Mars
New Study Challenges Long-Held Theory of Fate of Mars’ Water
Grey Hautaluoma / Alana Johnson
NASA Headquarters, Washington
grey.hautaluoma-1@nasa.gov / alana.r.johnson@nasa.gov
Andrew Good
Jet Propulsion Laboratory, Pasadena, Calif.
andrew.c.good@jpl.nasa.gov
This global view of Mars is composed of about 100 Viking Orbiter images. Credit: NASA/JPL-Caltech/USGS
The new science results indicate that a large quantity of the Red Planet’s water is trapped in its crust rather than having escaped into space.
Billions of years ago, according to geological evidence, abundant water flowed across Mars and collected into pools, lakes, and deep oceans. New NASA-funded research shows a substantial quantity of its water – between 30 and 99% – is trapped within minerals in the planet’s crust, challenging the current theory that due to the Red Planet’s low gravity, its water escaped into space.
Early Mars was thought to have enough water to have covered the whole planet in an ocean roughly 100 to 1,500 meters (330 to 4,920 feet) deep – a volume roughly equivalent to half of Earth’s Atlantic Ocean. While some of this water undeniably disappeared from Mars via atmospheric escape, the new findings, published in the latest issue of Science, conclude it does not account for most of its water loss.
Read the rest of this entry »What’s Up – October 2019
Published by NASA
Link to article with video: https://www.jpl.nasa.gov/video/details.php?id=1588
Link to page: International Observe the Moon Night, Oct 5, 2019
What can you see in the October sky? Join the global celebration of International Observe the Moon Night on Oct. 5th, then try to catch the ice giant planets Uranus and Neptune, which are well placed for viewing in the late night sky.
Transcript:
What’s Up for October? A night for the whole world to observe the Moon and hunting for ice giants!
International Observe the Moon Night is Oct. 5th. It’s an annual celebration of lunar observation and exploration. Events are scheduled in lots of places around the world, so there may be one near you. But all you really need to participate is to go out and look up.
The event is timed to coincide with the first quarter moon. This allows for some great observing along the lunar terminator – the line that divides the dayside from the nightside. With even a small pair of binoculars, you can see some great details as features like mountains and craters pop up into the light. Learn more and look for events in your area at moon.nasa.gov/observe.
October is a great time to try and capture an ICE GIANT. Now, these aren’t mythical creatures. They’re planets – the most distant of the major planets of our solar system, Uranus and Neptune.
The four giant planets of our solar system are not created equal. The gas giants, Jupiter and Saturn, are much bigger and way more massive, while the ice giants are so named because they contain a much higher amount of materials that typically form ices in the frigid depths of the outer solar system.
In October, both Uranus and Neptune are well placed in the late night sky. In fact, you can see all four giant planets in the same evening if you look for Jupiter and Saturn in the west after sunset, and then come back a couple of hours later to spot Uranus and Neptune. (Think of it as your own personal “Voyager mission.” NASA’s Voyager 2 is the only spacecraft to have visited the ice giants so far, although scientists are eager to go back for a more detailed study.)
Unlike Jupiter and Saturn, the ice giants are quite faint, so the best way to observe them is with a telescope, and from personal experience, it’s much easier to find them if you have a computer-controlled mount that can automatically point the telescope for you. If you don’t have access to one, find a local event with the Night Sky Network at nightsky.jpl.nasa.gov. Otherwise, sky watching apps can help you star-hop your way to these two incredibly distant planets.
Now be advised, because they’re so far away, each planet appears as just a point of light. But with a modest telescope, you’ll see Uranus as a tiny disk. You’d be forgiven for mistaking Neptune as a star – it’s the same size as Uranus, but much farther away, so it’s fainter.
The ice giants are elusive, but well worth the effort to say you’ve seen them with your own eyes.
Here are the phases of the Moon for October. You can catch up on all of NASA’s current and future missions at nasa.gov. I’m Preston Dyches from NASA’s Jet Propulsion Laboratory, and that’s What’s Up for this month.
NASA’s InSight ‘Hears’ Peculiar Sounds on Mars
Andrew Good
Jet Propulsion Laboratory, Pasadena, Calif.
andrew.c.good@jpl.nasa.gov
Alana Johnson
NASA Headquarters, Washington
alana.r.johnson@nasa.gov
Put an ear to the ground on Mars and you’ll be rewarded with a symphony of sounds. Granted, you’ll need superhuman hearing, but NASA’s InSight lander comes equipped with a very special “ear.”
The spacecraft’s exquisitely sensitive seismometer, called the Seismic Experiment for Interior Structure (SEIS), can pick up vibrations as subtle as a breeze. The instrument was provided by the French space agency, Centre National d’Études Spatiales (CNES), and its partners.
Mar’s Solar Conjuction — What Is It & What It Means
Andrew Good
Jet Propulsion Laboratory, Pasadena, Calif.
andrew.c.good@jpl.nasa.gov
Alana Johnson
NASA Headquarters, Washington
alana.r.johnson@nasa.gov
The daily chatter between antennas here on Earth and those on NASA spacecraft at Mars is about to get much quieter for a few weeks.
That’s because Mars and Earth will be on opposite sides of the Sun, a period known as Mars solar conjunction. The Sun expels hot, ionized gas from its corona, which extends far into space. During solar conjunction, this gas can interfere with radio signals when engineers try to communicate with spacecraft at Mars, corrupting commands and resulting in unexpected behavior from our deep space explorers.
For InSight, Dust Cleanings Will Yield New Science
Andrew Good
Jet Propulsion Laboratory, Pasadena, Calif.
andrew.c.good@jpl.nasa.gov
The same winds that blanket Mars with dust can also blow that dust away. Catastrophic dust storms have the potential to end a mission, as with NASA’s Opportunity rover. But far more often, passing winds cleared off the rover’s solar panels and gave it an energy boost. Those dust clearings allowed Opportunity and its sister rover, Spirit, to survive for years beyond their 90-day expiration dates.
Dust clearings are also expected for Mars’ newest inhabitant, the InSight lander. Because of the spacecraft’s weather sensors, each clearing can provide crucial science data on these events, as well – and the mission already has a glimpse at that.
The Mars InSight Landing Site Is Just Plain Perfect
No doubt about it, NASA explores some of the most awe-inspiring locations in our solar system and beyond. Once seen, who can forget the majesty of astronaut Jim Irwin standing before the stark beauty of the Moon’s Hadley Apennine mountain range, of the Hubble Space Telescope’s gorgeous “Pillars of Creation” or Cassini’s magnificent mosaic of Saturn?
Mars also plays a part in this visually compelling equation, with the high-definition imagery from the Curiosity rover of the ridges and rounded buttes at the base of Mount Sharp bringing to mind the majesty of the American Southwest. That said, Elysium Planitia – the site chosen for the Nov. 26 landing of NASA’s InSight mission to Mars – will more than likely never be mentioned with those above because it is, well, plain.
Mar’s Volcanoes and Earth’s Dinosaurs Went Extinct Same Time
Elizabeth Zubritsky
Jacob Bleacher
Jacob Richardson
Goddard Space Flight Center, Greenbelt, Md.
New NASA research reveals that the giant Martian volcano Arsia Mons produced one new lava flow at its summit every 1 to 3 million years during the final peak of activity. The last volcanic activity there ceased about 50 million years ago — around the time of Earth’s Cretaceous-Paleogene extinction, when large numbers of our planet’s plant and animal species (including dinosaurs) went extinct.
Located just south of Mars’ equator, Arsia Mons is the southernmost member of a trio of broad, gently sloping shield volcanoes collectively known as Tharsis Montes. Arsia Mons was built up over billions of years, though the details of its lifecycle are still being worked out. The most recent volcanic activity is thought to have taken place in the caldera-the bowl-shaped depression at the top — where 29 volcanic vents have been identified. Until now, it’s been difficult to make a precise estimate of when this volcanic field was active.
NASA Awards Launch Services Contract for Mars 2020 Rover Mission
NASA has selected United Launch Services LLC of Centennial, Colorado, to provide launch services for a mission that will address high-priority science goals for the agency’s Journey to Mars.
Mars 2020 is targeted for launch in July 2020 aboard an Atlas V 541 rocket from Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. The rover will conduct geological assessments of its landing site on Mars, determine the habitability of the environment, search for signs of ancient Martian life, and assess natural resources and hazards for future human explorers.
Test for Damp Ground at Mars Streaks Finds None
Seasonal dark streaks on Mars that have become one of the hottest topics in interplanetary research don’t hold much water, according to the latest findings from a NASA spacecraft orbiting Mars.
The new results from NASA’s Mars Odyssey mission rely on ground temperature, measured by infrared imaging using the spacecraft’s Thermal Emission Imaging System (THEMIS). They do not contradict last year’s identification of hydrated salt at these flows, which since their 2011 discovery have been regarded as possible markers for the presence of liquid water on modern Mars. However, the temperature measurements now identify an upper limit on how much water is present at these darkened streaks: about as much as in the driest desert sands on Earth.
When water is present in the spaces between particles of soil or grains of sand, it affects how quickly a patch of ground heats up during the day and cools off at night.
“We used a very sensitive technique to quantify the amount of water associated with these features,” said Christopher Edwards of Northern Arizona University, Flagstaff. “The results are consistent with no moisture at all and set an upper limit at three percent water.”
The features, called recurring slope lineae or RSL, have been identified at dozens of sites on Mars. A darkening of the ground extends downhill in fingerlike flows during spring or summer, fades away in fall and winter, then repeats the pattern in another year at the same location. The process that causes the streaks to appear is still a puzzle.
“Some type of water-related activity at the uphill end still might be a factor in triggering RSL, but the darkness of the ground is not associated with large amounts of water, either liquid or frozen,” Edwards said. “Totally dry mechanisms for explaining RSL should not be ruled out.”
He and Sylvain Piqueux of NASA’s Jet Propulsion Laboratory, Pasadena, California, analyzed several years of THEMIS infrared observations of a crater-wall region within the large Valles Marineris canyon system on Mars. Numerous RSL features sit close together in some parts of the study region. Edwards and Piqueux compared nighttime temperatures of patches of ground averaging about 44 percent RSL features, in the area, to temperatures of nearby slopes with no RSL. They found no detectable difference, even during seasons when RSL were actively growing.
The report of these findings by Edwards and Piqueux has been accepted by the peer-reviewed Geophysical Research Letters and is available online.
There is some margin of error in assessing ground temperatures with the multiple THEMIS observations used in this study, enough to leave the possibility that the RSL sites differed undetectably from non-RSL sites by as much as 1.8 degrees Fahrenheit (1 Celsius degree). The researchers used that largest possible difference to calculate the maximum possible amount of water — either liquid or frozen — in the surface material.
How deeply moisture reaches beneath the surface, as well as the amount of water present right at the surface, affects how quickly the surface loses heat. The new study calculates that if RSL have only a wafer-thin layer of water-containing soil, that layer contains no more than about an ounce of water per two pounds of soil (3 grams water per kilogram of soil). That is about the same concentration of water as in the surface material of the Atacama Desert and Antarctic Dry Valleys, the driest places on Earth. If the water-containing layer at RSL is thicker, the amount of water per pound or kilogram of soil would need to be even less, to stay consistent with the temperature measurements.
Research published last year identified hydrated salts in the surface composition of RSL sites, with an increase during the season when streaks are active. Hydrated salts hold water molecules affecting the crystalline structure of the salt.
“Our findings are consistent with the presence of hydrated salts, because you can have hydrated salt without having enough for the water to start filling pore spaces between particles,” Edwards said. “Salts can become hydrated by pulling water vapor from the atmosphere, with no need for an underground source of the water.”
“Through additional data and studies, we are learning more about these puzzling seasonal features — narrowing the range of possible explanations,” said Michael Meyer. “It just shows us that we still have much to learn about Mars and its potential as a habitat for life.”
The new study touches on additional factors that add to understanding of RSL.
— If RSL were seasonal flows of briny water followed by evaporation, annual buildup of crust-forming salt should affect temperature properties. So the lack of a temperature difference between RSL and non-RSL sites is evidence against evaporating brines.
— Lack of a temperature difference is also evidence against RSL being cascades of dry material with different thermal properties than the pre-existing slope material, such as would be the case with annual avalanching of powdery dust that accumulates from dusty air.
Arizona State University, Tempe, provided and operates the THEMIS camera, which records observations in both infrared and visible-light wavelengths. JPL, a division of Caltech, manages the Mars Odyssey project for NASA. Lockheed Martin Space Systems, Denver, built the orbiter and collaborates with JPL to operate it.
Popular Science: 400-Foot High Tsunami Waves Ravaged Ancient Mars
Over three billion years ago, Mars had water. A lot more water than it has now.
Oceans of water, in fact. In a study published in Scientific Reports today, researchers found evidence of two large tsunami deposits on Mars, probably caused by large meteorites slamming into the early Martian ocean.
In addition to a massive wave of water, tsunamis carry along huge amounts of debris, some of which can be swept inland and left far beyond the shorelines. In this case, the waves created by the impacts were likely almost 400 feet high, and travelled hundreds of miles inland, carrying debris and scarring the landscape.
The two tsunamis on Mars likely occurred about 3 million years apart, enough time for the Martian climate to cool considerably. During the icy conditions of the second tsunami, large chunks of ice were likely pushed along, carried away from the ocean and left on the dry, cold surface. Researchers hope that eventually, those deposits could be examined for signs of whether the waters of Mars once had life.
To read the rest of this article, please visit Popular Science: 400-Foot High Tsunami Waves Ravaged Ancient Mars
Cosmology & Space Research Institute 
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