Mars Feature, ~13.3°N, 115.5°W
So claims the website “UFO Sightings Daily.” I was alerted to it by Sharon’s Doubtful News site.
I know I said my last post would be my last pre-TAM post, but given that my workshop is on image analysis and how to investigate image-based claims, well, this one was easy and I thought I’d write about it. And I’m going to assume for purposes here that you’ve gone to one of those two links and read a bit about this.
Investigating the Claim: Find Original Images
The first step to investigating a claim like this is to try to find the original image, or the location of the image on the planet. Fortunately, this is a feature on Mars, and the website has provided the coordinates: about 13.5°N and 115.5°W.
As an astro/geophysicist who got his Ph.D. studying images of Mars to study craters, I know of many different ways to find images of locations of Mars. My normal go-to website is Arizona State University’s Mars Global Data portal. It’s fairly exhaustive, letting you use a (admittedly small) map of the planet to find images from over half a dozen different image sources at a huge variety of resolutions. I do not use things like Google Earth because of the way it resamples and stretches images and I don’t like that it caches everything on your computer, taking up hard drive space, and it does not have all the latest data.
What I did was go to the “Webmap” of CTX data. CTX stands for “ConTeXt” Camera on board the Mars Reconnaissance Orbiter. It has a very large, almost global coverage of the planet at a very good ~6 meters per pixel scale. Probably around 70-80% coverage at this time (it’s still in operation and returning data). It’s my go-to source for stuff like this and my work in general. After finding the area, here’s the most zoomed-in you get on that area.
The slanted rectangles are approximate image footprints. By clicking the mouse-arrow tool and then clicking on them, little thumbnails show up below the map. You can click on them to bring up the image on its own page. Of the two that might cover the area, it’s CTX image G01_018494_1930_XN_13N115W that has the feature in the upper third of the image.
You can use the Flash-based zoomer, or you can use any of the browse formats to get a smaller version (though larger than the thumbnail). This CTX image has a pixel scale of about 5.5 m/px, but it looks somewhat grainy. I would guess this is due to possibly photographing through a mild dust storm, or they didn’t expose the camera long enough. However, the feature itself is clearly visible.
MOC, THEMIS, Viking, and HRSC have also all taken photos of the feature, visible through the webmap interface, all with different resolutions. THEMIS took a color image, and HRSC has an image at 12.5 m/px.
If I had to guess, it’s that the THEMIS image is what’s used in the Google Maps version shown on the UFO site, and that Google has also just colored it a rusty orange.
Investigating the Claim: Positive or Negative Relief
Various persons on the UFO page and other places that this is being reported say that it’s a positive feature, meaning that it comes out at you like a hill. Others, like on the Ghost Theory site claim that it’s also positive relief, but that the shadows have been played with in the area.
Mars Object with Context and Craters Identified
Given that we can go to numerous original images and not ones that have been mosaicked together, we can look at the shadows of other features. To be scientific, you can use the sun angles given in the data on the ASU site for each individual image. Or, you can just look at the craters. Craters are negative features, going into the surface. Shadows will be on the side facing away from the sun, while highlights will be facing the sun. Using the shadows on the craters, we can clearly see that the shadows of this feature match, and so it is a negative relief feature.
Already, that negates claims made on these sites that it’s a space ship or a big rock. Despite the claim in the article: “This structure also does not go under the ground, but instead is laying on the surface of Mars.” As will be a bit of a theme during our TAM workshop (1A!!!!), when someone says “This is NOT [something],” that should be the first thing you check on.
Investigating the Claim: What Is It? Crater?
The default for a hole in the ground on most solid solar system objects other than Earth is an impact crater. And you can get highly elliptical impact craters.
However, this does not look like an impact crater: (1) There is no raised rim, (2) there is no ejecta, (3) the walls are very steep, and (4) the floor looks flat (though no topography data is available). Taking these in order …
1. All impact craters start with a raised rim. These do erode over time, but it takes time. Looking at other craters in the same images, they all have raised rims but the floors look like they’re infilled (they’re not as deep as they should be … remember, I got my Ph.D. studying Mars’ crater population). Given that this is on a very young surface (lack of large craters), it’s very unlikely that such a rim would erode to literally nothing: The ground is flat, and then it drops down into this feature. Not an impact crater.
2. All craters eject material when they form. There is no evidence of ejecta – either present or fossilized – and again with the youth of the feature, this would be very surprising for an impact crater.
3-4. Impact craters that are small are bowl-shaped and have characteristic slopes to their walls. This looks much steeper than you’d get with an impact crater, more typical of what I’ll discus later. Similarly, all small craters are, as I said, bowl-shaped, and this lacks that bowl on the floor. This could be explained by infilling so, in itself, that’s not a reason to discount it being an impact crater. Given the other points, it’s fairly conclusive.
Investigating the Claim: What Is It? Geologic Context
This is on the massive volcanic province of Mars known as the Tharsis region, or Tharsis bulge, or just Tharsis. Massive volcanos resurfaced large parts of it as recently as about 100 million years ago — yes, if the dinosaurs had telescopes and spacecraft in orbit, they would have seen active volcanoes on Mars.
Volcanic vents are fed by lava tubes. When lave tubes are evacuated, they are hollow. You can walk through some in Hawai’i. When they’re hollow, they can collapse. Again, check out Chain of Craters Road in Hawai’i.
When they collapse, you can get individual craters (“pit craters”), or if a large portion of the tube collapses, you get graben – a linear feature with a flat floor and very steep sides – typically steeper than an impact crater. (You can get graben other ways, but this is one of them.)
Mars Object with Broad Context (click image to embiggen)
With that in mind, look elsewhere in the CTX, HRSC, or THEMIS images. You will see graben. In fact, there’s a large, long one a few 10s miles/km north of the feature in question. In fact, between that graben and this feature, there’s another one that looks similar to this feature. In fact, this feature runs parallel to other nearby graben. In fact, there is a very shallow graben leading right into the west end of this feature, in the same direction as the long axis of this feature. In fact …
Investigating the Claim: What Is It? Collapsed Lava Tube?
… that’s what this very likely is: A portion of a collapsed lava tube. It makes sense given the geologic setting. It makes sense given the orientation relative to other obvious graben in the area. It makes sense given that it’s unlikely to be an impact crater.
I think another possibility (less likely in my opinion) is that it’s a large volcanic vent – another type of crater, a “volcanic crater” (AKA caledera). The reason I think this is less likely is that I don’t see evidence of magma coming out of it – there isn’t anything radiating away. Topography data would help settle that, but given that the flows immediately north and south of it appear to continue as though it doesn’t exist, and then this feature is just right on top of them, I think it’s more likely to be the collapsed lava tube.
What It’s Not
Not a spaceship. Not a big rock. And yet, with the headline of, “Ancient Structure On Mars,” you get all sorts of commenters on the UFO website exercising their amazing powers of pareidolia:
“It even has windows along the sides! It could be a building but more likely it is a vehicle.”
“I sent an email with a photo showing what I believe are tracks, lines of holes in the sand, behind the object, (behind meaning at the fat end). It might be that wheels there are complex, not round but different from wheels on Earth, due to the soft sand. They might have deep knobs on the tires, or something like that.”
And from the original post itself: “Notice the evenness of the lines. The balance of the indents that go all the way down the sides. The back seems thinner a bit than the front…if it is the front. This structure shows lots of signs of being an a spaceship that has long since been abandoned on Mars.”
Well that was fun. Good to get the juices flowing and prolong my crappy sleep schedule.
The bottom-line here is that this appears to be a very natural, volcanic feature on Mars. To someone who’s a geologist or knows what they’re doing, anyway. I love that Google and other companies make these things available, that NASA is one of the most open space agencies in the world with releasing their image data, and that people love to pour over these images. It helps increase the interest in space exploration and you really do get cases of laypersons finding features that turn out to be major discoveries, like natural bridges on the Moon.
The downside is that this stuff also happens — people see something they don’t understand, and they leap to wild conclusions. And, with the internet, it can very quickly gain traction. An oft-quoted Mark Twain line is, “A lie can get halfway around the world before the truth can even get its boots on.”
I’m not accusing the UFO Sightings Daily website of lying. But, the quote can easily be adapted to replace “lie” with “misunderstanding” or even “paranormal claim.”
Also, as I’ve talked about before, it’s MUCH easier to spread a misunderstanding – or to have the misunderstanding – than to figure out what’s going on. I’ve spent >1800 words going through this claim. Granted, I could’ve probably cut it in half by just cutting to the chase, but it’s late and I’m being verbose and I wanted to do this logically and thoroughly explain my argument. Meanwhile, I’m sure the UFO folks are on to their next Mars pareidolia.
So why do this? Because the more people who are trained and armed with the tools to investigate stuff like this, the harder that misunderstanding is to propagate, and the faster people will be able to call them on it.