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SpaceX completes 1st round of Starship’s Mars landing site images

All locations photographed of the candidate landing region for SpaceX's planned Mars missions

On August 28, 2019 I broke the story that SpaceX is beginning to obtain images of candidate Starship landing sites from Mars Reconnaissance Orbiter (MRO).

It now appears that SpaceX has completed its first round of Starship requests from MRO. In the image releases from Mars Reconnaissance Orbiter (MRO) since September, only three new Starship locations were taken, and all three were the unreleased candidate sites I noted in my September 16, 2019 update.

Below is the full list of all of the Starship images, their locations indicated on the map above by the numbered white boxes:

With the release of these last photographs, the initial list of proposed images of candidate Starship landing sites on Mars has apparently been completed. No additional images at any other locations appear to have been suggested. The MRO science team has taken stereo images of each one of the nine locations, eight of which were in Amazonis Planitia, and one in Phlegra Montes.

This however is not the first round of pictures requested by SpaceX of the Arcadia Planitia region in connection with the company’s desire to land spacecraft on Mars.

In 2017 SpaceX also requested about a dozen images for its then proposed Red Dragon mission, where they would use the Falcon Heavy to send a Dragon capsule to Mars. They abandoned this effort, partly because NASA did not want them to spend time and money on a test program to develop vertical landing for its Dragon capsule, and partly because they decided to shift gears toward their giant reusable Starship/Super Heavy rocket.

These Red Dragon images are indicated by the cluster of black boxes near Starship image #4. Based on their clustering, it appears that this location was the site that SpaceX had decided to send Red Dragon. The larger scatter of Starship images suggests the company is still not sure where it wishes to land that more advanced spaceship, and is reviewing other nearby locations for options.

The scattering of images and the lack of full coverage, however means that this first round is entirely insufficient to plan an actual landing. This is not a surprise, nor is it a mistake. This round is clearly a first look, to obtain a preliminary idea of what is there to help narrow their choices. Once they have reviewed these images I expect SpaceX to pick one to three locations and then focus its image targeting around these in order to determine their prime landing site.

Why is SpaceX so focused on this region for its future Mars’ missions? We can get a clue from a 2015 NASA workshop, focused on coming up with a reasonable list of first candidate human landing sites on Mars. That conference resulted in a set of 31 candidate human landing sites, several of which were in Arcadia Planitia to the west and east of Erebus Montes.

Though most of these talks focused on the scientific value of each candidate site, the presentations about Arcadia Planitia all noted its abundant ice. One talk noted how this region had craters with ice within them, as well as lots of circumstantial evidence that ground ice was only a little bit below the ground. The craters were what scientists have dubbed “expanded craters,” whereby the sublimation of the ground ice caused the development of an outer depression surrounding the crater itself.

Another presentation pointed out that the mounds near Erebus Montes all have ice rich aprons, making access to water once again relatively easy. As Donna Viola of the University of Arizona noted, “I think you could dig anywhere to get your water ice.”

A third presentation, for an area west of Erebus Montes dubbed Phlegra Dorsa, was different in that it focused not on the scientific value that the site offered but the resources it made available to settlers. For example, the presentation noted the advantageous conditions at the site for working there. The region not only had significant ground ice, an essential resource for future settlers, it also had few rocks and low dust, making it a good place to land and work.

The lead author, Don Barker, was at the time a human spaceflight engineer who had spent twenty years working on the International Space Station. Though he was then also a PhD candidate in planetary geology, his interests leaned toward the engineering. “Most people at the conference focused on the science, which isn’t surprising when you have room full of scientists,” he explained. “I went for resource first, science second.” His thinking was that “if you can build it, they will come.”

It appears that SpaceX is following Barker’s approach as well, and in doing its own research have come to similar conclusions about the region near Erebus Montes. This location has all the right ingredients for a first human settlement: flat terrain for landing, accessible water ice for resources, low dust to ease the working conditions, and a low elevation and relatively low latitude (40 degrees) for a more benign climate.

Expanded crater at Starship candidate human landing site
Click for full image.

The image to the right provides us a typical example of what SpaceX is finding here. It is a cropped section of photo #8 in the Starship list above, and was the last one obtained for SpaceX by MRO. Colin Dundas of the U.S. Geological Survey’s Astrogeology Science Center in Arizona and a co-author for the second paper above, explained that the crater shown is an expanded crater, suggesting the presence of ice at shallow depth. He also noted to me that “it’s possible that other features in the image, such as pits and scarps, are produced by similar degradation processes.”

Based on all this research and the image locations being chosen by SpaceX, we therefore might someday hear a pilot of Starship take a breath and then announce to the world, “Arcadia Base here, the Starship has landed.”

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On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

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  • Michael

    A thought occurs to me. Something the Apollo guys never had to worry about.

    What happens if you spend months getting to Mars and your landing spot is smack dab in the middle of a sand storm?

  • Michael: Any trip to Mars will likely go into orbit first, so they will merely wait for the storm to clear before heading down. If they don’t have that capability they are going too soon.

    Also, Martian sandstorms are relatively harmless. They lower the amount of light (which shuts down solar powered spacecraft like Opportunity), but the amount of material being thrown about is quite tiny. And the thin atmosphere means if you stood there you’d hardly feel the wind.

  • Michael

    Robert: thanks for the information. I assumed they would go into orbit first but it was my understanding that sand storms on Mars could last for months. It sounds like with the appropriate sensors you could just pass through the thing.

    It’s nice to know that this is not a major issue other than maybe visibility on landing.

    Guess I was influenced by the opening of The Martian.

  • Michael: I suspected The Martian was guilty here. While a relatively good movie, that dust storm at the beginning was stupid.

    Note also that the soil of Mars is likely to be quite toxic. In the first science presentation I linked to above about finding candidate Martian landing sites, the scientist very specifically noted that it will be a very bad idea to grow potatoes there. She was clearly referring to this movie.

  • wayne

    MacGuffin: “an object, device, or event that is necessary to the plot and the motivation of the characters, but insignificant, unimportant, or irrelevant in itself.”

    Perchlorate salts + high energy cosmic rays = pretty much sterilize the surface.
    On the upside, one can make rocket fuel from perchlorates.

    Total Recall
    “You blabbed Quaid, You Blabbed About Mars!”

  • I read an interview with Ridley Scott ,(director of ‘The Martian’) where he said he knew the opening scene was, uh, overblown, but missions don’t bail on a zephyr.

  • David

    Even the author of the Martian probably knew, late in the book (omitted from the movie), Watney has to drive through a dust storm, and it’s a major plot point that he doesn’t even realize it for a couple sols, until he eventually figures out that visibility is slightly reduced in one direction, and his solar panels haven’t been giving the usual wattage the last few days…

    The author did write this “live” where readers were getting to read chapters as he wrote them, so he may have done the initial storm, then gotten feedback that it was unrealistic, or he may even have known to start, and just let it slide for “the needs of the plot outweigh the needs of the scientist…”

  • A. Nonymous

    The author has basically admitted that it was a McGuffin, completely done in order to set up the story.

  • wayne

    Andy Weir at NASA Ames
    “How Science Drove the Plot”
    2015 Summer Series

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