Tag Archives: Images

Our Sentimental Galaxy

More than 25,000 comments have been made on Milky Way Project Talk since the project began in 2010. That’s a lot of content in itself – beyond the main classification data from the MWP’s main interface.

I’ve been using the Python-based Natural Language Toolkit (NLTK) to perform what’s called sentiment analysis on Zooniverse Talk data. Some of the most stunning results come from the Milky Way Project’s rich dataset.

The process is oddly simple – thanks mostly to NLTK’s great documentation. You train an algorithm to recognise positive and negative words and phrases in text – and then go though all the MWP subjects in Talk looking at the things people say about them, and recording whether the comments are positive or negative. If a comment is really positive (e.g. people say ‘stunning’, ‘wonderful’, ‘brilliant’) then it gets a score around 1. If it’s negative (e.g. people say ‘horrible’, ‘stupid’, ‘disgusting’) then it gets a score of 0. Of course most subjects come in somewhere in between.

So here are the results: the 20 most-positively commented on images from the MWP (click to embiggen). It’s a lovely set, and you can see why people were so positive about these images.

On the flip side, here are the 20 most-negatively commented on images. You see a mix of difficult to classify and blown-out images.

I’m now looking at ways to use this sort of sentiment analysis to extract interesting images from Talk and highlight them to moderators and science teams. It’s something I’ve been toying with on-and-off for several projects – not just the MWP. The Zooniverse Advent Calendar seems like a great time to share and see what people think of this idea.

You can find my code on GitHub along with other examples. As well as the MWP there are galleries for Galaxy Zoo and  Snapshot Serengeti.

Examples of Interesting Objects


Feedback from everyone about the Milky Way Project has been overwhelmingly positive. You all seem to love the images and the interface. One thing that is always requested though, is more tutorial examples of the things we’d like you to flag as areas of interest: green knots, dark nebulae, star clusters etc.

We decided it was best to use Talk, the Milky Way Project’s discussion/collections site, to show off examples of the objects you might spot as you draw all over the galaxy. We’ve built collections of green knots, dark nebulae, small bubbles, star clusters, galaxies and fuzzy red objects. The great thing about using Talk to do this is that we can easily add more in as we – or rather you – find them.

All the new example collections were built using the classifications you have made so far. We used your first 100,000 classifications to create lists of the objects most regularly flagged in each category. Hopefully you will find these useful in learning how to spot some of the amazing things that are out there in the Milky Way (and sometimes, beyond)!

A side effect of creating these collections was that I found the image with my green coffee this morning above along the way. It appears to contain green knots, small bubbles, dark nebulae, red fuzzies and a small star cluster. If anyone can see a galaxy in there it’s a full house! You can obviously, also discuss this image on Talk.

If you have comments or suggestions for the Milky Way Project, you can email us on team@milkywayproject.org.