April 03, 2019
Good Morning,
Water on Mars? Well, deep groundwater actually, but water nonetheless! A new study says that the red planet may still have active groundwater below the surface. Could colonization be in our future?
Learn about this and more interesting stories from the scientific community in today's issue.
Until Next Time,
Erin
P.S. Did you miss an issue? You can read every issue from the Gophercentral library of newsletters on our exhaustive archives page. Thousands of issues, all of your favorite publications in chronological order. You can read AND comment. Just click
GopherArchives
|
*-- Evidence of deep groundwater on Mars detailed in new study --*
Mars may still host active groundwater deep beneath its surface, according to a new study by researchers at the University of Southern California.
After closely analyzing a phenomenon known as "recurrent slope linea," estimated to be the dry signatures left by short-lived streams, scientists determined deep groundwater on Mars is likely not relegated to the poles.
Researchers have previously argued surface water activity accounts for the recurrent slope linea found on the walls of Martian craters.
"We suggest that this may not be true," Essam Heggy, a scientist working on ESA's Mars Express Sounding radar experiment, called MARSIS, said in a news release. "We propose an alternative hypothesis that they originate from a deep pressurized groundwater source which comes to the surface moving upward along ground cracks."
Heggy is an expert on groundwater systems, and his observation of deep-lying groundwater in otherwise dry places, including in the North African Sahara and in the Arabian Peninsula, led him to consider the possibility that similar groundwater activity is present deep beneath the Martian surface.
Abotalib Z. Abotalib, a postdoctoral research associate at USC, examined the evidence and determined deep Martian spring water could rise through fissures in crater walls, causing recurrent slope linea. High-resolution images of Mars' surface suggest the sources of recurrent slope linea are located near tectonic and impact-related fractures.
Scientists have previously used electromagnetic echoes sent from radar-probing spacecraft orbiting Mars to search for water beneath the surface of the Red Planet. So far, such surveys have only turned up evidence of groundwater beneath Mars' southern pole.
Heggy and Abotalib hypothesize that a deeper and more extensive groundwater systems stretches far beyond Mars' south pole. The duo detailed their hypothesis in a paper published Thursday in the journal Nature Geoscience.
The authors of the new paper hope their findings inspire ESA, NASA and other space agencies to develop technologies capable of exploring deep Martian fissures and detecting deep-lying water.
As scientists have gained a better and better understanding of Mars, a growing body of evidence suggests Earth and the Red Planet are more similar than previously thought. By understanding Mars' groundwater system and its evolutionary history, scientists can gain a better understanding of Earth's past and future.
"It helps us to understand the similarities to our own planet and if we are going through the same climate evolution and the same path that Mars is going," Heggy said. "Understanding Mars' evolution is crucial for understanding our own Earth's long-term evolution and groundwater is a key element in this process."
*-- Tiny Brazilian frogs glow in the dark -- under a UV lamp --*
While studying the mating calls of pumpkin toadlets in the Brazilian rainforest, biologists realized the tiny frogs were deaf to their own songs. Further investigation revealed an alternate mode of communication, glow-in-the-dark bones.
When scientists studied the miniature Brazilian frogs under an ultra-violet lamp, they found glowing patterns across the heads and backs of the tiny reptiles.
"The fluorescent patterns are only visible to the human eye under a UV lamp," Sandra Goutte, an evolutionary biologist and researcher at New York University Abu Dhabi, said in a news release. "In nature, if they were visible to other animals, they could be used as intra-specific communication signals or as reinforcement of their aposematic coloration, warning potential predators of their toxicity."
Back in the lab, Goutte and her colleagues compared the skeletons of pumpkin toadlets to the skeletons of related, non-fluorescent species. The bones of the pumpkin toadlets glowed under the UV lamp.
Pumpkin toadlets are active during the daytime. Scientists estimate sunlight's UV or near-UV wavelengths are sufficient to illuminate fluorescent patterns detectable by some species.
Researchers identified fluorescent dermal bones in the head and back of two pumpkin toad species, Brachycephalus ephippium and B. pitanga. They described their discovery in the journal Scientific Reports.
Scientists aren't yet sure whether the fluorescent patterns are used for intraspecies communication, to ward off specific predators or both.
"More research on the behavior of these frogs and their predators is needed to pinpoint the potential function of this unique luminescence," Goutte said.
|