It’s here! A brand new citizen science project! Everyone, welcome Mercury Mappers to our happy family.

Technically, it is still in “beta” which means that all the site content isn’t in place, but we are so excited to have the data and tools up and running that we’re going ahead and sharing it anyway. This project lets you get a close-up look at the Solar System’s innermost planet through the “eyes” of spacecraft MESSENGER which has been in orbit since March 2011 and is now in its extended mission.

If you’ve been using MoonMappers or VestaMappers on our site already, then you are quite familiar with marking craters. If not, it’s pretty simple and I’ve recently posted a short video tutorial on what to look for.

However, Mercury is a different world from either the Moon or Vesta, so there are some different features that you want to pay attention to. First, there are lots and lots of crater chains on Mercury, so we have a special button to mark for that. No need to specify location; just click the box when you see a line of craters like in this example.

UPDATE (7 Dec): I totally borked the following explanation. There will no longer be a bullseye crater option because those won’t be showing up at these size scales! However, there are some really fun and interesting complex craters to explore, but mark them as usual with the circle, not the “Mark Feature” button.

I also noticed quite a few “bullseye” or concentric craters. These are craters that have an “inner” rim as well as an outer rim, as if material has fallen in down the wall. Go ahead and use the “Mark Feature” tool to pin those after you mark the crater itself.

One final logistical note. Do to image size issues, some of the images are almost identical but with a slightly different center. So if it looks as if it is giving you the same image twice, that’s okay. Mark it again and keep going while we try to sort that out.

The crater database that you are helping to build for Mercury will inform the scientific exploration of the  planet. In particular, our science team is trying to determine to what extent the small craters are actually secondary craters, or craters formed when ejecta from an impact rains back down on the surface. That affects how we analyze crater counts to tell us the geologic history.

As always, stay tuned as we add more information to the site and enjoy mapping a new planet with exquisite precision!