The Universe on Your Phone (or Computer)

Have you ever looked up at the night sky and tried to remember the names of the stars and constellations you are seeing?  If you have a smartphone, Google has a very nice Android app for locating constellations, stars, planets, etc.  If you're an iPhone user, Apple doesn't play nice with Google, so you don't get their toys...sorry.  I included a screenshot of what Google Sky looks like running on my phone.

Your phone knows several pieces of information that allows it to generate this sky map.  First, and not at all surprisingly, it knows the time.  It also knows your location.  Even without GPS, a phone can tell where it is by what cell towers are in range.  The time and place on Earth's surface are both necessary to determine which stars are overhead.  Then, you need to know which direction in which your phone is pointing.  This is done using an accelerometer, which can measure which way gravity is pulling on the phone.  With all that, you can point your phone up and - voila - the stars and constellations on the screen follow the ones in the sky...except these ones are conveniently labeled.  Another neat feature of Google sky is that you don't have to pan around the entire map to find a particular object.  Being a Google product, this also includes a search function.  I showed a screenshot of locating Mars.  The circle is red to indicate that I'm almost pointing directly at it, and it would be blue far away.  Google Sky also has a website here, which also includes visible, infrared, and microwave observations stitched together into a full-sky map.

While it is not as accessible as Google's products (it's a program that only runs on Windows 7/8 computers), Microsoft Research's WorldWide Telescope offers access to a much larger amount of data.  This includes planetary data, and the ability to browse in 3D.  If you click here, you can see a sample dataset they put online allowing you to look around the MilkyWay in 3D (click your mouse and drag on the picture...it's not just an animation).

The great thing about both Google Sky and WorldWide Telescope is that they are both intended to be used by the general public.  They were designed by consumer companies (Google and Microsoft) with that use in mind.  This has two big advantages:  First, the webpages and documentation were written assuming a home user would be reading them.  Second, the user interfaces were designed professionally, eliminating a great deal of confusion in the first place.  Happy...observing?