Tagus Valles on Mars. Credit: ESA/DLR/FU Berlin (G. Neukum)
Don’t let the dry appearance of the Martian desert region near Tagus Valles fool you. Some pictures snapped by the European Space Agency’s Mars Express shows there was plenty of water in that area of the Red Planet in the past. The pictures show yet another example of how water once shaped the planet, as scientists try to figure out when and how it disappeared.
“This region is one of many that exposes evidence of the Red Planet’s active past, and shows that the marks of water are engraved in even the most unlikely ancient crater-strewn fields,” ESA stated.
The unnamed region, which is just a few degrees south of the Martian equator, partially caught scientists’ attention because of that crater you see in the top left of the image. (A closer view is below.)
Deformation in a crater that was once flooded on Mars. Credit: ESA/DLR/FU Berlin (G. Neukum)
“Numerous landslides have occurred within this crater, perhaps facilitated by the presence of water weakening the crater walls,” ESA stated. “Grooves etched into the crater’s inner walls mark the paths of tumbling rocks, while larger piles of material have slumped en masse to litter the crater floor.”
Scientists saw evidence of mesas (flat-topped blocks) and yardangs, which were both features that were built from sediments that a regional flood once deposited there. The lighter bits have eroded away, but you can still see the leftovers.
There also is evidence of volcanic activity, as there was ash scattered around the area. Scientists guess the origin was the Elysium volcanic region to the northeast.
This image shows 20 of the quenched galaxies — galaxies that are no longer forming stars — seen in the Hubble COSMOS observations. Each galaxy is identified by a crosshair at the centre of each frame. Quenched galaxies in the distant Universe are much smaller than those seen nearby. It was thought that these small galaxies merged with other smaller, gas-free galaxies to grow bigger, but it turns out that larger galaxies were "switching off" at later times and adding their numbers to those of their smaller and older siblings, giving the mistaken impression of individual galaxy growth over time. Credit: NASA, ESA, M. Carollo (ETH Zurich)
Are you ready for a new galactic puzzle? Then let’s start with some clues. It has been long assumed that some galaxies reach a point in their evolution when star formation stops. In the distant past, these saturated galaxies appeared smaller than those formed more recently. This is what baffles astronomers. Why do some galaxies continue to grow if they are no longer forming stars? Thanks to some very astute Hubble Space Telescope observations, a team of astronomers has found what appears to be a rather simple explanation. Which came first? The chicken or the egg?
Until now, these diminutive, turned-off galaxies were theorized to continue to grow into the more massive, saturated galaxies observed closer to us. Because they no longer have active star-forming regions, it was assumed they gained their extra mass by combining with other smaller galaxies – ones five to ten times less in overall size. However, for this theory to be plausible, it would take a host of small galaxies to be present for the saturated population to consume… and it’s just not happening. Because we simply did not have the data available about such a large number of galaxies, it was impossible to count and identify potential candidates, but the Hubble COSMOS survey has provided an eight billion year look at the cosmic history of turned-off galaxies.
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“The apparent puffing up of quenched galaxies has been one of the biggest puzzles about galaxy evolution for many years,” says Marcella Carollo of ETH Zurich, Switzerland, lead author on a new paper exploring these galaxies. “No single collection of images has been large enough to enable us to study very large numbers of galaxies in exactly the same way — until Hubble’s COSMOS,” adds co-author Nick Scoville of Caltech, USA.
According to the news release, the team utilized a large set of COSMOS images – the product of close to a 1,000 hours of observations and consisting of 575 over-lapped images taken with the Advanced Camera for Surveys (ACS) . Needless to say, it was one of the most ambitious projects ever undertaken by Hubble. The HST data was combined with additional observations from Canada-France-Hawaii Telescope and the Subaru Telescope to look back to when the Universe was about half its present age. This huge data set covered an area of sky almost nine times the size of the full Moon! The saturated – or “quenched” – galaxies present at that age were small and compact… and apparently remained in that state. Instead of getting larger as they evolved, they kept their small size – apparently the same size they were when star-formation ceased. Yet, these galaxy types appear to be gaining in girth as time passes. What gives?
“We found that a large number of the bigger galaxies instead switch off at later times, joining their smaller quenched siblings and giving the mistaken impression of individual galaxy growth over time,” says co-author Simon Lilly, also of ETH Zurich. “It’s like saying that the increase in the average apartment size in a city is not due to the addition of new rooms to old buildings, but rather to the construction of new, larger apartments,” adds co-author Alvio Renzini of INAF Padua Observatory, Italy.
If eight billion years teaches us anything, it teaches us that we don’t know everything…. and sometimes the most simple of answers could be the correct one. We knew that actively star-forming galaxies were far less massive in the early Universe and that explains why they were smaller when star-formation turned off.
“COSMOS provided us with simply the best set of observations for this sort of work — it lets us study very large numbers of galaxies in exactly the same way, which hasn’t been possible before,” adds co-author Peter Capak, also of Caltech. “Our study offers a surprisingly simple and obvious explanation to this puzzle. Whenever we see simplicity in nature amidst apparent complexity, it’s very satisfying,” concludes Carollo.
Fishing Boats Meet the Milky Way on the Isle of Wight (south of England) on May 16, 2013. Credit and copyright: Chad Powell.
We’ve shared many images of the Milky Way in our featured photos from astrophotographers, but this might be one of the most vibrant I’ve seen! The blue of the sky and sea is incredible and almost pulsates with its stunning azure color. Photographer Chad Powell explained on Flickr: “Where I live on the Isle of Wight (south of England) is known to have minimal light pollution but I only ever shot the Milky Way from my back garden. I decided to finally trek it down to my local beach. The Milky Way was so bright in the sky, it was breathtaking! The lights on the left are from fishing boats tens of miles out to sea.”
Simply beautiful, especially if you are a blue-o-file like I am!
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Dramatic plumes, both large and small, spray water ice out from many locations along the famed "tiger stripes" near the south pole of Saturn's moon Enceladus. Credit: NASA/JPL/SSI.
The geyser jets of Enceladus don’t shoot out in a continuous stream, but are more like an adjustable garden hose nozzle, says Cassini scientist Matt Hedman, author of a new paper about the inner workings of this fascinating tiger-striped moon. Observations from Cassini has found that the bright plume emanating from Enceladus’ south pole varies predictably. The fluctuating factor appears to be how far or close Enceladus is to its home planet, Saturn.
Scientists have hypothesized that the intensity of the jets likely varied over time, but until now had not been able to show they changed in a recognizable pattern. Hedman and colleagues were able to see the changes by examining infrared data of the plume as a whole, obtained by Cassini’s visual and infrared mapping spectrometer (VIMS), and looking at data gathered since 2004 when Cassini entered Saturn’s orbit. In 2005, the jets that form the plumes were discovered.
“The way the jets react so responsively to changing stresses on Enceladus suggests they have their origins in a large body of liquid water,” said Christophe Sotin, a co-author and Cassini team member. “Liquid water was key to the development of life on Earth, so these discoveries whet the appetite to know whether life exists everywhere water is present.”
This set of images from NASA’s Cassini mission shows how the gravitational pull of Saturn affects the amount of spray coming from jets at the active moon Enceladus. Enceladus has the most spray when it is farthest away from Saturn in its orbit (inset image on the left) and the least spray when it is closest to Saturn (inset image on the right). Credit: NASA/JPL-Caltech/University of Arizona/Cornell/SSI.
The scientists say this new finding adds to evidence that a liquid water reservoir or ocean lurks under the icy surface of the moon. This is the first clear observation the bright plume emanating from Enceladus’ south pole varies predictably. The findings were published in a scientific paper in this week’s edition of Nature.
The VIMS instrument, which enables the analysis of a wide range of data including the hydrocarbon composition of the surface of another Saturnian moon, Titan, and the seismological signs of Saturn’s vibrations in its rings, collected more than 200 images of the Enceladus plume from 2005 to 2012.
These data show the plume was dimmest when the moon was at the closest point in its orbit to Saturn. The plume gradually brightened until Enceladus was at the most distant point, where it was three to four times brighter than the dimmest detection. This is comparable to moving from a dim hallway into a brightly lit office.
Adding the brightness data to previous models of how Saturn squeezes Enceladus, the scientists deduced the stronger gravitational squeeze near the planet reduces the opening of the tiger stripes and the amount of material spraying out. They think the relaxing of Saturn’s gravity farther away from planet allows the tiger stripes to be more open and for the spray to escape in larger quantities.
“Cassini’s time at Saturn has shown us how active and kaleidoscopic this planet, its rings and its moons are,” said Linda Spilker, Cassini project scientist at JPL. “We’ve come a long way from the placid-looking Saturn that Galileo first spied through his telescope. We hope to learn more about the forces at work here as a microcosm for how our Solar System formed.”
Enceladus has likely been subject to other gravitational forces over time as well. Previous studies have shown that over hundreds of millions of years, an existing gravitational interaction between Enceladus and another moon, Dione, has caused the orbit of Enceladus to grow increasingly more elongated, or eccentric.
In turn, this produced much more tidal stress in the past and scientists think that contributed to the wide-scale fracturing and friction within Enceladus’ icy crust. The friction leads to melting of internal ice and produces an ocean and eruptions of water and organics on the surface.
This image, the best map ever of the Universe, shows the oldest light in the universe. This glow, left over from the beginning of the cosmos called the cosmic microwave background, shows tiny changes in temperature represented by color. Credit: ESA and the Planck Collaboration.
Earlier this year, a new map of the Cosmic Microwave Background from the Planck spacecraft revealed our Universe was a bit older and is expanding a tad more slowly that previously thought. Additionally, there are certain large scale features that cosmologists cannot readily explain. In fact, because of this finding — possible because of the Planck satellite — we may need to modify, amend or even fundamentally change our description of the Universe’s first moments.
Today, July 31, at 19:00 UTC (12:00 p.m. PDT, 3:00 pm EDT) the Kavli Foundation is hosting a live Google+ Hangout: “A New Baby Picture of the Universe.” You can watch in the player embedded below. You’ll have the chance to ask your questions to Planck scientists by posting on Twitter with the hashtag #KavliAstro, or by email to [email protected]. Questions can be sent prior and during the live webcast. If you miss it live, you can watch the replay here, as well.
You will hear from three leading members of the Planck research team — George Efstathiou and Anthony Lasenby of the Kavli Institute for Cosmology at the University of Cambridge, and Krzysztof Gorski, Senior Research Scientist at the Jet Propulsion Laboratory in Pasadena, CA and faculty member at the Warsaw University Observatory in Poland — and they’ll answer your questions about what was found and what this means to our understanding of the universe.
The surface of Utopia Planitia on Mars. Credit: NASA/JPL/University of Arizona.
The name of this large impact basin on Mars, Utopia Planitia, sounds idyllic. But it also strikes a warm place in the heart of any Trekkie, as in the future (at least in the Star Trek Universe) it will be the location of the facility where the original Starship Enterprise and its many incarnations will be built. While the majority of the Utopia Planitia Shipyards are in geosynchronous orbit of Mars, there are also facilities on the planet as well, according to the Utopia Planitia Yards Starship Guide website. Uptopia Planitia was “found to be the ideal location [for the Shipyard], and a number of planetary sites are developed along with an expansive orbital facility located in geosynchronous orbit directly above,” explains the site.
But back to the present and this beautiful image from the HiRISE camera on board the Mars Reconnaissance Orbiter.
What is striking about the image are the polygon-shaped patterns of troughs and large scallop-shaped depressions. Mike Mellon, writing on the HiRISE website explains that collectively, such landforms are referred to as “thermokarst,” which both point to a slightly warmer and wetter Mars in the past.
Writes Mellon:
Under the proper climate conditions ice may form and seasonally accumulate in a honeycomb network of vertical fractures that appear when ice-rich soil contracts each winter. On Earth this form of subsurface ice is called an “ice wedge.” Special conditions are needed for this ice to accumulate and develop into a large wedge, namely warm temperature and abundant surface water. A thick layer of thawed wet soil forms allowing water to percolate into the open contraction cracks within the permafrost beneath. Later, loss of this wedge ice, by for example sublimation, results in deep depressions marking the honeycomb network.
Likewise, the larger scallop depressions might point to a past climate of frozen ponds or local patches of windblown snow collected in hollows. These surface ice deposits could later be covered by the ever-shifting soils and dust. In either case, the currently bitter cold and dry climate of Mars is not conducive to forming either of these buried-ice forms. Therefore, these landforms point to a warmer, but still cold, climate in the geologic past.
This image just highlights why I’m such a big fan of the HiRISE camera: a gorgeous image of our neighboring planet that was taken just last month from a spaceship orbiting Mars RIGHT NOW that tells us more about the past, while giving hope for our potentially space-faring future.
Members and student involved with the former NASA Lunar Science Institute pose with a sign designating the Institute's new name, the Solar System Exploration and Research Virtual Institute. Credit: SSERVI.
Back in 2008 when NASA was looking to return to the Moon with the Constellation Program, the NASA Lunar Science Institute was established to bridge the science and exploration communities and promote lunar research. Now that NASA is looking at destinations such as asteroids and Mars, as well as the Moon, NLSI will be expanding its reach as well.
It starts with a new name that reflects a broader area of research.
“Our new name is a long one, it’s called the Solar System Exploration Research Virtual Institute, or SSERVI,” said Yvonne Pendleton, the director of NLSI/SSERVI, in a podcast interview with me for the Institute. “It is going to expand beyond our interest of the Moon to include not only the Moon but also near Earth asteroids and the moons of Mars, Phobos and Deimos.”
The new SSERVI logo. Credit: NASA/SSERVI.
Pendelton said the new institute is going to be an expansion upon NLSI, which has been very successful in promoting research and collaboration as well as providing opportunities and support for students.
There were seven different science teams that comprised NSLI, each studying different aspects of the Moon, and for SSERVI there will seven teams as well. Pendleton said they’ve received proposals from many different scientists and “hubs” who are all vying for the seven spots that will make up the new institute. They are currently looking at the proposals and will make a decision and announcement by early October.
“We’re excited about our new teams,” Pendleton said. “There could be some teams from the ‘old’ NLSI, but we’ll definitely have new teams that focus on asteroids and the moons of Mars.”
Pendleton said the change came about because NASA wanted the community to know that “we are now about more than just the Moon. While the Moon is still very important, the name ‘NASA Lunar Science Institute’ sounded so focused on the Moon that people might not realize that our scope has expanded.”
This came from a prompting from John Grunsfeld from NASA’s Science Mission Directorate and Bill Gerstenmaier from the Human Exploration Missions Directorate who decided that a better name was needed. There was an extensive process where they took suggestions for the new name from scientists and the public.
“We hope this is a name that everyone will start to remember — it is a bit of a mouthful to say at first,” Pendleton admitted, “but just think about it as a virtual instate that studies the Solar System, along with the exploration and research that we need to do before we go.”
Pendlton noted that NLSI was also a virtual institute and in many ways pioneered the technology and collaboration tools that will be used for SSERVI.
“NLSI was modeled after the NASA Astrobiology Institute, which the very first virtual instead that NASA had,” Pendleton said. “We are just expanding upon that and using the virtual communications tools as a means to be very inclusive and invite everyone to the table so we can join communities together — in this case exploration and science communities — so that we can ask the right questions and find the best answers before we go to any of these target destinations.”
In fitting with the name “Virtual Institute” this year’s annual Lunar Forum conference was a virtual conference, held completely online with parallel scientific sessions, poster sessions, student lightning round talks and other featured sessions held entirely over the Internet with interactive chat.
A big part of the reason for doing it “virtually” this year was the US budget sequestration and NASA travel restrictions that have been imposed, and while the virtual conference worked well, Pendleton said nothing can replace a conference where scientists have the chance to see each other, collaborate and discuss concepts in person.
It always looked so easy in the Star Trek episodes. “Two to beam up,” Captain James T. Kirk would say from the planet’s surface. A few seconds later, the officers would materialize on the Enterprise — often missing a few red-shirts that went down with them.
A new analysis says the teleportation process wouldn’t take a few seconds. It could, in fact, stretch longer than the history of the universe! “It would probably be quicker to walk,” a press release said laconically.
A spray of dead skin flakes comes off with every sock (screenshot)
The microgravity environment of the ISS poses many challenges to the human body — some more expected than others — but one that many people might not know about is the “molting” of dry skin, notably from the bottom of the feet. And while astronauts living aboard Space Station often spend their days working in socks, when they go to remove them they have to be especially careful to keep floating clouds of flakes at a minimum, lest they incite allergic reactions in their crewmates.
Yeah, you read that right. “Floating clouds of flakes.” Eeeewwwwww.
In the latest episode of ISS Science Garage NASA astronauts Mike Massimino and Don Pettit discuss some of the finer details of podiatric etiquette whilst sojourning aboard the ISS. (Unfortunately saying it fancy-like doesn’t make it any less gross.) All I have to say is, I wouldn’t want to be the one who has to clean out the vent filters.
The solar panels on the MAVEN spacecraft are deployed as part of environmental testing procedures at Lockheed Martin Space Systems in Littleton, Colorado, before shipment to Florida 0on Aug. 2 and blastoff for Mars on Nov. 18, 213. Credit: Lockheed Martin
The solar panels on NASA’s MAVEN Mars orbiter are deployed as part of environmental testing procedures at Lockheed Martin Space Systems in Littleton, Colorado, before shipment to Florida on Aug. 2 and blastoff for Mars on Nov. 18, 2013. Credit: Lockheed Martin Watch cool testing videos below![/caption]
MAVEN is NASA’s next mission to Mars and in less than three days time the spacecraft ships out on a cross country trek for the first step on the long sojourn to the Red Planet.
But before all that, technicians took MAVEN for a final spin test, flexed her solar arrays and bombarded her with sound and a whole lot more.
On Aug. 2, MAVEN (Mars Atmosphere and Volatile EvolutioN Mission) journeys half a continent from its assembly facility at Lockheed Martin in Littleton, Colorado to the Kennedy Space Center and the Florida Space Coast aboard a USAF C-17.
Unlike Curiosity, which is roving across a crater floor on the Red Planet at this very moment, MAVEN is an orbiter with a first of its kind mission.
MAVEN is the first spacecraft from Earth devoted to investigating and understanding the upper atmosphere of Mars.
The goal is determining how and why Mars lost virtually all of its atmosphere billions of years ago, what effect that had on the climate and where did the atmosphere and water go?
To ensure that MAVEN is ready for launch, technicians have been busy this year with final tests of the integrated spacecraft.
Check out this video of MAVEN’s Dry Spin Balance Test
The spin balance test was conducted on the unfueled spacecraft on July 9, 2013 at Lockheed Martin Space Systems in Littleton, Colorado.
NASA says the purpose of the test “is to ensure that the fully integrated spacecraft is correctly balanced and to determine the current center of gravity. It allows the engineering team to fine-tune any necessary weight adjustments to precisely fix the center of gravity where they want it, so that it will perform as expected during the cruise to Mars.”
It was the last test to be completed on the integrated spacecraft before its shipment to Florida later this week.
This next video shows deployment tests of the two “gull-wing” solar panels at Lockheed Martin Space Systems.
Wingtip to wingtip, MAVEN measures 11.43 m (37.5 feet) in length.
In mid May, MAVEN was moved into a Thermal Vacuum Chamber at Lockheed Martin for 19 days of testing.
The TVAC test exposed MAVEN to the utterly harsh temperatures and rigors of space similar to those it will experience during its launch, cruise, and mission at Mars.
MAVEN is slated to blast off atop an Atlas V-401 rocket from Cape Canaveral Air Force Station, Florida on Nov. 18, 2013. The 2000 pound (900 kg) spacecraft will be housed inside a 4 meter payload fairing.
After a 10 month interplanetary voyage it will join NASA’s armada of four robotic spacecraft when it arrives in Mars orbit in September 2014.
Scientists hope that measurements from MAVEN will help answer critical questions like whether, when and how long the Martian atmosphere was once substantial enough to sustain liquid water on its surface and support life.
“What we’re doing is measuring the composition of the atmosphere as a measure of latitude, longitude, time of day and solar activities,” said Paul Mahaffy, of NASA’s Goddard Space Flight Center in Greenbelt, Md, and the principal investigator for MAVEN’s mass spectrometer instrument.
“We’re trying to understand over billions of years how the atmosphere has been lost.”
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Learn more about MAVEN, Cygnus, Antares, LADEE, Mars rovers and more at Ken’s upcoming lecture presentations
Aug 12: “RockSat-X Suborbital Launch, LADEE Lunar & Antares Rocket Launches from Virginia”; Rodeway Inn, Chincoteague, VA, 8 PM
Oct 3: “Curiosity and the Search for Life on Mars – (3-D)”, STAR Astronomy Club, Brookdale Community College & Monmouth Museum, Lincroft, NJ, 8 PM
NASA’s MAVEN orbiter is due to blast off for Mars on Nov. 18, 2013 atop an Atlas V rocket similar to this which launched Curiosity from Cape Canaveral on Nov. 26, 2011. Credit: Ken Kremer/kenkremer.com
