Titan is Saturn’s largest moon and is constantly surprising scientists as the Cassini spacecraft probes under its thick atmosphere. Take its dunes, for example, which are huge and pointed the wrong way.
Why are they pointing opposite to the prevailing east-west winds? It happens during two rare wind reversals during a single Saturn year (30 Earth years), investigators suggest.
Investigators repurposed an old NASA wind tunnel to simulate how Titan is at the surface, watching how the wind affects sand grains. (They aren’t sure what kind of sand is on Titan, so they tried 23 different kinds to best simulate what they think it is, which is small hydrocarbon particles that are about 1/3 the density of what you find on Earth.)
After two years of work with the model — not to mention six years of refurbishing the tunnel — the team determined that the wind must blow 50% faster than believed to get the sand moving.
“It was surprising that Titan had particles the size of grains of sand—we still don’t understand their source—and that it had winds strong enough to move them,” stated Devon Burr, an associate professor at the University of Tennessee Knoxville’s earth and planetary science department, who led the research. “Before seeing the images, we thought that the winds were likely too light to accomplish this movement.”
The winds reverse when the Sun moves over the equator, affecting Titan’s dense atmosphere. And the effects are powerful indeed, creating dunes that are hundreds of yards (or meters) high and stretch across hundreds of miles (or kilometers).
To accomplish this, the winds would need to blow no slower than 3.2 miles per hour (1.4 meters per second), which sounds slow until you consider how dense Titan’s atmosphere is — about 12 times thicker surface pressure than what you would find on Earth. More information on the research is available in the journal Nature.
The Hubble Space Telescope is one of the best observatories humanity has. It’s been operating for nearly 25 years in space, is still highly productive, and is a key element to mission planning for NASA as it sends spacecraft out into the Solar System. When the agency was getting ready to send Dawn to Vesta, for example, it took pictures to help with calibration.
Then Dawn got up close to the dwarf planet in 2011 and found a few surprises — liquid water that possibly flowed temporarily on the surface, for example. And as the spacecraft draws near to Ceres for a close encounter next year, it also will be looking for water — in the form of its atmosphere.
That’s following on from research out of the Herschel Space Telescope published earlier this year, showing that Ceres has a thin water vapor atmosphere surrounding the dwarf planet. It could be producing water similarly to how a comet does, through sublimation, but investigators won’t know much until they get close-up.
“Ceres has some sort of mechanism that’s putting out water vapor and causing a thin, temporary atmosphere,” said Keri Bean, a mission operations engineer at the Jet Propulsion Laboratory who works on Dawn, in a Google+ Hangout yesterday (Dec. 11). “I think that we’re going to try to look into this, and we don’t know what else Ceres will have in store for us.”
Dawn is now so close to Ceres that its pictures will soon exceed the best ones Hubble had to offer. The image above (at right) is modest compared to the space telescope, but in a planned photo session Jan. 26 Dawn will have slightly better pictures than Hubble. By Feb. 4 they will be twice as good in quality and then seven times as good Feb. 20.
The spacecraft’s images not only have science purposes, as they let investigators study the surface, but also serve as optical navigation aids. Ceres is a tiny body and hard to navigate to from far away, so as it gets closer these pictures are crucial for Dawn to figure out where to go next.
Dawn will get its close-up of Ceres in the spring when it arrives at the dwarf planet. To get the latest on the mission, check out the entire Google+ Hangout from yesterday.
NASA’s aging Mars rover is still struggling with Flash memory after several months of controllers trying to work around frequent resets and amnesia events, according to a recent update.
The Opportunity rover is coming up on its 11th anniversary of landing on Mars, and is busy exploring the rim of Endeavour crater, en route to a region that could have clay minerals (showing evidence of water). But the rover has been dogged by frequent memory problems that forced a reformat in September, with only partial success.
While the updates have said the rover is still performing science, NASA says in a Dec. 4 to Dec. 9 update of the mission that the Flash memory was reformatted once again, and that controllers don’t plan to use any of it for the time being. Flash is useful because it retains data even when the rover is turned off. NASA is instead storing “data products” in RAM format.
“Longer term, the project is developing a strategy to mask off the troubled sector of Flash and resume using the remainder of the Flash file system,” NASA stated.
After a brilliant first test flight, and historic Pacific Ocean splashdown and recovery on Dec. 5, 2014, NASA’s Orion spacecraft was brought onshore inside the USS Anchorage to the US Naval Base San Diego and has now been offloaded for the cross country trek back her home base in Florida.
Orion was off-loaded from the well deck of the USS Anchorage Monday night after the amphibious ship docked in San Diego.
NASA officials pronounced the two orbit, 4.5 hour flight maiden test flight of Orion on the Exploration Flight Test-1 (EFT-1) mission to be a complete success.
The EFT-1 spacecraft was recovered at sea, brought to land, and off-loaded by a combined team from NASA, the U.S. Navy, and Orion prime contractor Lockheed Martin.
Years of planning, rehearsals, and hard work on land, in the air, and at sea paid off handsomely for the Orion Recovery Team, led by the Ground Systems Development and Operations Program (GSDO) based at NASA’s Kennedy Space Center in Florida.
“The recovery of Orion was flawless,” said Jeremy Graeber, NASA recovery director. “We wanted to be patient, take our time. We didn’t rush.”
Navy teams in Zodiac boats had attached a collar and winch line to Orion at sea and then safely towed it into the flooded well deck of the USS Anchorage and positioned it over rubber “speed bumps.”
Next they secured Orion inside its recovery cradle and transported it back to US Naval Base San Diego where it was off-loaded from the USS Anchorage.
Orion has now been moved about a mile to the “Mole Pier” where Lockheed Martin has conducted the first test inspection of the crew module and collected test data.
Next, it was placed into the crew module transportation fixture with a rigorous environmental control system and generator to ensure the crew module’s safety during transport.
Orion will be hauled on a flatbed truck across the US for a nearly two-week trip back to Kennedy where it will arrive just in time for the Christmas holidays.
Technicians at KSC will examine every nook and cranny of Orion, and will disassemble it for up close inspection and lessons learned.
Stay tuned here for Ken’s continuing Earth and planetary science and human spaceflight news.
When you’re flying above Earth in a spaceship or space station, taking a clear picture below is more than a point-and-shoot job. As NASA astronaut Don Pettit explains in this video, you need to account for the motion of your little craft to get the best pictures below. And Pettit should know, being a photographer who captured many stunning timelapses in space.
“Apart from everything else an astronaut does on orbit, photography is actually part of our job,” Pettit said in the video. “We take pictures of Earth and the surroundings of Earth, the upper atmosphere. These pictures, in themselves, represent a scientific dataset, recorded now for over 14 years.”
The video is called “From Above” and is a production of SmugMug films, who also did an interview with Pettit. As it turns out, much of the photography taken in space is not of Earth — it’s engineering photography of window smudges or electrical connections to help diagnose problems happening in space.
“These things need to be documented so the images can be downlinked for engineers on the ground to assess what’s happening to the systems on space station,” Pettit said in the interview. “We get training specifically on doing these engineering images, which, for the most part, are not really interesting to the public.”
For a brief period in the 1960s and 1970s, 12 people ventured all the way to the surface of the Moon. The accomplishment at the time was hailed as a political victory over the Soviet Union, but as decades have passed the landings have taken on more symbolic meaning with NASA — a time of optimism, of science and of the American spirit.
The last lunar landing was Apollo 17, which took place on Dec. 11, 1972. Commander Eugene Cernan and lunar module pilot Harrison Schmitt did three moonwalks in the Taurus-Littrow valley, scoping out the highlands to try to get a geologic sense of the area. Among their more memorable findings are orange soil. You can see some pictures from their sojourn below.
Since they were first announced in 2012, NASA has been a major contender in the DARPA Robotics Challenge (DRC). This competition – which involves robots navigating obstacle courses using tools and vehicles – was first conceived by DARPA to see just how capable robots could be at handling disaster response.
The Finals for this challenge will be taking place on June 5th and 6th, 2015, at Fairplex in Pomona, California. And after making it this far with their RoboSimian design, NASA was faced with a difficult question. Should their robotic primate continue to represent them, or should that honor go to their recently unveiled Surrogate robot?
As the saying goes “you dance with the one who brung ya.” In short, NASA has decided to stick with RoboSimian as they advance into the final round of obstacles and tests in their bid to win the DRC and the $2 million prize.
Surrogate’s unveiling took place this past October 24th at NASA’s Jet Propulsion Laboratory in Pasadena, California. The appearance of this robot on stage, to the them song of 2001: A Space Odyssey, was held on the same day that Thomas Rosenbaum was inaugurated as the new president of the California Institute of Technology.
In honor of the occasion, Surrogate (aka “Surge”) strutted its way across the stage to present a digital tablet to Rosenbaum, which he used to push a button that initiated commands for NASA’s Mars rover Curiosity. Despite the festive nature of the occasion, this scene was quite calm compared to what the robot was designed for.
“Surge and its predecessor, RoboSimian, were designed to extend humanity’s reach, going into dangerous places such as a nuclear power plant during a disaster scenario such as we saw at Fukushima. They could take simple actions such as turning valves or flipping switches to stabilize the situation or mitigate further damage,” said Brett Kennedy, principal investigator for the robots at JPL.
RoboSimian was originally created for the DARPA Robotics Challenge, and during the trial round last December, the JPL team’s robot won a spot to compete in the finals, which will be held in Pomona, California, in June 2015.
With the support of the Defense Threat Reduction Agency and the Robotics Collaborative Technology Alliance, the Surrogate robot began construction in 2014. Its designers began by incorporating some of RoboSimian’s extra limbs, and then added a wheeled base, twisty spine, an upper torso, and a head for holding sensors.
Additional components include a the hat-like appendage on top, which is in fact a LiDAR (Light Detection and Ranging) device. This device spins and shoots out laser beams in a 360-degree field to map the surrounding environment in 3-D.
Choosing between them was a tough call, and took the better part of the last six months. On the one hand, Surrogate was designed to be more like a human. It has an upright spine, two arms and a head, standing about 1.4 meters (4.5 feet) tall and weighing about 91 kilograms (200 pounds). Its major strength is in how it handles objects, and its flexible spine allows for extra manipulation capabilities. But the robot moves on tracks, which doesn’t allow it to move over tall objects, such as flights of stairs, ladders, rocks, and rubble.
RoboSimian, by contrast, is more ape-like, moving around on four limbs. It is better suited to travel over complicated terrain and is an adept climber. In addition, Surrogate has only one set of “eyes” – two cameras that allow for stereo vision – mounted to its head, whereas RoboSimian has up to seven sets of eyes mounted all over its body.
The robots also run on almost identical computer code, and the software that plans their motion is very similar. As in a video game, each robot has an “inventory” of objects with which it can interact. Engineers have to program the robots to recognize these objects and perform pre-set actions on them, such as turning a valve or climbing over blocks.
In the end, they came to a decision. RoboSimian will represent the team in Pomona.
“It comes down to the fact that Surrogate is a better manipulation platform and faster on benign surfaces, but RoboSimian is an all-around solution, and we expect that the all-around solution is going to be more competitive in this case,” Kennedy said.
The RoboSimian team at JPL is collaborating with partners at the University of California, Santa Barbara, and Caltech to get the robot to walk more quickly. JPL researchers also plan to put a LiDAR on top of RoboSimian in the future. These efforts seek to improve the robot in the long-run, but are also aimed at getting it ready to face the challenges of the DARPA Robot Challenge Finals.
Specifically, it will be faced with such tasks as driving a vehicle and getting out of it, negotiating debris blocking a doorway, cutting a hole in a wall, opening a valve, and crossing a field with cinderblocks or other debris. There will also be a surprise task.
Although RoboSimian is now the focus of Kennedy’s team, Surrogate won’t be forgotten.
“We’ll continue to use it as an example of how we can take RoboSimian limbs and reconfigure them into other platforms,” Kennedy said.
A United Launch Alliance Altas V 401 rocket like that shown here will launch the next Orbital Sciences Cygnus cargo ship to the space station in place of the Antares rocket. NASA’s Mars-bound MAVEN spacecraft launches atop Atlas V booster at 1:28 p.m. EST from Space Launch Complex 41 at Cape Canaveral Air Force Station on Nov. 18, 2013. Image taken from the roof of the Vehicle Assembly Building (VAB) at NASA’s Kennedy Space Center. Credit: Ken Kremer/kenkremer.com
More photos added[/caption]
Following the catastrophic Oct. 28 failure of an Orbital Sciences Corporation Antares rocket on a critical resupply mission to the space station for NASA, the company is seeking to quickly make up the loss to NASA by announcing the selection of the venerable Atlas V rocket built by United Launch Alliance to launch Orbital’s next Cygnus cargo ship to the orbital science lab.
Orbital and ULA signed a contract to launch at least one, and up to two, Cygnus cargo missions to the International Space Station (ISS) under NASA’s Commercial Resupply Services (CRS) program.
The first Cygnus mission would liftoff sometime late in the fourth quarter of 2015 aboard an Atlas V 401 vehicle from Space Launch Complex 41 (SLC-41) at Cape Canaveral Air Force Station in Florida.
Given that ULA’s full launch manifest was fairly full for the next 18 months, Orbital is fortunate to have arranged one or two available launch slots so quickly in the wake of the Antares launch disaster.
“Orbital is pleased to partner with ULA for these important cargo missions to the International Space Station,” said Frank Culbertson, Orbital executive vice president and general manager of its Advanced Programs Group.
“ULA’s ability to integrate and launch missions on relatively short notice demonstrates ULA’s manifest flexibility and responsiveness to customer launch needs.”
Orbital also stated that there will be “no cost increase to the space agency” by utilizing the Atlas V as an interim launcher.
If necessary, a second Cygnus would be launched by the Atlas V in 2016.
The 401 version of the Atlas uses a 4 meter diameter payload fairing, no solid rocket boosters strapped on to the first stage, and a single-engine Centaur upper stage.
Orbital had been evaluating at least three different potential launch providers.
Observers speculated that in addition to ULA, the other possibilities included a SpaceX Falcon 9 or a rocket from the European Space Agency at the Guiana Space Center.
“We could not be more honored that Orbital selected ULA to launch its Cygnus spacecraft,” said Jim Sponnick, vice president, Atlas and Delta Programs.
“This mission was awarded in a highly competitive environment, and we look forward to continuing ULA’s long history of providing reliable, cost-effective launch services for customers.”
The Orbital-3, or Orb-3, mission that ended in disaster on Oct. 28 was to be the third of eight cargo resupply missions to the ISS through 2016 under the NASA Commercial Resupply Services (CRS) contract award valued at $1.9 Billion.
The highly anticipated launch of the Antares rocket on Oct 28 suddenly went awry when one of the Soviet-era first stage engines unexpectedly exploded and cascaded into a spectacular aerial fireball just above the launch pad at NASA’s Wallops Flight Facility on the Orb-3 mission to the ISS.
Read my earlier eyewitness accounts at Universe Today.
Orbital was awarded a $1.9 Billion contract with NASA under the CRS program to deliver 20,000 kilograms of research experiments, crew provisions, spare parts, and hardware for the eight ISS flights.
In choosing the Atlas V with a greater lift capacity compared to Antares, Orbital will also be able to significantly increase the cargo mass loaded inside the Cygnus by about 35%.
This may allow Orbital to meet its overall space station payload obligation to NASA in 7 total flights vs. the originally planned 8.
The venerable Atlas V rocket is one of the most reliable and well built rockets in the world.
Indeed the Atlas V has been entrusted to launch many high value missions for NASA and the Defense Department – such as MAVEN, Curiosity, JUNO, TDRSS, and the X-37 B.
MAVEN launched on a similar 401 configuration being planned for Cygnus.
The two-stage Atlas rocket is also being man-rated right now to launch humans to low Earth orbit in the near future.
Orbital is still in the process of deciding on a new first stage propulsion system for Antares’ return to flight planned for perhaps sometime in 2016.
Watch here for Ken’s ongoing reporting about Antares and NASA Wallops.
Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.
Here’s the awesome thing about space and social media: in some cases, you can often follow along with a mission almost as soon as the images come to Earth. A group of Canadians is taking that to the next level this month as they take control of the 211th imaging cycle of a powerful camera on the Mars Reconnaissance Orbiter.
While some images need to be kept back for science investigations, the team is sharing several pictures a day on Twitter and on Facebook portraying the views they saw coming back from the High Resolution Imaging Science Experiment (HiRISE) camera. The results are astounding, as you can see in the images below.
“It’s mind-blowing to realize that when the team, myself included, first look at the images, we are likely the first people on Earth to lay eyes upon a portion of the Martian surface that may have not been imaged before at such high resolution,” stated research lead Livio Tornabene, who is part of Western University’s center for planetary science and exploration.
The team will capture up to 150 images between Nov. 30 and Dec. 12, and already have released close to two dozen to the public. Some of the best are below.
.@HiRISE image ESP_039152_1450 Tongue-shaped feature on south mid-latitude crater; Mars sticking its tongue out at us pic.twitter.com/F5LeG5e03m
— Western Mars Imaging (@westernuMars) December 5, 2014
— Western Mars Imaging (@westernuMars) December 5, 2014
Beautiful two-toned ejecta impact crater on Mars! Another lovely image brought to you by @HiRISE#WesternU 🙂 pic.twitter.com/q0FY2r6q8Y — Western Mars Imaging (@westernuMars) December 8, 2014
— Western Mars Imaging (@westernuMars) December 5, 2014
.@HiRISE image ESP_039149_1475 Gully monitoring in crater; looking for various changes over time. #WesternU#LdnOntpic.twitter.com/0DiXo7xrbd — Western Mars Imaging (@westernuMars) December 5, 2014
Can the just-flown Orion spacecraft truly get us to Mars? NASA has been portraying the mission as part of the roadmap to the Red Planet, but there are observers who say a human landing mission is an unrealistic goal given the budget just isn’t there right now in Congress.
That doesn’t stop Boeing from dreaming, though. In this new video, the prime contractor for the future Space Launch System rocket suggests that going to Mars will take six spacecraft elements. Two are in the works right now — Orion and SLS — while a Mars lander and other bits are just ideas right now, but shown in the video.
According to Boeing, the missing elements include a deep-space tug, a habitat, a lander and a rocket designed to get up out of the Mars gravity well. They also suggest it will take several SLS launches to assemble all the pieces to bring humans to the Red Planet.
“I think we’ll be able to colonize Mars someday,” said Mike Raftery, director of Boeing Space Exploration Systems, in the video. “It’ll take time. It may take hundreds of years. But that’s not unusual for humans. It’s really about establishing a human foothold on the planet. It’s a natural evolution of humanity to take this challenge on.”
That said, the video does hold to the old joke that a Mars landing is always 20 years in the future; the opening sequence suggests that the landing would take place in the 2030s and that those first astronauts are between the ages of 10 to 20 right now. What will it take to make the Mars mission possible? Let us know in the comments.
Edit, 3:39 p.m. EST: Thank you to a reader on Twitter, who pointed out this presentation by Boeing that explains the concepts in more detail.