A screenshot from the Star Walk iPhone app -- a graphical sky provides a guide for the direction you are looking. vitotechnology.com
The widespread availability of smart devices -- like my Apple iPhone -- has opened a whole new window into the Universe, making it more accessible than ever before.
Using internal compasses, accelerometers and GPS locators our handheld devices know where they are and what direction they are pointing in without the owner having to lift a finger. This revolution in mobile technology has made it so much easier for amateur astronomers to find our way around the night sky.
Of all the applications on the market, a few stand out for me and are ones I use regularly in my work. Here's my top five (paid) iPhone astronomy apps in reverse order:
5. Solar Walk: It's not an application that has any great practical value for astronomers, but from the point of view of educating and inspiring, it does a lot. To be able to fly around the solar system and zoom in or out of planetary systems with glorious high quality graphics, even in 3D (3D glasses not included), has captivated many children and adults alike. Price: $0.99
4. GoSatWatch: As the name suggests, this app is all about watching satellites. It shows a real sky view from where you are of the satellites visible at that moment, including the International Space Station. The view can be switched from 'sky view' to '3D Earth view' as if looking down from space. You can even get a list of all satellite passes now and in the near future. It's all highly configurable, including a night vision mode that switches colors to varying shades of red so not to disturb your eyes' dark adaption. Price: $9.99
3. Astro View: This is a great little calculator for the active amateur astronomer. By entering details of your telescope and eyepieces, you can switch between them to see what the field of view will look like with many other values such as magnification, limiting visual magnitude etc. It's also got the requisite night vision mode too. It takes a few minutes to gather your data and set it up but a must for the observer. Price: $1.99
2. Solar Monitor: This app is essential if you are a fan of the sun and auroral displays. It looks pretty complicated when you fire it up and it does require a connection to the web to get the latest data. The most recent images from NASA's Solar Dynamics Observatory (SDO) are visible along with some very comprehensive details about the activity on the sun and its impact on the Solar System. One of the most popular aspects of this application is that it tells you the Kp index, which is a number attributed to the level of disturbance in the Earth's magnetic field. A higher number means more disturbance, meaning a higher chance of aurora. Price: $9.99
1. Star Walk: In 1st place is an application that shines in this crowded app market place. The capability of modern phones and tablets to determine location and direction they are pointing makes them ideal for guiding people around the sky. The addition of an easy to use graphical interface, which is highly configurable, makes this app my favorite and one I use most often. By simply holding your phone up to the sky, it will show you what celestial wonders can be seen. There are many applications like this one but I find this one the easiest to use and the one that has the ability to configure where it's needed. It has the usual night vision mode and, for a quick and simple 'point to view the sky,' this is my application of choice. Price: $2.99