New Feature: Deep Linking

Yesterday I did a bit of coding and added a new feature to Sunsetter: deep linking. When you make a query to find a sunrise or sunset forecast, the address bar will update with a link you can copy and share or send to friends to show the same page you were on.

For example, here’s a link to the alignment between the Tokyo Skytree and Fujisan:,139.810744&poi=35.363976,138.732217


Early November or February should make for some nice pictures!

Feel free to share some nice alignments with your friends.

Predicting Manhattanhenge

There has been a lot of talk lately about the Manhattanhenge, the 2 days in the year when the sun sets in the alignment of New York streets (thank you city grid design).

Manhattanhenge By @NYCphotos-flickr

It’s awesome to see so many pictures like this popping up on flickr and instagram because this way I also get to confirm my little app Sunsetter is actually giving correct results:

Manhattanhenge prediction on Sunsetter

Note: the app is configured to predict when the sun’s lower limb touches the horizon, not the civil sunset when the sun completely disappears behind the horizon, as this makes for a better picture.

Tokyo is not an easy city to take such pictures but so many cities in the US have the potential. For example, I’m hoping to see many pics from San Francisco on September 24th.


Pet Project: Sunsetter

At home I have a nice view of the Fujisan to the south-west. I often take pictures of it in winter when the skies are so clear.

Many times I’ve told myself it would be nice to take a picture with the sun setting right behind the mountain. I’ve searched the internet for an app that would tell me when this happens but all I could find were apps that tell you where the sun sets on a particular day, not the other way around. So I decided to build it…

Sunsetter is a simple python web app running on Heroku. It’s based on the brilliant pysolar library for the hardcore astronomical calculations and binds it all to Google Maps with a dash of Ajax and JavaScript.

The app still needs polish but the data it gives out should be pretty accurate and reliable at normal altitudes (standing on top of a very tall mountain overlooking a wide plain will change the distance of the horizon and screw with the calculations a bit).

If this app was useful to you or you have suggestions, I’d love to hear from you in the comments.

Update (2012-06-03): I’ve open sourced the code on Github.