Scroll down to read this post.


In celebration of my birthday on February 5, 2023, I am running a campaign to raise money to support my work here at Behind The Black. I do not run ads. My only support comes from my readers, which leaves me utterly free to speak my mind openly about space, culture, and politics. Please consider supporting me in this work by giving either a one-time contribution or a regular subscription, in any one of the following ways:


1. Zelle: This is the only internet method that charges no fees. All you have to do is use the Zelle link at your internet bank and give my name and email address (zimmerman at nasw dot org). What you donate is what I get.


2. Donate through Gabpay, using my email address zimmerman @ nasw dot org.

3. Patreon: Go to my website there and pick one of five monthly subscription amounts, or by making a one-time donation.

4. A Paypal Donation:

4. A Paypal subscription:

5. Donate by check, payable to Robert Zimmerman and mailed to
Behind The Black
c/o Robert Zimmerman
P.O.Box 1262
Cortaro, AZ 85652

Scientists: Viking-1 might have landed on a field of Martian tsunami debris

The geological history of the Viking-1 Mars landing site

As outlined in their new paper [pdf], a team of scientists now hypothesize that the features that surrounded Viking-1 when it landed on Mars in 1976 were caused by two past Martian tsunamis. Each tsunamis occurred due to an impact in the theorized ocean that is believed to have existed in this part of Mars’ northern lowland plains several billion years ago.

The graphic to the right, figure 8 from the paper, shows the hypothesized sequence of events. From the caption:

(a) Pohl crater forms within a shallow marine environment, (b) triggering tsunami water and debris flow fronts. (c) The wave fronts extensively inundate the highland lowland boundary plains, including a section ~ 900 km southwest of the impact site. (d) The ocean regresses to ~ − 4100 m, accompanied by regional glacier dissection, which erode the rims of Pohl and other craters. (e) The younger tsunami overflows Pohl and parts of the older tsunami. Glaciation continues, and mud volcanoes later source and emerge from the younger tsunami deposit. (f) ~ 3.4 billion years later, the Viking 1 Lander touches down on the edge of the older tsunami deposit.

The overview map below provides the larger context.

Overview map

The theorized northern ocean was first proposed by this same science team in a 2019 paper. This new work gathers more of the recent data gathered by orbiters, combines it with past Viking-1 data, and uses this information to run simulations to model the consequences of two impacts during the existence of this northern ocean.

When Viking-1 landed, scientists had expected to find extensive evidence that surface water had once existed at the landing site. From the press release:

“However – and very unexpectedly – the in-situ imaged landscapes revealed boulder-strewn plains lacking recognizable fluvial features. These plains were interpreted to be the top of a boulder-rich deposit multiple meters thick,” [lead scientist Alex] Rodriguez said.

Early hypotheses suggested the landing site was on a thick blanket of debris ejected by nearby impacts or broken-up lavas. However, it was also recognized that nearby craters were too few and that lava fragments were rare. The lack of consensus persisted during the six years of operation, leading to an enduring mystery in planetary exploration. “Our investigation provides a new solution – that a tsunami washed ashore, emplacing sediments on which, about 3.4 billion years later, the Viking 1 lander touched down,” Rodriguez said.

As always, there is much uncertainty here, especially because in situ research is limited to only two sites (Viking-1 and Pathfinder). The paper however also recognizes that fundamental mystery of Mars — that so far no one has been able to convincingly model a past Martian climate that would allow liquid water on its surface — by including glacial activity in its modeling.

“We find evidence that as the ocean froze and receded, circum-oceanic glaciers developed and eroded the rim of Pohl. The glaciation appears to have been wet based, so it was probably coupled with ice-covered rivers. This is an important result because wet-based glaciation occurs during relatively “warm” climatic conditions, comparable to, say, Greenland today, or Alaska and Norway when the Ice Age ended,” said co-author Kargel of PSI.

As I have noted before in my coverage of Mars research, the science community is increasingly looking at glacial activity as a major component of past Martian geology, something that no one had considered prior to the data from recent orbiters.

(Note: For reasons that only serve to confuse, the scientists decided to call these tsunamis “megatsunamis.” These waves might have been big events, but I can see no difference in size between these and similar very large tsunamis on Earth. To add this extra size modifier that provides no real information is mere jargon, and I have edited the text above, removing it for clarity.)

Conscious Choice cover

Now available in hardback and paperback as well as ebook!


From the press release: In this ground-breaking new history of early America, historian Robert Zimmerman not only exposes the lie behind The New York Times 1619 Project that falsely claims slavery is central to the history of the United States, he also provides profound lessons about the nature of human societies, lessons important for Americans today as well as for all future settlers on Mars and elsewhere in space.

Conscious Choice: The origins of slavery in America and why it matters today and for our future in outer space, is a riveting page-turning story that documents how slavery slowly became pervasive in the southern British colonies of North America, colonies founded by a people and culture that not only did not allow slavery but in every way were hostile to the practice.  
Conscious Choice does more however. In telling the tragic history of the Virginia colony and the rise of slavery there, Zimmerman lays out the proper path for creating healthy societies in places like the Moon and Mars.


“Zimmerman’s ground-breaking history provides every future generation the basic framework for establishing new societies on other worlds. We would be wise to heed what he says.” —Robert Zubrin, founder of founder of the Mars Society.


All editions are available at Amazon, Barnes & Noble, and all book vendors, with the ebook priced at $5.99 before discount. The ebook can also be purchased direct from my ebook publisher, ebookit, in which case you don't support the big tech companies and I get a bigger cut much sooner.


Autographed printed copies are also available at discount directly from me (hardback $24.95; paperback $14.95; Shipping cost for either: $5.00). Just email me at zimmerman @ nasw dot org.


Readers: the rules for commenting!


No registration is required. I welcome all opinions, even those that strongly criticize my commentary.


However, name-calling and obscenities will not be tolerated. First time offenders who are new to the site will be warned. Second time offenders or first time offenders who have been here awhile will be suspended for a week. After that, I will ban you. Period.


Note also that first time commenters as well as any comment with more than one link will be placed in moderation for my approval. Be patient, I will get to it.

Leave a Reply

Your email address will not be published. Required fields are marked *