Second community App experiment!

It's high time for another community experiment using the Loss of the Night app!

Last year we examined how stars come out during twilight, which is also useful for understanding the different times at which stars come out for people. This time, we're going to try seeing how much variation there is in an individual observation due to the random set of stars selected by the app.

To take part, you should make an app observation with 8 stars (quit once you've reached 8 stars). Then, start the app again, and do a second 8 star observation. To make sure that we don't see changes due to city lights going off, both observations should be completed within a single 30 minute period.

Both times you run the app it will probably start with the same first and second stars, but the rest of the stars are likely to be different. Since you are the same observer looking at the same sky, your data will help us understand how much of the variation in observations is due to the design of the app itself, rather than differences in sky brightness.

You can do this on as many evenings as you want to from September 22 until about October 6. I'll present the results in an app newsletter email and here on the blog towards the end of year.