps can be an effective tool for amateur astronomers when stargazing
Though a die-hard, hands-on astronomer myself, I appreciate that many night sky observers don't own or have access to a telescope.
However, it's not really necessary, in this digital age, to have one, unless you are seriously into astronomy and enjoy searching for and observing the night sky's countless celestial wonders in greater detail.
Depending on the sort of night sky observing environment you live in, particularly if you live in an urban or suburban setting, many of the stars that might be of help to you in recognizing the constellations or locating the planets and other naked-eye objects in the night sky may not be visually available.
To overcome this problem, many night sky observers are now turning to sky apps, digital maps of the night sky, that can be downloaded onto your mobile device or home computer.
These apps range from free ones that show very basic star patterns, the location of the moon and planets to apps which must be purchased or subscribed to that are more detailed in what they show of the night sky and provide a greater amount of information about the object or part of the night sky you are observing.
The latter type of app most always allows the user to modify the view they are looking at on the screen, enabling them to change the date - even going forward and backward in time - as well as the time, observation location, depth of view and more, something which is often not included in the free apps.
Depending on the level of detail you wish to see on your computer or mobile device and the perks attached to a particular sky app, there are a number of excellent apps available. Most are userfriendly, and often quite simple to use. The mobile device apps are linked to your device's GPS program, allowing you to use the app wherever you are in the world; you simply turn it on, point it at the night sky, press an icon, and the current night sky above you is displayed on your screen, complete with constellation patterns, planets, etc.
Sky apps for your home computer, often more comprehensive and detailed in what they show of the night sky, are intended for a more in-depth view of the night sky and might require a bit of setting up and calibration, but are usually well within the computer skills level of the average person.
WHAT'S YOUR BEST BET?
As I have not personally used either computer sky apps or mobile device sky apps, I asked a friend and a fellow Charlottetown Astronomy Club member Chris Vessey, at the UPEI School of Mathematical and Computational Sciences, if he could provide me with a simplified overview of a number of sky apps that he has used and is familiar with.
Here is Chris's evaluation of three sky apps:
1) Stellarium (for Windows, Mac, Linux): Level - beginner to intermediate; Accuracy - high; Detail - high; Cost - free; a fully-equipped planetarium package; basic operations are fairly easy; can set your location's geocoordinate to see the sky at any time, future or past; has a massive database of objects; gives a huge amount of information; available, at cost, for mobile devices.
2) Starwalk/starwalk 2: both available on IOS, SW2 on Android; Level beginner; Accuracy - high; Detail - medium; Cost - US $2.99 (base information); upgrades to the database can be bought for US$0.99 each; available as adware for free.
Both these apps are great on a mobile device; simply turn your device on, select your geolocation and time; hold at arm's length, and sweep down, then up, to sync the device's accelerometer and magnetometer; will show you what you're pointing at with your arm; also gives local rise/ set times for planets and the moon, as well as lunar phase.
3) Skyview Cafe (skyviewcafe.com): Level beginner; Accuracy - high, Detail - low; Cost - free; a basic online star chart creator; generates a one-page overview of the sky, showing the brightest objects; doesn't have a lot of detail, as it is only intended as an overview, like a planisphere.
Chris's evaluation is intended simply as an overview of some of the features of available sky apps and is not intended as an endorsement of any particular app.
While these apps, especially the mobile device apps, are readily available and easy to use, they should not replace the pleasure of getting out under a dark sky, and observing the night sky with your own naked eye or through a pair of binoculars.
I view sky apps as one more tool that, hopefully, sparks an interest in the night sky for a first-time observer, and that the limited view of such apps, particularly the mobile device apps, instills a desire to learn and see more of the night sky.
THIS WEEK'S SKY
Saturn (magnitude +0.5, in Capricorn - the Sea Goat) becomes visible 10 degrees above the southeast horizon by about 11 p.m., reaching its highest point in the sky (28 degrees) above the southern horizon around 2:45 a.m., before fading with the approaching dawn around 5 a.m.
Jupiter (magnitude -2.6, in Cetus - the Sea Monster) rises in the east around 11:30 p.m., reaching 45 degrees above the southern horizon before fading from view as dawn breaks around 5:20 a.m.
Mars (magnitude +0.3, in Aries - the Ram) rises in the east-northeast around 1 a.m., and reaches a height of 43 degrees in the southeast sky before fading, along with Saturn, around 5 a.m.
Venus (magnitude -3.9, in Orion - the Hunter) is briefly visible in the eastnortheast pre-dawn sky by about 4 a.m., reaching 13 degree above the eastern horizon before succumbing to the dawn's glow by about 5:20 a.m.
Mercury, just emerging from behind the sun, is not observable.
Until next week, clear skies.
EVENTS:
Aug. 5 - First-quarter moon