Archive by Author | Meg

Working on Preliminary Planet Four: Ridges Results

I’ve been working on getting some preliminary locations of  polygonal ridges in the completed Planet Four: Ridges subject images. I thought I’d share. Here’s locations where 7 or more volunteers who reviewed a subject image and said there were ridges present. We have 10 people review each of the subject images on Planet Four: Ridges.

I’ve made some figures to show the locations of these subject images. Below are MOLA shaded elevation maps with the CTX images we searched outline in blue. The red boxes are the prelminary locations of polygonal ridges, based on the criteria discussed above,


And zoomed in more


We’ll use take these locations and eventually compare to the maps of minerals to further explore the formation mechanism for poylgonal ridges in the area. Stay tuned.  More to come as we finish the next set of images live on the site. Help classify an image or two on Planet Four: Ridges today at

Where Planet Four: Terrains Might Go Next

We’re now 60% through the third set of CTX images on Planet Four: Terrains. We’ve started to think about where we want to search next. We want to continue to fill in the area searched from -70 N latitude to the Martian South Pole. I’ve been coming up with the CTX image selection since the launch of Planet Four: Terrains. I wrote a code that goes through the list of publicly available CTX images and tries to pull  out a well balanced distribution of ice-free CTX observations across specific latitude and longitude bins. I thought I’d share my proposed set of new CTX images to search. I’ve sent this list of images to the rest of the science team, and I’m awaiting their feedback. The new set if accepted by the team, will fill in gaps in our coverage and especially between -70 and -75 N latitude. When we have a final list of CTX image to search after dataset 3, we’ll update you here on the blog.

Color Code for figures below.

Red= first dataset at launched and used in our first paper

Green= second dataset

Magenta = third dataset that expanded out to -70 – currently being reviewed on the site

Gray = 4th proposed set of CTX observations to search


The CTX image outlines are overlaid on an elevation interpolated map. Latitude and longitude lines are in 10 degree intervals for above and below.  The colors below represent geologic units, but for this comparison we’re focusing on spatial distribution and coverage. More details can be found here


First Planet Four: Terrains Science Paper Submitted

It is my great pleasure to announce that we have written up the first science results for Planet Four: Terrains in a science paper. After months of writing an analysis we have a final draft ready, and last night I  submitted it to the journal Icarus to be considered for their Mars Polar Science special issue.

Right now the manuscript is in the hands of the editor.  After some checks, the paper should be sent on to two anonymous reviewers. In what we call the peer review process, these reviewers are independent researchers in the field who read the paper, critique it, and provide feedback which the I will have a chance to respond to and make some or all the recommended revisions to the paper. This process can have a few rounds of iterations with the referee. Ultimately, the referees will recommend to editor of whether the paper  merits being published, and the editor makes the final decision.

So now we wait. The manuscript is in the hands of the editor at Icarus who is likely selecting and contacting possible referees. In a month or so we should get back the first round of reviews. I’ll keep you posted here on the blog. So stay tuned! This paper focuses on the distribution of spiders and swiss cheese terrain from the data on the site at launch. We’ve also included analysis of some of the HiRISE  observations taken of some of these new spider locations. I’ plan to write a fully summary of the paper results once the paper is hopefully accepted in a few months.

Thank you to all of you who have participated in Planet Four: Terrains. We could not have done this without you. We appreciate the time and effort you put into this project. Thank you for collaborating with us.

We also want to thank the Zooniverse team for giving the research team early access to their Project Builder platform to build and design Planet Four: Terrains.

Planet Four: Terrains is not finished. This is just the beginning. We’ve expanded out search more areas way from the South Pole. Many of those images are in need of review. So jump in and help explore Mars today at

Sand Dunes in Arabia Terra

I wanted to point out some features you might have noticed in the Planet Four: Ridges images. Dark wiggly blobs as shown in the images below are actually sand dunes on Mars.






We’re showing images from orbit, but to give you a sense of what some of these might look like from the ground, here’s a selfie of Mars Curiosity at “Namib Dune”, part of the informally named Bagnold Dune Field located in Gale Crater. I learned recently that on Mars, sand dunes are black because they are made of ground up  basaltic lava rocks, just like black sand beaches of Hawaii are.


Image credit: NASA/JPL-Caltech/MSSS

More Planet Four – Introducing Planet Four: Ridges

Today we have a guest blog by JPL research scientist Laura Kerber.  Laura studies  physical volcanology, aeolian geomorphology, wind over complex surfaces, and the ancient Martian climate,

The surface area of Mars is almost the same as the area of all of the continents on Earth. Only a tiny fraction of these vast, untouched lands have been explored by rovers. Of the rest, much of it has still never been seen up close by human eyes. Today we’ve launched  Planet Four: Ridges, and we are asking for your help to explore a particularly interesting part of the Red Planet. The goal is to find polygonal ridge networks, which are intersecting lattices of thin ridges enclosing polygonal shapes.

A polygonal ridge network in the eastern Arabia Terra region of Mars. This image shows an area about 4 kilometers across

A polygonal ridge network in the eastern Arabia Terra region of Mars. This image shows an area about 4 kilometers across

Some of these ridges can be up to 50 meters tall, and from the surface would appear like the ramparts of an enormous fortress. Networks of ridges are usually formed via the filling of fracture networks either with lava, wind-blown sediment, or mineral deposits from circulating ground waters. These fractures are then transformed into ridges as the softer units around them get eroded by the wind. Your classifications on this site will help researchers find these networks and compare them to distributions of other features, such as mineral signatures, ancient valley networks, and dried up lakes. The images you see here are taken using the mid-resolution (6 meter per pixel) Context Camera (CTX) in orbit around Mars. Each participant views portion of images and decides whether or not there is a polygonal ridge network in the frame. We collect together everyone’s views on each image and this helps us find new ridge networks to study. The ridge networks can be subtle, but human eyes are well suited for pattern-finding, which is why we rely on you over computer algorithms.

More than 3.5 billion years ago, the climate of Mars was much different than it is today. The surface of Mars shows evidence for hundreds of lakes, and thousands of kilometers of flowing rivers. During this time and earlier, warm groundwater may have circulated in the Martian subsurface, potentially providing a protected home for early Martian life. One piece of evidence for groundwater during this period is the presence of clays that are deep in the crust (often visible in the central peaks of impact craters). Another is the presence of mineral veins, which are formed when warm water carrying elements in solution deposits minerals on the walls of fractures. Hot water or steam can also alter wall rocks of fractures, causing the walls to harden compared with the surrounding material. Later, after the crack cools, the minerals become harder than the rock types that surround them, so that as the surrounding unit get eroded by the wind, what was originally a fracture becomes a ridge.


A ridge network filled with the mineral gypsum located in the Lut Desert of Iran, one of the world’s hottest and most lifeless deserts

A close-up of a Lut Desert gypsum ridge

A close-up of a Lut Desert gypsum ridge

Not all polygonal ridge networks are formed due to circulating groundwater, however. Sometimes open cracks on the surface get filled with windblown dust and sand, and that part gets preserved. Lava can also fill up cracks, either as it rises through the subsurface as magma, or if it is flowing along and drips into a fracture network. Finding all of the ridge networks on Mars helps us untangle which networks were formed by which process, all the while learning more about the intriguing wetter period in Mars’ history. This project focuses on the Eastern Arabia Terra region of Mars, where several ridge networks suggestive of mineral veins have been found.

A crack that has been hardened by hot steam escaping. It has since been brought into relief by the erosion of the surrounding rock. Campo de Piedra Pomez, Argentina.

A crack that has been hardened by hot steam escaping. It has since been brought into relief by the erosion of the surrounding rock. Campo de Piedra Pomez, Argentina.

As the project continues, we hope to share more background information on these interesting features here on this blog. Meanwhile, why not go find some ridge networks? Visit to start looking.

Four Years of Planet Four

Image Credit: catbeurnier- Flickr - original photo (

Image Credit: catbeurnier– Flickr – original photo

January 8th, marked the 4th anniversary (well at least in Earth years!) of the launch of  the one and only original Planet Four. We wanted to thank you for being on this journey with us for the past four Earth years. Our first science paper seems to always be delayed, but I and the rest of the science team are dedicated to getting this paper out the door. The science team is virtually meeting on Wednesday to discuss what I hope is the freezing of the development of the classification clustering algorithm. That’s the hurdle in our way, and over the past Earth year Michael has made great strides dealing with the major issues we needed to tackle to get the science from your clicks. Thank you for your time and effort on the site. We still need you, and new data from Manhattan Season 5 is now live on the site. So go check it out and classify some fans and blotches at

Planet Four has been able to show that a citizen science approach beyond crater identification with Mars orbital imagery works. The science team was invited this past fall to showcase Planet Four at a workshop focused on citizen participation in Mars exploration hosted by NASA Headquarters. Planet Four’s successes, has spawned other Mars Zooniverse citizen science projects: Planet Four: Terrains (which has already produced results with Mars Reconnaissance Orbiter pointing HiRISE and new locations on the Martian South Pole) and a  birthday gift if you like that is coming tomorrow! Stay tuned to this space for more tomorrow! We can’t wait to share this new endeavor with you all.

Thank you for the past four years and onward to Year 5!

Before the Sunlight Leaves

A quick update on Planet Four: Terrains. I’m working on the first paper draft and planning on submitting it to a science journal by early February with any luck. Currently the draft is being iterated on; I’m incorporating comments and feedback from the rest of the science team. The paper focuses on the distribution of spider features on the South Pole based on Planet Four: Terrains assessments. So stay tuned for more on that over the coming months.

In the meantime, I’ve also processed the subject images currently retired from the newest set of images on the site. We’ve found  interesting areas with spiders and baby spiders that we’d like to get a closer look at. We’re hoping that HiRISE will image these over the coming months. The days on the South Pole are getting shorter. May 5th 2017 marks the official start of Southern Fall Equinox. In a few months time, we’ll have to wait approximately 2 Earth years for an opportunity to image interesting regions of the South Pole with HiRISE found by Planet Four: Terrains.

Processing the retired subjects from the current set of CTX images on the site, we found four new regions of interest thanks to your collaboration that we want to take a better look at. We  have requested HiRISE imaging. So the race is on to get through as many of the P4: Terrains subject images as we can before there won’t be enough sunlight for HiRISE observations. If you can spare some time, place help classify an image or two for spiders, baby spiders, channel networks, swiss cheese terrain, and craters on

New Data on Planet Four

Thanks to all your help, we’ve completed the review of the  Season 4 observations of Giza, Ithaca, and Macclesfield. We have new observations from Season 1 from a two different areas around the South Pole now uploaded and live on the site. These areas are nicknamed Starfish and Caterpillar for the spider morphology that have been seen in those areas. Caterpillar is  much further  away from the South Pole than some of the areas you’ve reviewed here before.


Locations of the Seasons 1, 2, and 3 of the HiRISE South Pole Monitoring Campaign – Image Credit: Michael Aye

It will great to see how the numbers and sizes of fans and blotches in these two areas compare to Manhattan, Macclesfield, Inca City, Ithaca, and Giza. Dive into these new images today at

New Data on Planet Four

Over the past many months you’ve been reviewing Season 1 observations of areas nicknamed Macclesfield,  Giza, and Ithaca. We’ve now finished the current set of data live on the site. We’ve recently prepared and uploaded Season 4 observations of Giza, Ithaca, and Macclesfield so that we can see how the carbon dioxide jet and fan formation processes evolve over several Mars years in these areas.

Thanks for all of your help, we couldn’t do this without you. The clustering algorithm to combine all of your markings together is nearly finished. We’re making hopefully the last tweaks and improvements. This means that over the next six months to a year we’ll be able to compare the results from your classifications of these new images to Manhattan and Inca City, where we already have four Mars years of HiRISE images classified on Planet Four.

Dive into these new images today at

New Metadata Feature on Planet Four: Terrains Talk

The latest set of Planet Four: Terrains images comes with some added bonus features on Talk. Thanks to upgrades in the Zooniverse platform we can now display additional information with the metadata icon on Talk that won’t appear in the classification interface. So we can share the original parent CTX image name and a link to the image on Talk for your further investigations. We don’t show this information in the classification interface in order to keep the classifications free from any potential causes of bias.

So now when you classify, if you want to check out the full frame CTX image the subject is derived from, just click on the ‘Talk’ button after submitting your classification. This will bring you to the Talk Subject Page for this subject. Then if you click on the ‘i’ icon below the image,the metadata window will pop up (see below)

Screen Shot 2016-08-22 at 11.43.11 PM

Screen Shot 2016-08-22 at 11.21.34 PM

!filename is the internal filename the Planet Four: Terrains used to name the subject when we generated it. !CTX_filename is the name of the full frame CTX image the subject comes from. !Public_CTX_link will take you to the MRO Context Camera Image Explorer where you can view the image (the link was working earlier to directly show the CTX image but isn’t working for me at the moment. If  you have any issues you can always copy and paste the CTX filename into the search box and that will bring up the image)