How To Take Part

We need your help to explore the lunar surface, by answering a series of questions about what you see. The most important thing to remember is that we've chosen tasks that are best done by humans rather than computer, so please don't spend much more than a minute on a any single image.

Crater Survey Tutorial

First off, please watch this short video demonstrating the Crater Survey interface.

In this task, you'll be shown a randomly selected image of the lunar surface. Your first task is to identify any craters that you can see in the image.

To mark them, click on the 'Crater' button, and click at the centre of each crater that you can see. The circle that appears is the size of the smallest crater that we care about for this image so ignore anything that's smaller than that.

How the craters appear will depend on whether it was morning, midday or evening — the shadows will change dramatically over the course of a day. To give you a guide, the picture at the bottom left of the screen will tell you which way crater shadows point in each image.

Once you've marked all the craters, you can click on the ellipse to stretch and move them so they mark the right size of crater. Don't become a perfectionist — just spend a few seconds per crater. If you've made a mistake or change your mind, just select the ellipse and hit the red cross.

Once this is done, the next stage is to look for boulders surrounding the craters (you might find it easier here to click the 'eye' to turn off temporarily the ellipses you've just carefully drawn).

If none of the craters have boulders, then move on. If any do, click on the ellipse and select 'blocky crater' and then either 'none', 'some' or 'many'. When you've made your selection the ellipse will be marked with an exclamation mark.

Finally, don't forget to take time and look around the landscape! You can use the square tool to highlight regions of interest — we've provided examples of what we're looking for below.

When you're done, click 'submit' to save your hard work to the Moon Zoo database and to move on to the next part of the lunar surface. Enjoy exploring.

Boulder Wars Tutorial

Boulder wars is simple: we want you to compare two random images and decide which has the most boulders. If neither image has any boulders then click the 'No boulders' button in the middle. Watch the short video below to see a demonstration of the Boulder Wars interface.

If you'd like to see some examples of bouldered areas of the lunar surface click here.

Extended Crater Survey Tutorial

In this task we show you a photo of the Moon’s surface. We won’t tell you what the sizes of the features are — you might well be looking very close in to a scale of a few metres across or you might be looking from very far away at an image that is several kilometres across. Size doesn’t matter for what you have to do.

There are several parts to this task and we recommend stepping through the tasks in the suggested order.

Step 1: Where are the impact craters and how big are they?

Lunar impact craters very often have shadows inside depending on if the image has been taken in the morning, midday or evening. The picture at the bottom of the Moon Zoo screen will tell you the direction the shadows should be pointing. Some of the craters will have very well‐defined rims, others will have rims that are very hard to see.

You can see some examples of old, eroded craters here. Your job is to tell us how big you think these impact craters are. We want you to look at all the features that look like holes in the photo on screen. These holes are impact craters that formed when a meteor or comet crashed into the Moon.

  1. Take a look at the bottom of the screen to check the example image of what a crater with shadows will look like in this image.
  2. Are there any impact craters?
  3. If there are no craters or the image is completely black then click the 'SUBMIT' to move onto another image.
  4. Now look carefully at the image and spot where you think the craters are. If you have to debate with yourself if the feature is a crater or not then don't include it.
  5. If it isn't already active, click on the 'Mark craters' tool at the top-right.
  6. Click on all the places in the image where you think there is a crater. If you click, hold down the mouse button and drag the cursor you can resize the ellipse to fit the crater rim. The small ellipse under your mouse cursor is the minimum size of crater we want you to measure, so if the crater you have spotted is smaller than this minimum then don't mark the crater. If you have already marked a crater you may need to delete the placement if it is smaller than the minimum size (see step 9).
  7. Once you are happy that you have marked all your ellipses on top of the impact craters in the image (above the minimal crater size) you can change the size or delete them individually...
  8. Click back on the 'Mark craters' to end your ellipse dropping session.
  1. To delete an ellipse — select the ellipse you have dropped, then hit the cross button. The crater will disappear. If you delete an ellipse by mistake then you can use a combination of the ctrl + z keys (Windows) or command + z (Mac) to undo your change.
  2. To change the size of the ellipse — select it on the main screen, then using the control tools that appear around the edge you can (i) drag it out to make the circle bigger, (ii) stretch out the circle to make an elliptical shape and (iii) rotate the ellipse to fit exactly over the crater edge.
  3. If you have placed one ellipse on top of another and want to change the dimensions of the underlying ellipse — click on the top ellipse, now click on the 'hide current' button (this will make the top ellipse disappear), click back on your lower ellipse and make your adjustments, when you are happy click back on the 'show all' button and the top ellipse should reappear.
  4. Adjust all the ellipses until you are happy that they are placed over the crater rims. Don't spend too long doing this — just a few seconds for each ellipse will do — we only need a rough idea of how big the craters are! There often won't be a 'correct' answer. Just pick the shape that seems best and move on to the next crater. If you want to go and drop any more ellipses go back to stage (4).
  5. When you are finished with the image then move onto the Step 2.

Eroded craters

Eroded_1 Eroded_2 Eroded_3
Eroded_4 Eroded_5 Eroded_6
Eroded_7 Eroded_8

Step 2: Do any of the craters have boulders or blocks in them/around them?

It is likely that there will be very few craters with blocks or boulders so don't worry at all if you can't spot any! It is a bit of a bonus if you can find one... Have a go yourself now... hold your mouse over the lunar images below to find out if we think the crater is blocky or not.

We want you to go back and look at all the craters you have identified.

  1. Select the 'Hide all' button to temporarily remove the ellipses you have drawn and take a look at the craters underneath.
  2. Do any of the craters have blocks or boulders in them? If you are not sure what a boulder or block will look like you can see some examples here.
  3. Select the 'Show all' button to once again reveal all of the ellipses you have drawn
  4. If none of the craters you have drawn over have blocks or boulders then move onto Step 3.
  5. If one of your craters has blocks in or around it then click on the ellipse you have drawn over that crater. Then select the 'Boulder' button. This button will prompt you to choose what types of blocks/boulders the crater has. You have three choices (1) 'none' (oops you made a mistake this crater doesn't have any boulders); (2) 'some' (the crater looks a bit like the example provided — it has only a few boulders in and around it) and (3) 'many' (the crater has lots of boulders like the example provided). If you want to check what your blocky crater looked like — toggle the 'Hide current' button to temporarily remove the ellipse and bring it back again. Choose what sort of blocky crater you have identified and when you have made your selection an exclamation mark (!) will appear over that crater.
  1. You can always redraw or delete this ellipse in the same way as described in Step 1.
  2. Repeat these steps for any of your other craters with blocks/boulders.
  3. When you have finished then move on to Step 3.

Bouldered crater examples


Boulders_many_1 Boulders_few_1 Boulders_none_1

Step 3: Is there anything odd?

We want you to take one final look at the image. We would like you to spot anything you think might be a 'scientifically interesting' feature. However, we don't want you to go crazy spotting lots of things that are very common on the Moon — so take a look at some of the examples below we have written as a guide. Here are some examples of the things we really want to look for.

Bench craters

Bench_crater_1 Bench_crater_2 Bench_crater_3

Flat-bottomed craters

Flat_1 Flat_2 Flat_3

Dark haloed craters

Dark_haloed_1 Dark_haloed_2 Dark_haloed_3

Fresh white craters

Fresh_crater_1 Fresh_crater_2 Fresh_crater_3

Elongated pits

Elongated_1 Elongated_3 Elongated_2

Linear features

Grabens, cracks and straight rilles

Linear_1 Linear_2 Linear_3

Boulder tracks

Boulder_tracks_1 Boulder_tracks_2 Boulder_tracks_3

Crater chains

Crater_chain_2 Crater_chain_3 Crater_chain_4

Sinuous channels

Sinuous_1 Sinuous_2 Sinuous_3

Also look out for...

Spacecraft hardware

We want you to keep an eye out for bits of spacecraft debris that are scattered across the lunar surface. The LROC camera images that Moon Zoo uses are of such high resolution that you may be able to even spot astronaut's footprints that were left forty years ago! This is a very hard task as these objects and crash sites are very small (metres to tens of metres), but think of it as an extra challenge whilst you are measuring craters and finding other interesting geological phenomena!

The Apollo lunar descent stages and landing sites

Whilst there are only six sites on the Moon where people have visited these are included in the Moon Zoo images you will be looking at. Keep an eye out for a bright object that looks a little like a boulder, surrounded by a dark halo (disturbed lunar soil) and often also surrounded by tracks that could be astronaut or r

Apollo 11 | Apollo 12 | Apollo 14 | Apollo 17

The Soviet Luna landers and rovers

These are likely very very tricky to spot as the Luna lander base stations are very small and will often look like bright boulders. The following ASU websites are a good guide to what the Luna landers look like in LROC images, view them here and here.

Hard lander crash sites

Missions like the US Ranger series were designed as 'hard lander' missions that would end their life by crashing into the lunar surface. In a similar manner upper rocket stages of the Apollo missions were slammed into the lunar surface to help provide seismic events detectable by Apollo geophysics experiments. To spot these types of crater sites keep your eye out for very fresh (bright) craters with bright rays. If you spot one please do see if you can measure the crater size so we can see how big these man made impact craters are! Some examples of what to look out for:

Generally weird stuff
Weird_1 Weird_2 Weird_3

If you think you have spotted something we might be interested in here is what to do:

  1. Select the square feature tool.
  2. Click on the screen where the feature is.
  3. Select from the drop down menu what you think the feature might be.
  4. Resize the region of interest (rectangle) over the area of your interesting feature or you can delete it if you change your mind.

It is very likely that you won't spot one of the features we are looking for in every image so don't worry if you can't see anything worth noting!

Step 4 — Favourite?

If you want to save this image to your favourites then click on the 'star' button at the bottom-right of the interface.

Step 5 — Finish!

Click on the 'Submit' to finish this image completely! Your data will then be saved to the Moon Zoo database.

Extended Boulder Wars Tutorial

Step 1 — Is there anything odd?

Take a look at both images carefully. We would like you to spot anything you think might be a scientifically interesting feature. However, we don't want you to go crazy spotting lots of things that are very common on the Moon — so take a look at some of the examples for the crater marking interface we have written as a guide.

If you think you have spotted something we might be interested in here is what to do:

  1. Select the square feature tool.
  2. Click on either image where the feature is.
  3. Select from the drop down menu what you think the feature might be.
  4. Resize the region of interest (purple rectangle) over the area of your interesting feature or you can delete it if you change your mind.
  5. Continue spotting any other features in either image until you are happy you have spotted everything interesting.
  6. Move on to Step 2.

It is very likely that you won't spot one of the features we are looking for in every image so don't worry if you can't see anything worth noting!

Step 2 — Which image has more boulders?

This is an easy task! We want you to decide which of the two images has more boulders or blocks. Here are some examples of what blocks and boulders on the Moon look like in close up — they are often quite easy to spot as they are small (10 image pixels across or less) and will (i) often have a bright white spot on top and (ii) a black irregular shadow on the opposing side. Once you get your eye in you will soon spot them.

Examples of boulders

Boulders_1 Boulders_2 Boulders_3
Boulders_4 Boulders_5 Boulders_6

Now you know what a boulder looks like, take a look at both images and quickly decide which image has the most boulders and click on the button underneath that image stating 'Most boulders'. If neither image has any boulders then click the middle button that states 'No boulders'. You don't need to count the number of boulders or spend a long time deciding — in most cases it should be easy to decide — we just want a quick decision.