I Made An App.


I released my first app.  Check it out.

It’s an astronomy quick reference, called  “My Messier”,  for iPhone and Apple Watch.

When Apple Watch was announced, I thought I’d write an app for it (as an excuse for getting one.)   With a new mobile device, people would want new apps for it. I needed to make an iPhone app too because the iPhone launches the watch app.  I wanted to make something simple but useful.  I love astronomy so it would be great if the app were useful to me as well as others with the hobby.

When I’m showing people something in my telescope, they often ask how far away it is. Likewise, when I’m around others with telescopes, and they say they’re looking at a particular object,  I sometimes don’t even know what kind of object it is, much less how far away.  A lot of the time we are out in the country to get away from city lights, and have no internet connection to look it up.

Astronomers refer to objects by numbers a lot.  For example, NGC 891, 3C 273, or M72.   The things starting with an “M” are Messier objects, named after the 18th century French astronomer Charles Messier.  He was looking for comets, and when he came across something that might be mistaken for one, he would make a note of it so he and others could eliminate it from their search.  The list with these objects, the Messier catalog, ended up with 110 objects:  mostly galaxies, nebulae, and star clusters.  The constellation Orion (the photo I took above) contains M42, the Orion Nebula.   I decided to make an app that would list Messier objects, giving some basic data and a photo for each one.  There are other apps that have the Messier catalog, but none of them presented the objects quite the way I wanted, and none of them had the catalog on a watch.

It was a lot of work to add the 110 objects, gathering and presenting the data, collecting and editing the images and putting them together both for the phone and watch.  I made a spreadsheet with all the information and it kept growing and growing, with more and more columns.  I had to update, correct, and recheck the data over and over, always finding little errors, and I had to make separate, reformatted versions of some data for the small watch screen.


Programming took some effort too. I had been making a game for the iPhone using Objective-C language and Apple’s Xcode tools, but the Messier app was my first project with the Swift programming language.  Finally I stopped adding features, tested it (thanks to my tester friends), polished it, went through the Apple approval and distribution process, and released it.  So now people around the world can download and use my app on an iPhone and Apple Watch and see lots of cool pictures and facts of space stuff.

Some night at an astronomy club gathering  I might ask someone with a telescope, “what are you looking at?”  and they might say, “M106.”   I tap  the screen on my wrist, see it is a spiral galaxy in the constellation Canes Venatici, and that is 23.7 million light years away.  I might look in the eyepiece and say, “oh, that one has a water vapor megamaser.”  But probably I won’t be a showoff and I’ll just say, “wow.”  Then they’ll look at their wrist and say, “yeah, it’s 23.7 million light years away.”


See My Messier app in the App Store.

See My Messier app on my apps page.

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