Image of a channel between putative lakes from the Context Camera (CTX) onboard NASA's Mars Reconnaissance Orbiter (MRO).

New Images Suggest More Recent Lakes on Mars

5 Jan , 2010 by

Image of a channel between putative lakes from the Context Camera (CTX) onboard NASA’s Mars Reconnaissance Orbiter (MRO).

Modern Mars is frigid and dry, but new evidence suggests that in some locations on the equator there may have been lakes as recently as 3 billion years ago.

Researchers from Imperial College London and University College London studied images from the context camera (CTX) on NASA’s Mars Reconnaissance Orbiter (MRO) of several flat-floored depressions in Ares Vallis, near the martian equator.

Previously these depressions were thought to be due to the collapse of the surface as ground ice sublimated directly to gas, but CTX images reveal small channels connecting the depressions, suggesting that water flowed between them. Similar features can be found in “thermokarst” landscapes in Alaska and elsewhere, where permafrost is melting to create lakes and streams.

To determine the age of the features, the scientists counted more than 35,000 craters in the area. Assuming that the current surface was continuously exposed to impacts from space since it was emplaced, the density of craters points to an age of roughly three billion years.

Previously, it was thought that Mars dried up between 4 and 3.8 billion years ago, but if the cratering age from this study is correct, these new results suggest at least brief periods later in martian history when lakes could exist.

The lead author, Dr Nicholas Warner, from the Department of Earth Science and Engineering at Imperial College London, said: “Most of the research on Mars has focused on its early history and the recent past. Scientists had largely overlooked the Hesperian Epoch as it was thought that Mars was then a frozen wasteland. Excitingly, our study now shows that this middle period in Mars’ history was much more dynamic than we previously thought.”

It is not clear how long-lived the lakes were, but Warner and colleagues suggest that they may have served as oases for life in an otherwise inhospitable world. They also suggest that these lakes would be an interesting landing site for future robotic missions.

What’s the next step? The researchers plan to study other equatorial areas, including the mouth of Ares Vallis and Chryse Planitia to see how widespread the putative lakes were.

, ,



Sort by:   newest | oldest | most voted
Torbjorn Larsson OM
Member
Torbjorn Larsson OM
January 5, 2010 7:22 AM
So, um, do these potentially “long-lived” lakes and perhaps open flowing waters have implications for atmospheric models? I assume the Hesperian epoch would remain, as it is “marked by the formation of extensive lava plains” and the Noachian is defined (?) by “many large impact craters” [Wikipedia]. The mineralogical Siderikan epoch may or may not move over a bit, from 3.5 Ga to 3, depending on atmosphere conditions. (“With the end of volcanism and the absence of liquid water, the most notable geological process has been the oxidation of the iron-rich rocks … “.) But if there were life, if only dragged up into ice-covered waters that remained under low pressure by dust covers as ice persist over… Read more »
Aqua4U
Member
January 5, 2010 11:12 AM

Eventually I think we will find that during the most extreme planetary dust storms on Mars, suspended particles act as abrasive elements causing continued erosion on the surface. The suspended particulates, in a fluidic state, then RESEMBLES water erosion.

Alternately, we might find that during planetary dust storms, surface temperatures rise high enough for liquid water (albeit salt saturated) to form and ALSO cause some of the observed erosion.

Planetary dust storms occur during Mars closest approach to Sol and may also occur due to volcanic eruption, meteor impact or even tribo electric bombardment associated with CME’s. Should it be that some or all of these factors coincide, then how high might surface temperatures go?

Aqua4U
Member
January 5, 2010 11:27 AM

Another factor to consider would be Mars polar inclination shifting as it processes through ‘recent’ geologic time.

Aqua4U
Member
January 5, 2010 3:07 PM
Torbjorn Larsson OM Try: Topic C in this abstract: http://www.case.edu/cse/eche/ESA2008_Proceedings/F2.pdf Or: http://www.iop.org/EJ/article/1367-2630/5/1/370/nj3170.html Or: http://physics.ksc.nasa.gov/Publications/Results%20of%20Mission-Ready%20Triboelectric%20Device-Final.pdf (This for a device to determine charge state on the Martian surface) Or: http://www.lpi.usra.edu/meetings/7thmars2007/pdf/3122.pdf Given the extremely low temperatures, pressures and atmospheric moisture content combined with dust particle size and lower gravity, tribo electric forces may play a far greater role in Martian weather than has been previously assumed? Your statement, “under general conditions abrasion tends to flatten out topography” – Consider what fluids/water does to earthly terrains. Yes there are flattened areas where water has pooled AND then there are places like the Grand Canyon, where obviously gravity and elevation plays a role in the effects of abrasive fluids. The transference of electrical… Read more »
Torbjorn Larsson OM
Member
Torbjorn Larsson OM
January 5, 2010 12:48 PM
Aqua, I’m disappointed, you don’t live up to your name. But we can test your dusty hypothesis. Meridiani Planum, that Opportunity travels on, has been so scoured by abrasion to loose some ~ 1 km of material, or so Wikipedia claims. Does it look like fluvial features? No, it is flat. Not surprisingly, as under general conditions abrasion tends to flatten out topography. [Funny how friction ‘dissipates’ entropy from macroscale to microscale, always.] Dust abrasion fails a test. But we need to be fair and test the water hypothesis too. We now know that water has been influential in forming Mars, both from spectroscopic analysis of minerals from orbit and from direct finds from Opportunity, Spirit and Phoenix.… Read more »
Olaf
Member
Olaf
January 5, 2010 12:48 PM

Aqua, I have no idea what you are talking about. Nothing makes sense in your scientific explanation.

Smells like pseudoscience.

Aqua4U
Member
January 7, 2010 1:24 PM

Oops.. I forgot CO2

wpDiscuz