Space and astronomy news
If someone were to ask you when fear was first discovered, you could tell them August 11, 1877. That’s when, 134 years ago today, Asaph Hall identified Phobos, the larger of Mars’ two moons. But even though it’s named after the Greek god of fear, there’s nothing to be afraid of…
Continue reading “Finding Phobos: Discovery of a Martian Moon”
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CAPE CANAVERAL, Fla. – NASA is experiencing what could be dubbed a “summer of planetary exploration.” With the Juno mission to Jupiter on its way as of Aug. 5, NASA is prepping not one but two more missions – this time to terrestrial bodies – specifically the Moon and Mars.
On Sept. 8 NASA is planning to launch GRAIL (Gravity Recovery And Interior Laboratory). This mirror image spacecraft consists of two elements that will fly in tandem with one another and scan the Moon from its core to its crust. This mission will serve to expand our understanding of the mechanics of how terrestrial bodies are formed. GRAIL will provide the most accurate gravitational map of the Moon to date.
When it comes to upcoming projects that have “celebrity” status – few can compete with the Mars Science Laboratory (MSL) or Curiosity. The six-wheeled rover was part of a media event Friday Aug. 12 that included the “Sky-Crane” jetpack that is hoped will safely deliver the car-sized rover the Martian surface. Also on display was the back half of the rover’s aeroshell which will keep the robot safe as in enters the red planet’s atmosphere.
Numerous engineers were available for interview, one expert on hand to explain the intricacies of how Curiosity works was the Rover Integration Lead on the project, Peter Illsley.
One fascinating aspect of MSL is how the rover will land. As it pops free of the aeroshell, a jet pack will conduct a powered descent to Mars’ surface. From there the rover will be lowered to the ground via wires, making Curiosity look like an alien spider descending from its web. Once the rover makes contact with the ground, the wires will be severed and the “Sky-Crane” will fly off to conduct a controlled crash. Ben Thoma, the mechanical lead on this aspect of the project, described how he felt about what it is like to work on MSL.
MSL is slated to launch this November atop a United Launch Alliance (ULA) Atlas V 541 rocket. If everything goes according to plan the rover will begin exploring Mars’ Gale Crater for a period of approximately two years. In every way Curiosity is an upgraded, super-charged version of the rovers that have preceded her. The Pathfinder rover tested out many of the concepts that led to the Mars Exploration Rovers Spirit and Opportunity and now MSL has incorporated lessons learned to take more robust scientific explorations of the Martian surface.
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The epic multi-year trek of NASA’s Opportunity Mars rover to the gigantic Endeavour crater is nearly complete as the plucky rover blazes to within a football fields distance and first landfall at a spot dubbed “Spirit Point” – named in honor of her long lived twin sister “Spirit”. Endeavour beckons because it may hold clues to a time billions and billions of years ago when Mars was warmer and wetter and harbored an environment that was far more conducive to the formation of life beyond Earth.
Opportunity is racing towards the western foothills of Endeavour’s rim and is at long last transmitting stunningly clear images of portions of the crater ridges, revealing gorgeous vistas and intriguing details up the sloped walls. See our new photo mosaics above and below.
As of today, Aug. 8 on Sol 2680 of the mission, the Martian robot is less than 400 feet (150 m) away from Endeavour’s rim at Spirit Point – which lies at the southern tip of one of the ridges known as “Cape York,” on the western side of Endeavour (see map and photo below). The humongous crater is 14 miles (22 km) in diameter.
“Our primary goal is to get onto the older material at Cape York with the phyllosilicate signatures in CRISM,” said Dr. Matt Golembek in an interview with Universe Today. Golembek is a Senior Research Scientist with the Mars Exploration Program at the Jet Propulsion Laboratory (JPL) in Pasadena, Calif.
The phyllosilicate signatures are based on observations by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) aboard NASA’s Mars Reconnaissance Orbiter (MRO). Phyllosilicates are clay minerals that form in the presence of neutral water and that are more far more hospitable to the possible genesis of life compared to the rocks studied from the more highly acidic aqueous environments examined by the rover thus far.
In mid- 2008, Endeavour crater was chosen as the long term destination for Opportunity by the rover science team because it offers access to older geological deposits than any Opportunity has visited and investigated before. These mineral deposits include phyllosilicates.
Opportunity has been sprinting across the plains of Meridiani since departing her last major science stop at Santa Maria crater in March 2011. See our APOD here.
Opportunity is now heading to a spot called “Odyssey crater” on the way to Spirit Point. See JPL route map below.
“In the end of drive Navcams [navigation camera] from Sols 2678-9, large ejecta blocks on the rim of Odyssey crater are clearly visible and that is our next target to see what those blocks are made of,” Golembek told me.
“After that we will travel north into Cape York to better understand the older rocks in Cape York.”
The rover team is being very careful to not over plan the science activities to far in advance and are keeping their options open.
Eventually, Opportunity will scale the ridge and become the 2nd Martian mountain climber. Spirit was the first Earthly emissary to climb to the summit of a mountain on Mars.
“As we explore we will make more specific plans depending on what we see,” Golembek added.
Measurements from orbiting spacecraft like MRO allowed the science team to target Opportunity more precisely toward those ridges of older exposures of rock outcrops and phyllosilicates observed along Endeavour’s western rim.
Given Opportunity’s rapid progress, it’s now almost certain that she will reach the phyllosiliocates before the Curiosity rover is even launched in Nov. 2011.
Endeavour’s crater rim is discontinuous and divided into a series of segmented mountainous ridges – making it all the more beautiful and a bonanza for science. See the new photo mosaics above and below stitched together by Marco Di Lorenzo and Ken Kremer, illustrating Opportunity’s current vistas.
The Spirit rover succumbed to the bitter Martian arctic-like cold weather during her 4th winter on Mars after roving nearly seven years across Gusev crater. In May 2011, NASA declared Spirit’s mission had concluded after no further communications were received.
Opportunity remains healthy, generates sufficient solar power and has traversed an unbelievable 20.6 miles or 33.2 km since landing on Jan. 24, 2004.
Read my continuing features about Mars starting here
Dramatic New NASA Animation Depicts Next Mars Rover in Action
Opportunity Rover Heads for Spirit Point to Honor Dead Martian Sister; Science Team Tributes
Opportunity Rover Completes Exploration of fascinating Santa Maria Crater
Opportunity Surpasses 30 KM Driving and Snaps Skylab Crater in 3 D
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In a news conference today, NASA announced discoveries that provide additional evidence of seasonal water flows on Mars. Using data collected by the Mars Reconnaissance Orbiter, the MRO team presented images of dark lines that form on slopes during the martian spring/summer and fade in winter.
During the news conference, HIRISE principal investigator Alfred McEwen (University of Arizona), discussed that these “finger-like” features were found in Mars’ mid-southern latitudes. “The best explanation for these observations so far is the flow of briny water,” he said.
McEwen based his explanation on several key facts: First, salt lowers the freezing point of water (“plain” water would simply stay frozen on Mars) Secondly, the temperature on Mars during these flows ranges from -23 to +27 degrees Celsius, which rules out CO2. While there is significant evidence of flowing water, the team did state that there is no direct detection of water since it evaporates quickly on Mars.
Regarding the dark color of the flows, McEwen added, “The flows are not dark because of being wet, they are dark for some other reason.” McEwen also mentioned that researchers will need to re-create Mars-like conditions in the lab to better understand these flows, stating, “It’s a mystery now, but I think it’s a solvable mystery with further observations and laboratory experiments.”
MRO Project Scientist Richard Zurek (JPL) offered his thoughts as well. “These dark lineations are different from other types of features on Martian slopes,” he said, “and repeated observations show they extend ever farther downhill with time during the warm season.”
What also proves intriguing to the team is that while gullies are very abundant on colder slopes that face the poles, the dark flows discussed in today’s news conference are found on warmer slopes which face the equator.
During the conference, Philip Christensen (Arizona State University) presented a map showing concentrations of “salts” in the same locations that the dark, “finger-like” flows were found.
McEwen reiterated during the Q&A session that the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM), hasn’t detected any signs of water and that laboratory simulations will be necessary to gain a better understanding of these features – basically the team is seeing signs of flowing water, but not the water itself.
If you’d like to learn more about the Mars Reconnaissance Orbiter and today’s announcement, you can visit: http://www.nasa.gov/mro
To see more images related to the new findings, see this link from JPL.
Sources: NASA/JPL News Conference, NASA/JPL News
Back in 1979, scientists at Stanford University created a 3-D movie from images sent back by the Viking landers on Mars. It was rather novel in that, while 3-D movies had been around since the 1950’s — mostly for low-budget B movies in theaters — this stereographic film was more scientific in nature, but was created for the public to learn more about the Viking mission and Mars, providing a “you are there” experience. It was created using 16mm film, which degrades over time. Considering the unique historical and scientific value of this film, a group from NASA’s Ames Research Center have constructed a new remastered digital version, made from the original 16mm film footage, sound reels, and related documentation.
Plans are underway to hold screenings of this new version of Mars in 3-D in Digital Cinema 3-D format. But in the meantime you can watch it now online in a digital anaglyph version, best viewed with red-cyan 3-D glasses.
Read more about the remastering process and read original papers from the imaging team from Viking at the Ames History Office website.
Last week scientists, engineers and others who work on the Mars Exploration Rover mission paid tribute to the Spirit rover which explored Mars for six years before succumbing to the harsh Martian winter in 2010. I was away at a conference last week and missed it, but fortunately the event was recorded and you (and I!) can watch it below. Above is a video photo diary of Spirit’s accomplishments on Mars.
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It’s official: the Mars Science Laboratory rover, Curiosity, will be landing Gale Crater on Mars. Scientists announced the final decision at a special event at the Smithsonian’s National Air and Space Museum Friday morning. Comparing the terrain to an enticing bowl of layered Neopolitan ice cream, the science team announced the rover will land at the foot of a layered mountain inside Gale Crater.
“The science at Gale is going to be amazing and it will be a beautiful place to visit,” said Dawn Sumner, a geologist with the MSL team.
MSL is scheduled to launch in November 2011 from NASA’s Kennedy Space Center in Florida and land in August 2012. Curiosity is twice as long and more than five times as heavy as previous the Mars Exploration rovers Spirit and Opportunity. The rover will study whether the landing region at Gale crater had favorable environmental conditions for supporting microbial life and for preserving clues about whether life ever existed.
News had leaked out a few weeks ago that Gale was the favored site, but scientists today explained what made Gale stand out among the four final candidates, which each offered their own delicious “flavor,” making the decision a difficult one.
“When it comes down to four landing sites, it comes down to what feels right,” said John Grotzinger, Mars Science Laboratory project scientist. “We as a science team, as a community, we got together and in the end we picked the one that felt best. Why? Here, we’ve got mountain of rocks, taller than Mount Whitney. It looks like Hawaii; it’s not a tall spire, but a broad mound. So we can actually climb up this mountain with the rover. That alone justifies sending the spacecraft there. It turns out, though, the most attractive science sites are at the base of the mountain. We can address the principle goals of the things the Mars community would like answers to.”
NASA’s strategy for Mars has been to “follow the water,” since we know that wherever there is water on Earth, there is life. Scientists are hedging their bets on Mars that wherever liquid water once flowed would be the best places to look for evidence of past habitability.
Gale has that going for it.
The portion of the crater where Curiosity will land has an alluvial fan likely formed by water-carried sediments. The layers at the base of the mountain contain clays and sulfates, both known to form in water.
“It’s a huge crater sitting in a very low-elevation position on Mars, and we all know that water runs downhill,” Grotzinger said. “In terms of the total vertical profile exposed and the low elevation, Gale offers attractions similar to Mars’ famous Valles Marineris, the largest canyon in the solar system.”
The scientists emphasized that MSL is not a life detection mission, as it can’t look for fossils. But it can detect organic carbon, which can tell the early environmental story of Mars, found in the sediments within rocks.
Gale Crater crater spans 154 kilometers (96 miles) in diameter and is about the combined area of Connecticut and Rhode Island. The mound in the center rises 5 km (3 miles) height and the Layering in the mound suggests it is the surviving remnant of an extensive sequence of deposits.
The crater is named for Australian astronomer Walter F. Gale.
About the size of a Mini-Cooper, Curiosity has 17 cameras and a full color video camera. The mission should offer incredible vistas that will likely wow the public, beginning with the landing, as Curiosity will take a full color, high definition movie as it descends on the “Sky Crane” landing system.
Anyone else ready for this mission to get going?
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A next-generation plasma rocket being developed by former NASA astronaut Franklin Chang Diaz called the Variable Specific Impulse Magnetoplasma Rocket (VASIMR) has been touted as a way to get astronauts to Mars in weeks rather than months, as well as an innovative, cheap way to re-boost the International Space Station. But in a biting commentary posted on Space News and the Mars Society website, “Mars Direct” advocate Robert Zubrin calls VASIMR a “hoax” saying the engine “is neither revolutionary nor particularly promising. Rather, it is just another addition to the family of electric thrusters, which convert electric power to jet thrust, but are markedly inferior to the ones we already have,” adding, “There is thus no basis whatsoever for believing in the feasibility of Chang Diaz’s fantasy power system.”
The VASIMR uses plasma as a propellant. A gas is ionized using radio waves entering into a plasma state. As ions the plasma can be directed and accelerated by a magnetic field to create specific thrust. The purported advantage of the VASIMR lies in its ability to change from high impulse to low impulse thrust as needed, making it an ideal candidate for a mission beyond low Earth orbit.
Chang Diaz’ company, the Ad Astra Rocket Company successfully tested the VASIMR VX-200 plasma engine in 2009. It ran at 201 kilowatts in a vacuum chamber, passing the 200-kilowatt mark for the first time. “It’s the most powerful plasma rocket in the world right now,” said Chang-Diaz at the time. Ad Astra has signed a Space Act agreement with NASA to test a 200-kilowatt VASIMR engine on the International Space Station, reportedly in 2013.
The tests would provide periodic boosts to the space station, which gradually drops in altitude due to atmospheric drag. ISS boosts are currently provided by spacecraft with conventional thrusters, which consume about 7.5 tons of propellant per year. By cutting this amount down to 0.3 tons, Chang-Diaz estimates that VASIMR could save NASA millions of dollars per year.
For the engine to enable trips to Mars in a reported 39 days, a 10- to 20-megawatt VASIMR engine ion engine would need to be coupled with nuclear power to dramatically shorten human transit times between planets.
Zubrin is the president of the Mars Society and author of the book “The Case for Mars: The Plan to Settle the Red Planet and Why We Must.” He has long touted the “Mars Direct” approach of getting humans to Mars to create a sustainable human settlement. The plan includes a series of unmanned and human flights to Mars using existing technology, as well as “living off the land” on Mars by creating rocket fuel to return to Earth, and using underground reservoirs of water on Mars.
In his commentary on VASIMR, Zubrin says, “existing ion thrusters routinely achieve 70 percent efficiency and have operated successfully both on the test stand and in space for thousands of hours. In contrast, after 30 years of research, the VASIMR has only obtained about 50 percent efficiency in test stand burns of a few seconds’ duration.”
On the ‘39 days to Mars’ claim, Zubrin says VASIMR would need to couple with a nuclear reactor system with a power of 200,000 kilowatts and a power-to-mass ratio of 1,000 watts per kilogram, while the largest space nuclear reactor ever built, the Soviet Topaz, had a power of 10 kilowatts and a power-to-mass ratio of 10 watts per kilogram.
Zubrin has invited Chang Diaz to a formal public debate the VASIMR at a Mars Society convention in Dallas next month.
Read Zubrin’s commentary on Space News or the Mars Society website.
More info: Ad Astra Rocket Company
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Although a rumor came out about a week and a half ago that Gale Crater was the scientists’ preferred landing site for the Mars Science Laboratory, officially NASA says the finalists are now down to two: Gale and Eberswalde craters. The final selection will likely be made sometime this month, no earlier than July 11. As of now, MSL, a.k.a Curiosity scheduled to head to Mars during a Nov. 25 to Dec. 18, 2011 launch window.
Gale Crater contains ancient lakebed deposits and sitting in the middle of the crater is an enticing 5-kilometer-tall mound of rock, stacked with layers. This could provide the rover a study a variety of environments that produced clay deposits near the mountain’s base to later environments that produced sulfate deposits partway up the slope.
Eberswalde is the site of what scientists think is a former river delta, where organic materials could be waiting to be analyzed. NASA says that as a clay-bearing site where a river once flowed into a lake, Eberswalde crater offers a chance to use knowledge that oil industry geologists have accumulated about where in a delta to look for any concentrations of carbon chemistry, a crucial ingredient for life.
Officially out of the running are Mawrth Vallis and Holden Crater, the other two finalist sites.
The spacecraft will arrive at Mars in August 2012, and land via its unusual “sky crane” landing system. (See a video of it here.) Researchers will use the rover’s 10 science instruments for at least two years to investigate whether the landing area has ever offered environmental conditions favorable for microbial life.
Source: NASA
Is there — or was there ever — life on Mars? And will we ever definitively find out? After multiple unmanned missions to Mars, we still can’t answer those questions, but the possibility of life on the Red Planet has intrigued us for decades and our interest in Mars still runs high. Here’s a video produced by the PBS affiliate in San Francisco, California, KQED and their science and environment series QUEST. It looks at our past fascination of Mars and how NASA scientists are hoping the Mars Science Lab rover will help them solve the mysteries of Mars.