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
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 http://terrains.planetfour.org
I would like to share with you our new paper that just got published in January volume of Icarus journal.
The most exciting part of this paper is that HiRISE detected some new troughs in Martian polar areas. The troughs were not visible when the HiRISE observed those locations for the first time in Martian Years (MY) 28 and 29. But when we have commanded HiRISE to take repeated observations in MY 30 and 32, we were rewarded with images of new features that you can see in the animated image below.
The troughs are really small: the whole image is less than 200 m across, while the new troughs are only up to 1 m wide. The total length of them reaches 582 m thanks to their multiple branches.
The new troughs, large enough for HiRISE to detect, are created under the current climate condition – and this is really a big deal. They do look much like spiders: they have different tributaries and resemble the dendritic nature of the large spiders. And they are developing. In turn this means that the large spiders might be developing right now as well. We are still waiting to see topographical changes on the large and fully developed spiders, but we know now that the process is able to erode away quite some ground material. For example, the volume of the material that was moved to create the troughs in the image above is 24 m², they were created over 3 MY, meaning, the process moved 8 m² yearly only in this one example.
The erosion rates like this lets us evaluate the age of the large spiders. They take amazing 1.3 thousands Martian years! It is a long time for a human being, but it is really just a blink of an eye for a geological feature.
We are continuing to monitor these locations to check if these troughs will not be erased in the next years. It well may happen because the new spiders are located very close to the dune fields, and moving sand is capable to cover or sand-blast these small topographical features barely in a year.
I once did a very similar search with Mars Orbital Camera (MOC) images. The camera worked on Mars Global Surveyor from 1997 to 2006. It had 2 sub-systems: a wide-angle camera and a narrow angle camera. The narrow angle camera obtained grayscale images with resolution from 1.5 to 12 m per pixel. It was just good enough to resolve larger spiders and fans.
In 2004 I looked through all MOC images that existed at the time and were located south of latitude -75º. I was hunting for spiders. The result is a list of MOC images that feature spiders and it is now being added to Integrated Database of Planetary Features. It will be available as a layer in JMARS system in a couple of months.
You can see Spiders map on Database of Planetary Features.
When we have a catalog of CTX images with spiders created by you, we will also integrate it into this database! Then everyone can easily navigate around different locations of spider terrains.
We started Planet Four: Terrains with the main goal of finding new regions to study during the upcoming seasonal processes HiRISE campaign. The idea was to have people scour low resolution Context Camera (CTX) images for terrains indicative of sculpting during the seasonal processes produced by never-ending cycle of carbon dioxide ice being deposited on the surface in the winter and that ice sublimating in the spring and summer. We would then select a portion of those areas for further study with high-resolution imaging with HIRISE. With the varied textures of the Martian surface it would be difficult for a machine to do this task, but the human brain is well suited to this task.
We launched Planet Four: Terrains at the end of June as part of the launch of the Zooniverse’s new citizen science platform and project builder portal. Planet Four: Terrains had little less than a year to review 90 full frame CTX images divided into 20,122 subimages or subjects as their known on the website. With your help, the project was able to get through all 20,122 subjects in time, and even put in more images. Thanks to your classifications and Talk discussions, the science team was able to come up with a list of images and locations for further study. We aim to have the HiRSE camera point at these locations and snap images. Some of these locations will be monitored throughout the Southern spring and summer. Right now these locations have been entered in the HiRISE target database. This means that Planet Four: Terrains has successfully achieved one of its prime goals!
Now, Candy Hansen, PI of the project and head of the seasonal processes campaign with HiRISE, will prioritize our targets with the rest of the regions that the HiRISE team wants to study. The first of these should with any luck get images in the next few months. We’ll keep you updated here on the blog.The final list of targets from Planet Four: Terrains is a mix of locations found on Talk and through the classification interface. We’ll have more details as we get closer to the start of Southern spring (July 5th), but we wanted to share one of the new locales,spotted thanks to the volunteer contributions on Planet Four: Terrains, that will be imaged by HiRISE. This specific region shown above was highlighted on Talk. It was noticed by the science team, and we agree it is an interesting area to look at how spiders develop. We’re interested to see how the seasonal fans and blotches over the coming Martian Southern spring and summer. We’re currently planning a sequence of images at this location. CTX has a resolution of 6-8 meters per pixel. HiRISE has a resolution of 30 centimeters per pixel, so we’ll get to see a lot more detail particularly in the structure of the spider channels than what’s current visible in the CTX image above.
This isn’t the end of the project, we’re really just getting stared. Because of your classifications, we’ve found spiders in interesting and potentially unexpected regions so we’ve decided to keep the project going with new locations to review. Help today at http://terrains.planetfour.org
WeMartians is a brand new podcast aimed to engage the public in the exploration of Mars. The latest episode is about citizen science on Mars with Michael talking about Planet Four and Planet Four: Terrains. Listen to Michael (and cameos of other familiar Zooniverse voices) below or on the WeMartians website.
One of the key goals of Planet Four: Terrains is to identify new areas of interest to observe with HiRISE during the seasonal processes campaign so that we better learn about the carbon dioxide geyser process and about how and were spiders and related channels form. You can read more about the particular goals of Planet Four: Terrains here. Over the months we’ve read the discussions and comments on Talk and been making a list of regions to consider from your observations. We’re really intrigued by many of the things you’ve all spotted. Which is fantastic news! Talk has been a huge asset for this work, but we’re also using the classifications from the classification interface as well. I’ve spent the past three weeks putting together a software pipeline to take the multiple classifications per CTX subframe (typically 20 people review each subject image) to identify spiders, baby spiders, channel networks, craters, and the Swiss Cheese Terrain.
Now that the machinery is all together combined with the interesting gems on Talk we’re ready to make our list of proposed new HiRISE monitoring targets. By April 20th I aim t provide the rest of the Planet Four: Terrains science team a compiled list of locations for them to review. Then Anya will input these into the HiRISE planning system where they will be considered with the HiRSE team’s science goals and eventually Candy who wears many hats including Deputy Director of the HiRISE camera and lead of the seasonal processes campaign will prioritize these new areas with the already existing targets in the seasonal processes observing program. We aim to be ready for HiRISE’s first attempt to image the South Pole which is coming up in about 60 days or so.
This is where you come in. We have new images of different areas on the site now. There have already been some interesting images from this set I’ve forwarded to the rest of the team after seeing discussions on Talk. Let’s make a push to classify as much of the new data set as possible before the 18th of April. The more subjects reviewed the greater chance to include those areas at the start of the monitoring campaign. Not to worry though, we’ll also have a few chances to include additional targets later in the Spring Season to the HiRISE monitoring campaign if need be or to the next one.
If you have a free moment, classify an image or two at http://terrains.planetfour.org
I thought for this week’s blog post, I would talk a bit more about what happened in last week’s science team call and what we’ve been up to over the past month or so. Last month was the Division of Planetary Sciences meeting where for the first time, Michael, Candy, Anya, and I have been in a room together. So we had dinner and went through the paper draft and what’s left to do in terms of getting the paper out. Michael’s poster at the meeting showed the first results of the full pipeline run identifying fans from blotches. So the results of that was also discussed during our meeting.
Most of the time we rely on email and team calls to work together. Right now every two weeks we have an hour call between Michael, Anya, Candy and myself. I think they’ve been really important in helping us work together over such long distances as I’m based in Taipei, Candy is based in Utah, and Michael and Anya live in Colorado. It’s our chance to update each other, talk over issues and stumbling blocks, and talk about the data.
Michael’s been hard at work this year getting all the pieces in place to make the final catalog for Season 1 and Season 2. Overall the software pipeline Michael has built works incredibly well, but we still need to check all the edge cases where we might need to tweak the process. I took the task of going through and checking a subset of subjects with the identified fans and blotches plotted compared to the individual volunteer markings to look for any anomalies or issues with the clustering pipeline. The algorithm Michael’s developed takes your classifications and combines them together to identify where there are fans and blotches and based on how many people used which tool (fan or blotch) we determine if the dark region is a fan or a blotch. I did this review shortly after DPS meeting, and Michael and I filled in the Candy and Anya during the call.
Michael’s now working on implementing some changes to his pipeline, and we’ll take a look at those result soon. Now that we’ve got this first pass from the full pipeline, we can start building the codes to make the plots we want for the first paper and look at the distributions of fans and blotches over time and across the different target regions in Seasons 2 and 3. We spent a good chunk of this month’s call talking about what plots would be the most diagnostic. We also talked about the strategy we wanted to use to compare images with different binning/image resolutions. Anya and Michael are going to work on that over the coming weeks. I’ve got some tasks assigned for the next call as well, including using Michael’s catalog to compare to the gold standard dataset the science team generated.
We also talked about the new text Michael wrote in the paper draft, and set a deadline for the rest of us to read it and give back comments. The next full team call will be in early/mid January. We’re getting closer and closer to having a complete Planet Four science paper ready to submit to a journal.It’s nice to see the progress and watch everything coming together. Thanks for your continued clicks. The hardest part is getting the pipeline complete. Once we have this huge step completed, it means we can rapidly produce catalogs for the entire Planet Four classification database and start working on comparing the mapped observations from 4 Mars years of Manhattan and Inca City that you’ve marked. I’m really looking forward to seeing what we learn from that.
A quick update on the first paper. We’re getting closer to having the final clustering procedure nailed down. Once we’ve got that, we can make the final catalog of markings from Season 2 and Season 3 from the millions of classifications we have gathered over the past few years. While Michael has been working on that, I’ve been working on some of the other tables we need to include for the paper. We know what we’ve done and have good knowledge of the HiRISE data, but we need to make sure it’s clear in the paper so that any researcher or reader has all the information needed to use the catalog of fans and blotches we’re generating thanks to your clicks. To do that we’re going to put in a table that summarizes all the relevant info about the HiIRSE observations from Seasons 2 and Season 3.
The easiest way I found to do this is to grab this information from the headers of the reduced single HiRISE images non-map projected images with the spacecraft pointing information that we created from the raw HiRISE observations. The HiRISE team reduction pipeline produces the three color band mosaics that we dice up and show on http://www.planetfour.org but since they don’t include the spacecraft information we had to build a single filter version ourselves where we added a few steps to the process that would allow the information needed to get the location on the South pole and the spacecraft information into the image headers. This is what Chuhong worked on last summer.
So I took a script written by Gauri adapted from Chuhong’s code to get the other relevant info like imaging scale, north azimuth, solar longitude from the single filter image headers and stick it in a mysql (a database interface language/setup) table.Then I spent a bit of time writing a code to read the table I created and output it in the format needed for the paper. We’re writing the paper in a format known as LaTeX. I spent an afternoon getting the format correct so that table file would compile. You can glimpse part of the results (the first few lines of the multi-page table) below. I still need to reduce the number of decimal places outputted in certain columns, but the basic information is there. We’ll be including a version of this table in the paper text or supplementary material.
Today we have the last post from Gauri Sharma who is spent her summer working on Planet Four as part of the ASIAA Summer Student Program. Gauri gave a talk at the end of August detailing her work with boulders and developing a pipeline to find the same position in one Planet Four image in others shown on the site. Below Gauri presents her talk slides and her project. Thanks Gauri for all your help this Summer!
I am gonna introduce you some of the features found on Mars’ South Pole and tools used to study these features. I will also tell quick logical science behind those features according my research in these last two months.
During the winter on South pole a, CO2 ice slab forms over the pole is nearly translucent and ~1m thick. When the ice slab forms, it comprises of frozen carbon dioxide and dust and dirt from the atmosphere. Below the ice sheet is layer of dust and dirt.
When the spring comes sunlight penetrates the CO2 ice slab, and the base of the ice cap gets heated. The temperature of the ice at the base increases causes CO2 sublimation. Sublimation of CO2 creates a trapped pressurized gas bubble beneath the ice layers, These beneath pressurized gas bubbles continuously pushes the upper layers of ice and at one point ice slabs get crack and pressurized gases vent out. A jet like eruption or geyser takes place. It is thought that material (dirt and dust) from below the ice sheet which has been taken by pressurized gas is brought up the surface of the ice sheet and is blown by the surface wind into a fan shape.
When there is enough wind on surface to blown the geysers material fans appears on surface and surface looks like fig1.
If wind is not much effective or not blown then geysers material deposits near the geyser source and a black spot appears on surface called blotches (shown in fig2).
Also during the spring and summer when the geysers are active, the trapped carbon dioxide gas before it breaks out from under the ice sheet is though to slowly remove material and carve channels in the dirt surface. In the mid summer when CO2 fully get vaporized channels are empty cracks. This is annual process of over time produces erosion on surface and channel network looks like spiders (or their official name araneiform).
In every spring and summer season, hundreds of thousands of fans wax and wanes on the Martian South Pole. These features have been captured by then HiRISE camera. HiRISE camera is onboard on Mars reconnaissance orbiter since 2005.
These are the sample images captured by HiRISE camera.
During analyzing of these images, scientists found difficulties, Automated computer routines have not been able to accurately identify and outline the individual feature. But scientists thought a human eye eventually can distinguish and outline these features and shape them. So, A group of scientists created Planet four website purposefully for research on Mars by public help.
This is how, Planet Four website looks like. Working with Planet Four is very easy, just sign up in Planet Four website and take in part of classify shapes on surface. Before getting started they provides a short intro to let you know “How to mark, and useful tools to classify features”. Volunteer classification are collected together and researchers combines these classifications (markings), and they found these markings produces an extremely reliable, fruitful results about features founds on Mars surface.
In slide 10, we seen Planet four images looks different from real images taken by HiRISE camera. Since HiRISE image is huge in size. So for proper analysis and accurate outlining Planet Four team made sub images of HiRISE images and kept them in Planet Four website, we call them tiles.
For my project Planet Four was one of the most important tool. I use Planet Four tiles to examine boulders. Boulders are one of the more interesting objects on Mars surface, and in the South Pole regions monitored by HiRISE only one area seems to have boulders. This region has been dubbed ‘Inca City.’ The boulders in Inca City are likely impact produced. Boulders are Interesting because we think they can help be a heat source of geysers formation. I am looking at how fans are associated with boulders more often than not and has been captured by HiRISE. I studied how surrounding of boulders changes time by time, are they really takes part as the source of geyser formation”.
I chooses some 35 tiles those contains BOULDERS and marked all BOULDERS (shown in fig2). After marking Planet Four provides a makings csv file. That contain your marked BOULDER x and y position and corresponding tile name.
To analysis surrounding of BOULDERS over a time, I need to search over the HiRISE 5year database with the help of markings csv received by Planet Four. Since HiRISE database contain more than 1 lacks tiles. Doing search manually and find useful data and then calculate information, collect belonging files and group them for looking yearly changes seems terrible.
So for this purpose I created a pipeline that can do all this in seconds. This is a very powerful pipeline that Planet Four team doesn’t have before me.
These are the results of my pipelines.
Images in blue box clearly shows, During a season as the month changes surrounding of boulders changes (fans wax and wanes) boulders gets covered with fans material and in next season again boulder start visible.,,,