Read the Beforeitsnews.com story here. Advertise at Before It's News here.
Profile image
By Alton Parrish (Reporter)
Contributor profile | More stories
Story Views
Now:
Last Hour:
Last 24 Hours:
Total:

When Did The Raging Rivers of Mars Die?

% of readers think this story is Fact. Add your two cents.


Long ago on Mars, water carved deep riverbeds into the planet’s surface–but we still don’t know what kind of weather fed them. Scientists aren’t sure, because their understanding of the Martian climate billions of years ago remains incomplete.

A new study by University of Chicago scientists cataloged these rivers to conclude that significant river runoff persisted on Mars later into its history than previously thought. According to the study, published March 27 in Science Advances, the runoff was intense–rivers on Mars were wider than those on Earth today–and occurred at hundreds of locations on the red planet.

This complicates the picture for scientists trying to model the ancient Martian climate, said lead study author Edwin Kite, assistant professor of geophysical sciences and an expert in both the history of Mars and climates of other worlds. “It’s already hard to explain rivers or lakes based on the information we have,” he said. “This makes a difficult problem even more difficult.”

A photo of a preserved river channel on Mars, taken by an orbiting satellite, with color overlaid to show different elevations (blue is low, yellow is high).

Credit: NASA/JPL/Univ. Arizona/UChicago

But, he said, the constraints could be useful in winnowing the many theories researchers have proposed to explain the climate.

Mars is crisscrossed with the distinctive tracks of long-dead rivers. NASA’s spacecraft have taken photos of hundreds of these rivers from orbit, and when the Mars rover Curiosity landed in 2012, it sent back images of pebbles that were rounded–tumbled for a long time in the bottom of a river.

It’s a puzzle why ancient Mars had liquid water. Mars has an extremely thin atmosphere today, and early in the planet’s history, it was also only receiving a third of the sunlight of present-day Earth, which shouldn’t be enough heat to maintain liquid water “Indeed, even on ancient Mars, when it was wet enough for rivers some of the time, the rest of the data looks like Mars was extremely cold and dry most of the time,” Kite said.

 
Seeking a better understanding of Martian precipitation, Kite and his colleagues analyzed photographs and elevation models for more than 200 ancient Martian riverbeds spanning over a billion years. These riverbeds are a rich source of clues about the water running through them and the climate that produced it. For example, the width and steepness of the riverbeds and the size of the gravel tell scientists about the force of the water flow, and the quantity of the gravel constrains the volume of water coming through.

Their analysis shows clear evidence for persistent, strong runoff that occurred well into the last stage of the wet climate, Kite said.

The results provide guidance for those trying to reconstruct the Martian climate, Kite said. For example, the size of the rivers implies the water was flowing continuously, not just at high noon, so climate modelers need to account for a strong greenhouse effect to keep the planet warm enough for average daytime temperatures above the freezing point of water.

The rivers also show strong flow up to the last geological minute before the wet climate dries up. “You would expect them to wane gradually over time, but that’s not what we see,” Kite said. The rivers get shorter–hundreds of kilometers rather than thousands–but discharge is still strong. “The wettest day of the year is still very wet.”

It’s possible the climate had a sort of “on/off” switch, Kite speculated, which tipped back and forth between dry and wet cycles.

“Our work answers some existing questions but raises a new one. Which is wrong: the climate models, the atmosphere evolution models, or our basic understanding of inner solar system chronology?” he said

UChicago Planetary GIS/Data Specialist David Mayer, now at the United States Geologic Survey Astrogeology Program, and then-visiting student Gaia Stucky de Quay from Imperial College London, co-authored the study, as well as scientists with the Smithsonian Institution, the Natural History Museum in London and the Centre National de la Recherche Scientifique in Paris. The study used University of Chicago Research Computing Center resources.

Contacts and sources:
Louise Lerner
University of Chicago

Citation: “Persistence of intense, climate-driven runoff late in Mars history.” Kite, et al, Science Advances, March 27, 2019. Doi: 10.1126/sciadv.aav7710
 



Source:


Before It’s News® is a community of individuals who report on what’s going on around them, from all around the world.

Anyone can join.
Anyone can contribute.
Anyone can become informed about their world.

"United We Stand" Click Here To Create Your Personal Citizen Journalist Account Today, Be Sure To Invite Your Friends.

Please Help Support BeforeitsNews by trying our Natural Health Products below!


Order by Phone at 888-809-8385 or online at https://mitocopper.com

Order by Phone at 888-809-8385 or online at https://www.herbanomic.com


Get our Free Ebook, "Suppressed Health Secrets"  with  Natural Cures THEY don't want you to know!

Humic & Fulvic Trace Minerals Complex - Nature's most important supplement! Vivid Dreams again!

Ultimate Clinical Potency Curcumin - Natural pain relief, reduce inflammation and so much more.

MitoCopper - Bioavailable Copper destroys pathogens and gives you more energy. (See Blood Video)
Oxy Powder - Natural Colon Cleanser!  Cleans out toxic buildup with oxygen! 
Organic Hemp Extract (CBD) - Full Spectrum high CBD (3300mg) hemp extract eases stiff joints, relieves stress and more!
Nascent Iodine - Promotes detoxification, mental focus and thyroid health.
Smart Meter Cover -  Reduces Smart Meter radiation by 96%!  (See Video)

Immusist Beverage Concentrate - Proprietary blend, formulated to reduce inflammation while hydrating and oxygenating the cells.

Report abuse
Loading...
    Loading...

    Comments

    Your Comments
    Question   Razz  Sad   Evil  Exclaim  Smile  Redface  Biggrin  Surprised  Eek   Confused   Cool  LOL   Mad   Twisted  Rolleyes   Wink  Idea  Arrow  Neutral  Cry   Mr. Green

    MOST RECENT
    Load more ...

    SignUp

    Login

    Newsletter

    Email this story
    Email this story

    If you really want to ban this commenter, please write down the reason:

    If you really want to disable all recommended stories, click on OK button. After that, you will be redirect to your options page.