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New Evidence Asserts Mars Environment Over Billions of Years Ago Was Able to Support Liquid Water

River deposits exist across Mars and a region of Mars named Aeolis Dorsa contains some of the most spectacular and densely packed river deposits seen on the Red Planet

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FILE - The base of Mars' Mount Sharp is pictured in this August 27, 2012 NASA handout photo taken by the Curiosity rover. VOA

New York, September 19, 2017 : The Mars environment over 3.5 billion years ago was able to support liquid water at the surface, says a study.

River deposits exist across the surface of Mars and a region of Mars named Aeolis Dorsa contains some of the most spectacular and densely packed river deposits seen on the Red Planet, according to the study published in the Geological Society of America (GSA) Bulletin.

These deposits are observable with satellite images because they have undergone a process called “topographic inversion” where the deposits filling once topographically low river channels have been exhumed in such a way that they now exist as ridges at the surface of the planet, the researchers said.

ALSO READ NASA Scientists Reveal New Information on Mars’ Formation and Evolution, Claim The Red Planet has a Porous Crust

With the use of high-resolution images and topographic data from cameras on orbiting satellites, Benjamin T Cardenas and colleagues from Jackson School of Geosciences at the University of Texas at Austin, identified fluvial deposit stacking patterns and changes in sedimentation styles controlled by a migratory coastline.

They also developed a method to measure river paleo-transport direction for a subset of these ridges.

Together, these measurements demonstrated that the studied river deposits once filled incised valleys.

On Earth, incised valleys are commonly cut and filled during falling and rising eustatic sea level, respectively.

The researchers concluded that similar falling and rising water levels in a large water body forced the formation of the paleo-valleys in their study area.

“We present evidence that some of these fluvial deposits represent incised valleys carved and filled during falls and rises in base level, which were likely controlled by changes in water-surface elevation of a large lake or sea,” the study said.

They observed cross-cutting relationships at the valley-scale, indicating multiple episodes of water level fall and rise, each well over 50 metres, a similar scale to eustatic sea level changes on Earth. (IANS)

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NASA’S Mars Odyssey Spacecraft Captures First Images of the Martian Moon Phobos after 16 years

Phobos has an oblong shape with an average diameter of about 22 kilometres

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On September 29, Phobos was observed by Thermal Emission Imaging System (THEMIS) camera on Mars Odyssey orbiter, which has been launched in 2001. Pixabay

Washington, October 8, 2017 : After orbiting the Red Planet for 16 years, NASA’s Mars Odyssey spacecraft has captured its first images of the Martian moon Phobos.

The Thermal Emission Imaging System (THEMIS) camera on Mars Odyssey orbiter, launched in 2001, observed Phobos on September 29.

Phobos has an oblong shape with an average diameter of about 22 kilometres.

Cameras on other Mars orbiters have previously taken higher-resolution images of Phobos, but none with the infrared information available from THEMIS.

Observations in multiple bands of thermal-infrared wavelengths can yield information about the mineral composition of the surface, as well as the surface texture, NASA said in a statement this week.

“Although THEMIS has been at Mars for 16 years, this was the first time we have been able to turn the spacecraft around to look at Phobos,” said THEMIS Mission Planner Jonathon Hill of Arizona State University.

The researchers combined visible-wavelength and infrared data to produce an image color-coded for surface temperatures of this moon, which has been considered for a potential future human-mission outpost, NASA said.

“This half-moon view of Phobos was chosen because it allowed us to observe a wide range of temperatures on the surface,” Hill added.

ALSO READ NASA Scientists Reveal New Information on Mars’ Formation and Evolution, Claim The Red Planet has a Porous Crust

One major question about Phobos and Mars’ even smaller moon, Deimos, is whether they are captured asteroids or bits of Mars knocked into the sky by impact.

The researchers believe that compositional information from THEMIS might help pin down their origin.

Since Odyssey began orbiting the Red Planet in 2001, THEMIS has provided compositional and thermal properties information from all over Mars, but never before imaged either Martian moon.

The September 29 observation was completed to validate that the spacecraft could safely do so, as the start of a possible series of observations of Phobos and Deimos in coming months.

“There is heightened interest in Phobos because of the possibility that future astronauts could perhaps use it as an outpost,” said Odyssey Project Scientist Jeffrey Plaut of NASA’s Jet Propulsion Laboratory in Pasadena, California. (IANS)

 

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NASA Scientists Reveal New Information on Mars’ Formation and Evolution, Claim The Red Planet has a Porous Crust

NASA scientists claim the new revelations could help them better understand the interior structure and evolution of Mars

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Access Mars
Google collaborated with NASA to produce Access Mars that lets users wander the actual dunes and valleys explored by NASA's Curiosity rover.. Wikimedia

Washington, Septemeber 15, 2017 : Mars’s crust is not as dense as previously thought and a lower density likely means that at least part of the Red Planet’s crust is relatively porous, says a new NASA study.

The findings, published in the journal Geophysical Research Letters, provide researchers clue that could help them better understand the interior structure and evolution of Mars.

“The crust is the end-result of everything that happened during a planet’s history, so a lower density could have important implications about Mars’s formation and evolution,” said study lead author Sander Goossens of NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

The researchers mapped the density of the Martian crust, estimating the average density is 2,582 kgs per metre cubed. That’s comparable to the average density of the lunar crust.

Typically, Mars’s crust has been considered at least as dense as Earth’s oceanic crust, which is about 2,900 kgs per metre cubed.

The new value is derived from Mars’s gravity field, a global model that can be extracted from satellite tracking data using sophisticated mathematical tools.

Previous estimates relied more heavily on studies of the composition of Mars’s soil and rocks.

ALSO READ NASA Mars rover to Study an ancient fluid-carved valley incised on the inner slope of a vast crater’s r

“As this story comes together, we’re coming to the conclusion that it’s not enough just to know the composition of the rocks,” study co-author Greg Neumann, a planetary geologist at Goddard, said.

“We also need to know how the rocks have been reworked over time,” Neumann said.

Goossens and colleagues started with the same data used for an existing gravity model but put a new twist on it by coming up with a different constraint and applying it to obtain the new solution.

A constraint compensates for the fact that even the best data sets can’t capture every last detail.

Instead of taking the standard approach, known to those in the field as the Kaula constraint, the team created a constraint that considers the accurate measurements of Mars’s elevation changes, or topography.

“With this approach, we were able to squeeze out more information about the gravity field from the existing data sets,” said Goddard geophysicist Terence Sabaka.  (IANS)

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Researchers in UK hoping to Root out Modern-Day Slavery in Northern India through Satellite Images

A team of geospatial experts at the University of Nottingham use Google Maps and dozens of volunteers to identify potential sites of exploitation and report them to authorities

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FILE - A laborer carries bricks at a kiln in Karjat, India, March 10, 2016. VOA

Researchers in England are hoping to help root out modern-day slavery in northern India by using detailed satellite imagery to locate brick kilns — sites that are notorious for using millions of slaves, including children.

A team of geospatial experts at the University of Nottingham use Google Maps and dozens of volunteers to identify potential sites of exploitation and report them to authorities.

“The key thing at the moment is to get those statistics right and to get the locations of the brick kilns sorted,” said Doreen Boyd, a co-researcher on the “Slavery from Space” project.

“There are certainly activists on the ground that will help us in terms of getting the statistics and the locations of these brick kilns to [government] officials.”

Anti-slavery activists said the project could be useful in identifying remote kilns or mines that would otherwise escape public or official scrutiny.

“But there are other, more pressing challenges like tackling problematic practices, including withheld wages, lack of transparent accounting … no enforcement of existing labor laws,” said Jakub Sobik, spokesman at Anti-Slavery, a London-based nongovernmental organization.

Millions of people in India are believed to be living in slavery. Despite a 1976 ban on bonded labor, the practice remains widespread at brick kilns, rice mills and brothels, among others.

The majority of victims belong to low-income families or marginalized castes like the Dalits or “untouchables.”

Nearly 70 percent of brick kiln workers in South Asia are estimated to be working in bonded and forced labor, according to a 2016 report by the International Labor Organization. About a fifth of those are underage.

The project relies on crowdsourcing, a process where volunteers sift through thousands of satellite images to identify possible locations of kilns. Each image is shown to multiple volunteers, who mark kilns independently.

The team is currently focused on an area of 2,600 square kilometers in the desert state of Rajasthan — teeming with brick-making sites — and plans to scale up the project in the coming years.

Researchers are now in talks with satellite companies to get access to more detailed images, rather than having to rely on publicly available Google Maps.

The project is one of several anti-slavery initiatives run by the university, which include research on slave labor-free supply chains and human trafficking. (VOA)