The incredible HiRISE camera on board the Mars Reconnaissance Orbiter turned its eyes away from its usual target – Mars’ surface – and for calibration purposes only, took some amazing images of Earth and our Moon. Combined to create one image, this is a marvelous view of our home from about 127 million miles (205 million kilometers) away.
Alfred McEwen, principal investigator for HiRISE said the image is constructed from the best photo of Earth and the best photo of the Moon from four sets of images. Interestingly, this combined view retains the correct positions and sizes of the two bodies relative to each other. However, Earth and the Moon appear closer than they actually are in this image because the observation was planned for a time at which the Moon was almost directly behind Earth, from Mars’ point of view, to see the Earth-facing side of the Moon.
“Each is separately processed prior to combining (in correct relative positions and sizes), so that the Moon is bright enough to see,” McEwen wrote on the HiRISE website. “The Moon is much darker than Earth and would barely show up at all if shown at the same brightness scale as Earth. Because of this brightness difference, the Earth images are saturated in the best Moon images, and the Moon is very faint in the best (unsaturated) Earth image.”
Earth looks reddish because the HiRISE imaging team used color filters similar to the Landsat images where vegetation appears red.
“The image color bandpasses are infrared, red, and blue-green, displayed as red, green, and blue, respectively,” McEwen explained. “The reddish blob in the middle of the Earth image is Australia, with southeast Asia forming the reddish area (vegetation) near the top; Antarctica is the bright blob at bottom-left. Other bright areas are clouds. We see the western near-side of the Moon.”
HiRISE took these pictures on Nov. 20, 2016, and this is not the first time HiRISE has turned its eyes towards Earth.
Back in 2007, HiRISE took this image, below, from Mars’ orbit when it was just 88 million miles (142 million km) from Earth. This one is more like how future astronauts might see Earth and the Moon through a telescope from Mars’ orbit.
If you look closely, you can make out a few features on our planet. The west coast outline of South America is at lower right on Earth, although the clouds are the dominant features. In fact, the clouds were so bright, compared with the Moon, that they almost completely saturated the filters on the HiRISE camera. The people working on HiRISE say this image required a fair amount of processing to make such a nice-looking picture.
You can see an image from a previous Mars’ orbiter, the Mars Global Surveyor, that took a picture of Earth, the Moon and Jupiter — all in one shot — back in 2003 here.
Following is an excerpt from my new book, “Incredible Stories From Space: A Behind-the-Scenes Look at the Missions Changing Our View of the Cosmos,” which will be released tomorrow, Dec. 20, 2016. The book is an inside look at several current NASA robotic missions, and this excerpt is part 1 of 3 which will be posted here on Universe Today, of Chapter 2, “Roving Mars with Curiosity.” The book is available for order on Amazon and Barnes & Noble.
Seven Minutes of Terror
It takes approximately seven minutes for a moderate-sized spacecraft – such as a rover or a robotic lander — to descend through the atmosphere of Mars and reach the planet’s surface. During those short minutes, the spacecraft has to decelerate from its blazing incoming speed of about 13,000 mph (20,900 kph) to touch down at just 2 mph (3 kph) or less.
This requires a Rube Goldberg-like series of events to take place in perfect sequence, with precise choreography and timing. And it all needs to happen automatically via computer, with no input from anyone on Earth. There is no way to guide the spacecraft remotely from our planet, about 150 million miles (250 million km) away. At that distance, the radio signal delay time from Earth to Mars takes over 13 minutes. Therefore, by the time the seven-minute descent is finished, all those events have happened – or not happened – and no one on Earth knows which. Either your spacecraft sits magnificently on the surface of Mars or lies in a crashed heap.
That’s why scientists and engineers from the missions to Mars call it “Seven Minutes of Terror.”
And with the Mars Science Laboratory (MSL) mission, which launched from Earth in November of 2011, the fear and trepidation about what is officially called the ‘Entry, Descent and Landing’ (EDL) increased exponentially. MSL features a 1-ton (900 kg), 6-wheeled rover named Curiosity, and this rover was going to use a brand new, untried landing system.
To date, all Mars landers and rovers have used — in order — a rocket-guided entry, a heat shield to protect and slow the vehicle, then a parachute, followed by thrusters to slow the vehicle even more. Curiosity would use this sequence as well. However, a final, crucial component encompassed one of the most complex landing devices ever flown.
Dubbed the “Sky Crane,” a hovering rocket stage would lower the rover on 66 ft. (20 meter) cables of Vectran rope like a rappelling mountaineer, with the rover soft-landing directly on its wheels. This all needed to be completed in a matter of seconds, and when the on-board computer sensed touchdown, pyrotechnics would sever the ropes, and the hovering descent stage would zoom away at full throttle to crash-land far from Curiosity.
Complicating matters even further, this rover was going to attempt the most precise off-world landing ever, setting down inside a crater next to a mountain the height of Mount Rainier.
A major part of the uncertainty was that engineers could never test the entire landing system all together, in sequence. And nothing could simulate the brutal atmospheric conditions and lighter gravity present on Mars except being on Mars itself. Since the real landing would be the first time the full-up Sky Crane would be used, there were questions: What if the cables didn’t separate? What if the descent stage kept descending right on top of the rover?
If the Sky Crane didn’t work, it would be game-over for a mission that had already overcome so much: technical problems, delays, cost overruns, and the wrath of critics who said this $2.5 billion Mars rover was bleeding money away from the rest of NASA’s planetary exploration program.
Missions to Mars
With its red glow in the nighttime sky, Mars has beckoned skywatchers for centuries. As the closest planet to Earth that offers any potential for future human missions or colonization, it has been of great interest in the age of space exploration. To date, over 40 robotic missions have been launched to the Red Planet … or more precisely, 40-plus missions have been attempted.
Including all US, European, Soviet/Russian and Japanese efforts, more than half of Mars missions have failed, either because of a launch disaster, a malfunction en route to Mars, a botched attempt to slip into orbit, or a catastrophic landing. While recent missions have had greater success than our first pioneering attempts to explore Mars in situ (on location) space scientists and engineers are only partially kidding when they talk about things like a ‘Great Galactic Ghoul’ or the ‘Mars Curse’ messing up the missions.
But there have been wonderful successes, too. Early missions in the 1960’s and 70’s such as Mariner orbiters and Viking landers showed us a strikingly beautiful, although barren and rocky world, thereby dashing any hopes of ‘little green men’ as our planetary neighbors. But later missions revealed a dichotomy: magnificent desolation combined with tantalizing hints of past — or perhaps even present day – water and global activity.
Today, Mars’ surface is cold and dry, and its whisper-thin atmosphere doesn’t shield the planet from bombardment of radiation from the Sun. But indications are the conditions on Mars weren’t always this way. Visible from orbit are channels and intricate valley systems that appear to have been carved by flowing water.
For decades, planetary scientists have debated whether these features formed during brief, wet periods caused by cataclysmic events such as a massive asteroid strike or sudden climate calamity, or if they formed over millions of years when Mars may have been continuously warm and wet. Much of the evidence so far is ambiguous; these features could have formed either way. But billions of years ago, if there were rivers and oceans, just like on Earth, life might have taken hold.
The Curiosity rover is the fourth mobile spacecraft NASA has sent to Mars’ surface. The first was a 23-pound (10.6 kg) rover named Sojourner that landed on a rock-covered Martian plain on July 4, 1997. About the size of a microwave oven, the 2-foot- (65 cm) long Sojourner never traversed more than 40 feet away from its lander and base station. The rover and lander together constituted the Pathfinder mission, which was expected to last about a week. Instead, it lasted nearly three months and the duo returned 2.6 gigabits of data, snapping more than 16,500 images from the lander and 550 images from the rover, as well as taking chemical measurements of rocks and soil and studying Mars’ atmosphere and weather. It identified traces of a warmer, wetter past for Mars.
The mission took place when the Internet was just gaining popularity, and NASA decided to post pictures from the rover online as soon as they were beamed to Earth. This ended up being one of the biggest events in the young Internet’s history, with NASA’s website (and mirror sites set up for the high demand) receiving over 430 million hits in the first 20 days after landing.
Pathfinder, too, utilized an unusual landing system. Instead of using thrusters to touch down on the surface, engineers concocted a system of giant airbags to surround and protect the spacecraft. After using the conventional system of a rocket-guided entry, heat shield, parachutes and thrusters, the airbags inflated and the cocooned lander was dropped from 100 feet (30 m) above the ground. Bouncing several times across Mars’ surface times like a giant beach ball, Pathfinder eventually came to a stop, the airbags deflated and the lander opened up to allow the rover to emerge.
While that may sound like a crazy landing strategy, it worked so well that NASA decided to use larger versions of the airbags for the next rover mission: two identical rovers named Spirit and Opportunity. The Mars Exploration Rovers (MER) are about the size of a riding lawn mower, at 5.2 feet (1.6 meters) long, weighing about 400 lbs (185 kilograms). Spirit landed successfully near Mars’ equator on January 4, 2004, and three weeks later Opportunity bounced down on the other side of the planet. The goal of MER was to find evidence of past water on Mars, and both rovers hit the jackpot. Among many findings, Opportunity found ancient rock outcrops that were formed in flowing water and Spirit found unusual cauliflower-shaped silica rocks that scientists are still studying, but they may provide clues to potential ancient Martian life.
Incredibly, at this writing (2016) the Opportunity rover is still operating, driving more than a marathon (26 miles/42 km) and it continues to explore Mars at a large crater named Endeavour. Spirit, however, succumbed to a loss of power during the cold Martian winter in 2010 after getting stuck in a sandtrap. The two rovers far outlived their projected 90-day lifetime.
Somehow, the rovers each developed a distinct ‘personality’ – or, perhaps a better way to phrase it is that people assigned personalities to the robots. Spirit was a problem child and drama queen but had to struggle for every discovery; Opportunity, a privileged younger sister, and star performer, as new findings seemed to come easy for her. Spirit and Opportunity weren’t designed to be adorable, but the charming rovers captured the imaginations of children and seasoned space veterans alike. MER project manager John Callas once called the twin rovers “the cutest darn things out in the Solar System.” As the long-lived, plucky rovers overcame hazards and perils, they sent postcards from Mars every day. And Earthlings loved them for it.
While it’s long been on our space to-do list, we haven’t quite yet figured out how to send humans to Mars. We need bigger and more advanced rockets and spacecraft, better technology for things like life support and growing our own food, and we really don’t have the ability to land the very large payloads needed to create a human settlement on Mars.
But in the meantime – while we try to figure all that out — we have sent the robotic equivalent of a human geologist to the Red Planet. The car-sized Curiosity rover is armed with an array of seventeen cameras, a drill, a scoop, a hand lens, and even a laser. These tools resemble equipment geologists use to study rocks and minerals on Earth. Additionally, this rover mimics human activity by mountain climbing, eating (figuratively speaking), flexing its (robotic) arm, and taking selfies.
This roving robotic geologist is also a mobile chemistry lab. A total of ten instruments on the rover help search for organic carbon that might indicate the raw material required by life, and “sniff” the Martian air, trying to smell if gasses like methane — which could be a sign of life — are present. Curiosity’s robotic arm carries a Swiss Army knife of gadgets: a magnifying lens-like camera, a spectrometer to measure chemical elements, and a drill to bore inside rocks and feed samples to the laboratories named SAM (Sample Analysis at Mars) and) and CheMin (Chemistry and Mineralogy). The ChemCam laser can vaporize rock from up to 23 feet (7 meters) away, and identify the minerals from the spectrum of light emitted from the blasted rock. A weather station and radiation monitor round out the devices on board.
With these cameras and instruments, the rover becomes the eyes and hands for an international team of about 500 earthbound scientists.
While the previous Mars rovers used solar arrays to gather sunlight for power, Curiosity uses an RTG like New Horizons. The electricity generated from the RTG repeatedly powers rechargeable lithium-ion batteries, and the RTG’s heat is also piped into the rover chassis to keep the interior electronics warm.
With Curiosity’s size and weight, the airbag landing system used by the previous rovers was out of the question. As NASA engineer Rob Manning explained, “You can’t bounce something that big.” The Sky Crane is an audacious solution.
Curiosity’s mission: figure out how Mars evolved over billions of years and determine if it once was — or even now is — capable of supporting microbial life.
Curiosity’s target for exploration: a 3.4 mile (5.5 km) -high Mars mountain scientists call Mt. Sharp (formally known as Aeolis Mons) that sits in the middle of Gale Crater, a 96-mile (155-km) diameter impact basin.
Gale was chosen from 60 candidate sites. Data from orbiting spacecraft determined the mountain has dozens of layers of sedimentary rock, perhaps built over millions of years. These layers could tell the story of Mars’ geologic and climate history. Additionally, both the mountain and the crater appear to have channels and other features that look like they were carved by flowing water.
The plan: MSL would land in a lower, flatter part of the crater and carefully work its way upward towards the mountain, studying each layer, essentially taking a tour of the epochs of Mars’ geologic history.
The hardest part would be getting there. And the MSL team only had one chance to get it right.
Curiosity’s landing on August 5, 2012 was one of the most anticipated space exploration events in recent history. Millions of people watched events unfold online and on TV, with social media feeds buzzing with updates. NASA TV’s feed from JPL’s mission control was broadcast live on the screens in New York’s Time Square and at venues around the world hosting ‘landing parties.’
But the epicenter of action was at JPL, where hundreds of engineers, scientists and NASA officials gathered at JPL’s Space Flight Operations Facility. The EDL team – all wearing matching light blue polo shirts — monitored computer consoles at mission control.
Two members of the team stood out: EDL team lead Adam Steltzner — who wears his hair in an Elvis-like pompadour — paced back and forth between the rows of consoles. Flight Director Bobak Ferdowski sported and an elaborate stars and stripes Mohawk. Obviously, in the twenty-first century, exotic hairdos have replaced the 1960’s black glasses and pocket protectors for NASA engineers.
At the time of the landing, Ashwin Vasavada was one of the longest serving scientists on the mission team, having joined MSL as the Deputy Project Scientist in 2004 when the rover was under construction. Back then, a big part of Vasavada’s job was working with the instrument teams to finalize the objectives of their instruments, and supervise technical teams to help develop the instruments and integrate them with the rover.
Each of the ten selected instruments brought a team of scientists, so with engineers, additional staff and students, there were hundreds of people getting the rover ready for launch. Vasavada helped coordinate every decision and modification that might affect the eventual science done on Mars. During the landing, however, all he could do was watch.
“I was in the room next door to the control room that was being shown on TV,” Vasavada said. “For the landing there was nothing I could do except realize the past eight years of my life and my entire future was all riding on that seven minutes of EDL.”
Plus, the fact that no would know the real fate of the rover until 13 minutes after the fact due to the radio delay time led to a feeling of helplessness for everyone at JPL.
“Although I was sitting in a chair,” Vasavada added, “I think I was mentally curled up in the fetal position.”
As Curiosity sped closer to Mars, three other veteran spacecraft already orbiting the planet moved into position to be able to keep an eye on the newcomer MSL as it transmitted information on its status. At first, MSL communicated directly to the Deep Space Network (DSN) antennas on Earth.
To make telemetry from the spacecraft as streamlined as possible during EDL, Curiosity sent out 128 simple but distinct tones indicating when steps in the landing process were activated. Allen Chen, an engineer in the control room announced each as they came: one sound indicated the spacecraft entered Mars’ atmosphere; another signaled the thrusters fired, guiding the spacecraft towards Gale Crater. Tentative clapping and smiles came from the team at Mission Control at the early tones, with emotions increasing as the spacecraft moved closer and closer to the surface.
Partway through the descent, MSL went below the Martian horizon, putting it out of communication with Earth. But the three orbiters — Mars Odyssey, Mars Reconnaissance Orbiter and Mars Express — were ready to capture, record and relay data to the DSN.
Seamlessly, the tones kept coming to Earth as each step of the landing continued flawlessly. The parachute deployed. The heat shield dropped away. A tone signaled the descent stage carrying the rover let go of the parachute, another indicated powered flight and descent toward the surface. Another tone meant the Sky Crane began lowering the rover to the surface.
A tone arrived, indicating Curiosity’s wheels touched the surface, but even that didn’t mean success. The team had to make sure the Sky Crane flyaway maneuver worked.
Then, came the tone they were waiting for: “Touchdown confirmed,” cheered Chen. “We’re safe on Mars!”
Pandemonium and joy erupted in JPL’s mission control, at the landing party sites, and on social media. It seemed the world celebrated together at that moment. Cost overruns, delays, all the negative things ever said about the MSL mission seemed to vanish with the triumph of landing.
“Welcome to Mars!” the Director of the Jet Propulsion Laboratory, Charles Elachi said at a press conference following the dramatic touchdown, “Tonight we landed, tomorrow we start exploring Mars. Our Curiosity has no limits.”
“The seven minutes actually went really fast,” said Vasavada. “It was over before we knew it. Then everybody was jumping up and down, even though most of us were still processing that it went so successfully.”
That the landing went so well — indeed perfectly — may have actually shocked some of the team at JPL. While they had rehearsed Curiosity’s landing several times, remarkably, they were never able to land the vehicle in their simulations.
“We tried to rehearse it very accurately,” Vasavada said, “so that everything was in synch — both the telemetry that we had simulated that would be coming from the spacecraft, along with real-time animations that had been created. It was a pretty complex thing, but it never actually worked. So the real, actual landing was the first time everything worked right.”
Curiosity was programmed to immediately take pictures of its surroundings. Within two minutes of the landing, the first images were beamed to Earth and popped up on the viewing screens at JPL.
“We had timed the orbiters to fly over during the landing, but didn’t know for sure if their relay link would last long enough to get the initial pictures down,” Vasavada said. “Those first pictures were fairly ratty because the protective covers were still on the cameras and the thrusters had kicked up a lot of dust on the covers. We couldn’t really see it very well but we still jumped up and down nevertheless because these were pictures from Mars.”
Amazingly, one of the first pictures showed exactly what the rover had been sent to study.
“We had landed with the cameras basically facing directly at Mt. Sharp,” Vasavada said, shaking his head. “In the HazCam (hazard camera) image, right between the wheels, we had this gorgeous shot. There was the mountain. It was like a preview of the whole mission, right in front of us.”
Tomorrow: Part 2 of “Roving Mars With Curiosity,” with ‘Living on Mars Time’ and ‘Discoveries’
“Incredible Stories From Space: A Behind-the-Scenes Look at the Missions Changing Our View of the Cosmos” is published by Page Street Publishing, a subsidiary of Macmillan.
The current divisiveness that seems to be permeating our culture has many wondering if we can ever overcome the divisions to find our common humanity, and be able to work together to solve our problems. I’ve said – only somewhat jokingly — that if there are any alien species out there, waiting to make first contact with the people of Earth in order to unify our planet, now would be a good time.
I saw a quote last week, where in remembering astronaut John Glenn, Bill Nye said “Space exploration brings out our best.”
I really believe that. Space exploration challenges us to not only to be and do our best, but reach beyond the ordinary, push the boundaries of our scientific and technical limits, and then to push even further. That “intangible desire to explore and challenge the boundaries of what we know and where we have been,” as NASA has phrased it, has provided benefits to our society for centuries. With space exploration, our desire to answer fundamental questions about our place in the Universe can not only help to expand technology, but it helps us look at things in new ways and it seems to help foster a sense of cooperation, and – if I may – peaceful and enduring connections with our fellow humans.
If we could only look for and encourage the best in each other, and simply spend time cooperating and working together, I think we’d be amazed at what we could accomplish.
The people involved in space exploration already do that.
Space exploration offers an incredible example of cooperation. Getting a mission off the ground and keeping it operational for as long as possible takes an amazing amount of cooperation. A delightful children’s book titled “Team Moon: How 400,000 People Landed Apollo 11 on the Moon” by Catherine Thimmesh shows how it took hundreds of thousands of people from not just the United States, but also from around the world to send the astronauts to the Moon. From rocket scientists to the seamstresses that sewed the spacesuits together, to the radio operators around the globe that monitored communications, each person, each step was an important link in the chain of what it took to make the Apollo 11 mission possible.
And while my book focuses on NASA missions (I really wish traveling abroad to include missions from other space agencies would have been in my budget!) almost all robotic missions these days are international ventures.
Helmut Jenkner, who is currently the Interim Head of the Hubble Space Telescope Mission, told me that the international nature of the Hubble mission has brought an inherent diversity to the project. The diverse approach to solving problems has helped Hubble be such a successful mission, and with Hubble in space for nearly 27 years, Jenkner said that diverse approach has helped the Hubble mission to endure.
In virtually all robotic missions, scientists from around the world work together and provide their expertise from building instruments to analyzing the data. Working across borders and languages can be difficult, but for the mission to succeed, cooperation is essential. Because of the common goal of mission success, differences from major to petty can be put aside.
On a robotic spacecraft, the many different components and instruments on board are built by different companies, sometimes in several different countries, but yet all the pieces have to fit together perfectly in order for a mission to succeed. Just putting together a mission concept takes an incredible amount of cooperation from both scientists and engineers, as they need to figure out the great compromise of what is possible versus what would be ideal.
I don’t mean to be completely Pollyanna here, as certainly, there are personality conflicts, and I know there are people involved in space missions who have to work side-by-side with someone they don’t really like or don’t agree with. There is also intense competition: the competition for missions to be chosen to get sent to space, the rivalry for who gets to lead and make important decisions, and disagreements on the best way to proceed in times of difficulty. But yet, these people work it out, doing what is necessary in order for the mission to succeed.
Space exploration brings out a sense of inclusiveness. Many of the Apollo astronauts have said that when they traveled to other countries following the missions, people around the world would say how proud they were that “we went to the Moon.” It wasn’t just the US, but “we humans” did it.
When the Curiosity rover landed, when Juno went into orbit around Jupiter, when the Rosetta mission successfully went into orbit around a comet (and then when the mission ended), when New Horizons successfully flew by Pluto, my social media feeds were filled with people around the world rejoicing together.
Being inclusive and encouraging diversity are “mission critical” for going to space, said astrophysicist Jedidah Isler at the recent White House Frontiers Conference. “We have both the opportunity and the obligation to engage our entire population in this epic journey [into space],” she said.
Also at White House Frontiers, President Obama said that “Problem solving through science, together we can tackle some of the biggest challenges we face.”
Dedication and Commitment
Another human aspect that stood out during my interviews is the dedication and commitment of the people who work on these missions to explore the cosmos. Interview after interview, I was amazed by the enthusiasm and excitement embodied by these scientists and engineers, their passion for what they do. I truly hope that in the book, I was able to capture and convey their incredible spirit of exploration and discovery.
Space exploration takes people working long hours, figuring out how to do things that have never been done before, and never giving up to succeed. Alan Stern, Principal investigator for the New Horizons mission to Pluto explained how it took “dedication from 2,500 people around the country who worked all day plus nights and weekends for over 15 years” for the mission to makes its successful flyby of Pluto in July 2015. The dedication continues as the New Horizons team has their sights on another ancient body in the Kuiper Belt that the spacecraft will explore in January 2019.
Taking the larger view.
Space exploration helps us look beyond ourselves.
“A lot of space exploration is taking you out of the trees so you get a glimpse of the forest,” Rich Zurek told me when I visited him at JPL this year. Zurek is the head of NASA’s Mars exploration program, as well as the Project Scientist for the Mars Reconnaissance Orbiter. “A classic example is the Apollo 8 view of the Earth over the Moon’s horizon. You can imagine what the planet looks like but when you actually see it, it is very different and can evoke many different things.”
The first views of Earth from space and seeing the fragileness of our planet from a distance help launch the environmental movement in the 1970’s, which continues today. That planetary perspective is crucial to the future of humanity and our ability solve world-wide problems.
“Working on a project like this gives meaning in general because you are doing something that is outside of yourself, outside of our personal problems and struggles, and you really think about the human condition,” said Natalie Batalha, who is the mission scientist for the Kepler missions’ hunt for planets around distant stars. “Kepler really makes us think about the bigger picture of why we’re here and what we’re evolving towards and what else might be out there.”
Space explorations expands our horizons, feeds our curiosity, and helps us finding all sorts of unexpected things while helping to answer profound questions like how did the Universe begin? How did life begin? Are we alone?
Does that sound too utopian? Like in Star Trek, space exploration offers an optimistic view of the future, and humanity. Star Trek’s “Infinite Diversity from Infinite Combinations” says the only way we grow is through new ideas and experiences, and as soon as we stop exploring, we stop growing.
“We are all confined to Earth but yet we reach out and undertake these grand adventures to space,” said Marc Rayman, who is the director and chief engineer for the Dawn mission to the asteroid belt. He is one of the most passionate people – passionate about space exploration and life itself — I’ve ever talked to. “We do this in order to comprehend the majesty of the cosmos and to express and act upon this passion we feel for exploration. Who hasn’t looked at the night sky in wonder? Who hasn’t wanted to go over the next horizon and see what is beyond? Who doesn’t long to know the universe?”
“Anyone who has ever felt any of those feelings is a part of our mission,” Rayman continued. “We are doing this together. And that’s what I think is the most exciting, gratifying, rewarding and profound aspect of exploring the cosmos.”
“Incredible Stories From Space: A Behind-the-Scenes Look at the Missions Changing Our View of the Cosmos”is available for pre-order on Amazon and Barnes & Noble, with delivery by Dec. 20.
Water has been showing up in all sorts of unexpected places in our Solar System, such as the Moon, Mercury and Jupiter’s moon Ganymede. Add one more place to the list: Asteroid 16 Psyche. This metal-rich asteroid may have traces of water molecules on its surface that shouldn’t be there, researchers say.
Psyche is thought to be the largest metallic asteroid in the Solar System, at 300 km (186 miles) across and likely consists of almost pure nickel-iron metal. Scientists had thought Psyche was made up of the leftover core of a protoplanet that was mostly destroyed by impacts billions of years ago, but they may now be rethinking that.
“The detection of a 3 micron hydration absorption band on Psyche suggests that this asteroid may not be metallic core, or it could be a metallic core that has been impacted by carbonaceous material over the past 4.5 Gyr,” the team said in their paper.
While previous observations of Psyche had shown no evidence for water on its surface, new observations with the NASA Infrared Telescope Facility found evidence for volatiles such as water or hydroxyl on the asteroid’s surface. Hydroxyl is a free radical consisting of one hydrogen atom bound to one oxygen atom.
“We did not expect a metallic asteroid like Psyche to be covered by water and/or hydroxyl,” said Vishnu Reddy, from the University of Arizona’s Lunar and Planetary Laboratory, a co-author of the new paper about Psyche. “Metal-rich asteroids like Psyche are thought to have formed under dry conditions without the presence of water or hydroxyl, so we were puzzled by our observations at first.”
Asteroids usually fall into two categories: those rich in silicates, and those rich in carbon and volatiles. Metallic asteroids like Psyche are extremely rare, making it a laboratory to study how planets formed.
For now, the source of the water on Psyche remains a mystery. But Redddy and his colleagues propose a few different explanations. One is, again, Psyche may not be as metallic as previously thought. Another option is that the water or hydroxyl could be the product of solar wind interacting with silicate minerals on Psyche’s surface, such as what is occurring on the Moon.
The most likely explanation, however is that the water seen on Psyche might have been delivered by carbonaceous asteroids that impacted Psyche in the distant past, as is thought to have occurred on early Earth.
“Our discovery of carbon and water on an asteroid that isn’t supposed to have those compounds supports the notion that these building blocks of life could have been delivered to our Earth early in the history of our solar system,” said Reddy.
If we’re lucky, we won’t have to wait too long to find out more about Psyche. A mission to Psyche is on the short list of mission proposals being considered by NASA, with a potential launch as early as 2020. Reddy and team said an orbiting spacecraft could explore this unique asteroid and determine if whether there is water or hydroxyl on the surface.
Mars’ atmosphere is about 100 times thinner than Earth’s, but there’s still a lot going on in that wispy, carbon dioxide Martian air. The MAVEN spacecraft recently took some exceptional images of Mars using its Imaging UltraViolet Spectrograph (IUVS), revealing dynamic and previously invisible subtleties.
MAVEN took the first-ever images of nightglow on Mars. You may have seen nightglow in images of Earth taken by astronauts on the International Space Station as a dim greenish light surrounding the planet. Nightglow is produced when oxygen and nitrogen atoms collide to form nitric oxide. This is ionized by ultraviolet light from the Sun during the day, and as it travels around to the nightside of the planet, it will glow in ultraviolet.
“The planet will glow as a result of this chemical reaction,” said Nick Schneider, from the Laboratory for Atmospheric and Space Physics at the University of Colorado, Boulder, speaking today at the American Astronomical Society Division for Planetary Sciences meeting. “This is a common planetary reaction that tells us about the transport of these ingredients and around the planet and show how winds circulate at high altitudes.”
MAVEN’s images show evidence of strong irregularities in Mars’ high altitude winds and circulation patterns and Schneider said these first images will lead to an improved understanding of the circulation patterns that control the behavior of the atmosphere from approximately 37 to 62 miles (about 60 to 100 kilometers) high.
MAVEN’s ultraviolet images also provide insight into cloud formation and ozone in Mars atmosphere.
The images show how water ice clouds form, especially in the afternoon, over the four giant volcanoes on Mars in the Tharsis region. Cloud formation in the afternoon is a common occurrence on Earth, as convection causes water vapor to rise.
“Water ice clouds are very common on Mars and they can tell us about water inventory on the planet,” Schneider said. “In these images you can see an incredible expansion of the clouds over the course of seven hours, forming a cloud bank that must be a thousand miles across.”
He added that this is just the kind of info scientists want to be plugging in to their circulation models to study circulation and the chemistry of Mars’ atmosphere. “This is helping us advance our understanding in these areas, and we’ll be able to study it with MAVEN through full range of Mars’ seasons.”
Schneider explained that MAVEN’s unique orbit allows it to get views of the planet that other orbiters don’t have. One part of its elliptical orbit takes it high above the planet that allows for global views, but it still orbits fast enough to get multiple views as Mars rotates over the course of a day.
“We get to see daily events evolve over time because we return to that orbit every few hours,” he said.
In addition, dayside ultraviolet imagery from the spacecraft shows how ozone amounts change over the seasons. Ozone is destroyed when water vapor is present, so ozone accumulates in the winter polar region where the water vapor has frozen out of the atmosphere. The images show ozone lasting into spring, indicating that global winds are constraining the spread of water vapor from the rest of the planet into winter polar regions.
Wave patterns in the ozone images show wind pattern, as well, helping scientists to study the chemistry and global circulation of Mars’ atmosphere.
In the waning days of his presidency, Barack Obama has made a bold statement in favor of the US getting to Mars. Obama didn’t mince any words in his opinion piece written for CNN. He said that America’s next goal in space is “…sending humans to Mars by the 2030s and returning them safely to Earth, with the ultimate ambition to one day remain there for an extended time.”
President Obama has long been a proponent of a strong presence in space for the US, and of the science and technology that supports those efforts. He has argued for healthy NASA budgets in his time, and under his administration, NASA has reached some major milestones.
“Last year alone, NASA discovered flowing water on Mars and evidence of ice on one of Jupiter’s moons, and we mapped Pluto — more than 3 billion miles away — in high-resolution,” Obama said. He also mentioned the ongoing successful hunt for exoplanets, and the efforts to understand asteroids.
Some of his work in support of space and science in general has been more symbolic. His annual White House Science Fairs in particular. He was the first president to hold these fairs, and he hosted 6 of them during his 8 years in office.
Presidents go different directions once they leave office. Some keep a low profile (Bush Jr.), some get targeted for assassination (Bush Sr.), and some become advocates for humanitarian efforts and global peace (Jimmy Carter.) But Obama made it clear that his efforts to promote America’s efforts in space won’t end when his presidency ends. “This week, we’ll convene some of America’s leading scientists, engineers, innovators and students in Pittsburgh to dream up ways to build on our progress and find the next frontiers,” Obama said.
In his piece, Obama gave a laundry list of the USA’s achievements in space. He also pointed out that “Just five years ago, US companies were shut out of the global commercial launch market.” Now they own a third of that market. And, according to Obama, they won’t stop there.
In 2010 he set a goal for American space efforts: to reach Mars by the 2030s. “The next step is to reach beyond the bounds of Earth’s orbit. I’m excited to announce that we are working with our commercial partners to build new habitats that can sustain and transport astronauts on long-duration missions in deep space.” He didn’t elaborate on this in his opinion piece, but it will be interesting to hear more.
Other presidents have come out strongly in favor of efforts in space. The first one was Eisenhower, and Obama mentioned him in his piece. Eisenhower is the one who created NASA in 1958, though it was called NACA (National Advisory Committee for Aeronautics) at the time. This put America’s space efforts in civilian control rather than military.
President Kennedy asked Congress in 1961 to commit to the Apollo program, an effort to get a man on the Moon before the 60s ended. Apollo achieved that, of course, but with only a few months to spare. Kennedy’s successor, President Lyndon Johnson, was a staunch supporter of NASA’s Apollo Program, especially in the wake of disaster.
In 1967 the entire Apollo 1 crew was killed in a fire while testing the craft on its launch pad. The press erupted after that, and Congress began to question the Apollo Program, but Johnson stood firmly in NASA’s corner.
Like some other Presidents before him, Obama has always been a good orator. That was in full view when he ended his piece with these words: “Someday, I hope to hoist my own grandchildren onto my shoulders. We’ll still look to the stars in wonder, as humans have since the beginning of time.”
The focus has really been on Mars lately, and with Obama’s continued support, maybe humans will make it to Mars in the next decade or two. Then, from the surface of that planet, we can do what we’ve always done: continue to look to the stars with a sense of wonder.
With a soft “awwww” from the mission team in the control center in Darmstadt, Germany, the signal from the Rosetta spacecraft faded, indicating the end of its journey. Rosetta made a controlled impact onto Comet 67P/Churyumov–Gerasimenko, sending back incredible close-up images during descent, after two years of investigations at the comet.
“Farewell Rosetta. You have done the job. That was space science at its best,” said Patrick Martin, Rosetta mission manager.
Rosetta’s final resting spot appears to be in a region of active pits in the Ma’at region on the two-lobed, duck-shaped comet.
The information collected during the descent – as well as during the entire mission – will be studied for years. So even though the video below about the mission’s end will likely bring a tear to your eye, rest assured the mission will continue as the science from Rosetta is just getting started.
“Rosetta has entered the history books once again,” says Johann-Dietrich Wörner, ESA’s Director General. “Today we celebrate the success of a game-changing mission, one that has surpassed all our dreams and expectations, and one that continues ESA’s legacy of ‘firsts’ at comets.”
Launched in 2004, Rosetta traveled nearly 8 billion kilometers and its journey included three Earth flybys and one at Mars, and two asteroid encounters. It arrived at the comet in August 2014 after being in hibernation for 31 months.
After becoming the first spacecraft to orbit a comet, it deployed the Philae lander in November 2014. Philae sent back data for a few days before succumbing to a power loss after it unfortunately landed in a crevice and its solar panels couldn’t receive sunlight. But Rosetta continued to monitor the comet’s evolution as it made its closest approach and then moved away from the Sun. However, now Rosetta and the comet are too far away from the Sun for the spacecraft to receive enough power to continue operations.
“We’ve operated in the harsh environment of the comet for 786 days, made a number of dramatic flybys close to its surface, survived several unexpected outbursts from the comet, and recovered from two spacecraft ‘safe modes’,” said operations manager Sylvain Lodiot. “The operations in this final phase have challenged us more than ever before, but it’s a fitting end to Rosetta’s incredible adventure to follow its lander down to the comet.”
Rosetta’s Legacy and Discoveries
Of its many discoveries, Rosetta’s close-up views of the curiously-shaped Comet 67P have already changed some long-held ideas about comets. With the discovery of water with a different ‘flavor’ to that of Earth’s oceans, it appears that Earth impacts of comets like 67P/Churyumov–Gerasimenko may not have delivered as much of Earth’s water as previously thought.
From Philae, it was determined that even though organic molecules exist on the comet, they might not be the kind that can deliver the chemical prerequisites for life. However, a later study revealed that complex organic molecules exist in the dust surrounding the comet, such as the amino acid glycine, which is commonly found in proteins, and phosphorus, a key component of DNA and cell membranes. This reinforces the idea that the basic building blocks may have been delivered to Earth from an early bombardment of comets.
Rosetta’s long-term monitoring has also shown just how important the comet’s shape is in influencing its seasons, in moving dust across its surface, and in explaining the variations measured in the density and composition of the comet’s coma.
And because of Rosetta’s proximity to the comet, we all went along for the ride as the spacecraft captured views of what happens as a comet comes close to the Sun, with ice sublimating and dusty jets exploding from the surface.
Studies of the comet show it formed in a very cold region of the protoplanetary nebula when the Solar System was forming more than 4.5 billion years ago. The comet’s two lobes likely formed independently, but came together later in a low-speed collision.
“Just as the Rosetta Stone after which this mission was named was pivotal in understanding ancient language and history, the vast treasure trove of Rosetta spacecraft data is changing our view on how comets and the Solar System formed,” said project scientist Matt Taylor.
During the final hours of the mission on Friday morning, the instrument teams watched the data stream in and followed the spacecraft as it moved closer to its targeted touchdown location on the “head” of the 4km-wide comet. The pitted region where Rosetta landed appear to be the places where 67P ejects gas and dust into space, and so Rosetta’s swan song will provide more insight into the comet’s icy jets.
“With the decision to take Rosetta down to the comet’s surface, we boosted the scientific return of the mission through this last, once-in-a-lifetime operation,” said Martin. ““It’s a bittersweet ending, but … Rosetta’s destiny was set a long time ago. But its superb achievements will now remain for posterity and be used by the next generation of young scientists and engineers around the world.”
And so, my final day dawns.
Just a few grains are left to drain through
The hourglass of my life.
The Comet is a hole in the sky.
Rolling, turning, a black void churning
Silently beneath me.
Down there, waiting for me, Philae sleeps,
Its bed a cold cave floor,
A quilt of sparkling hoarfrost
Pulled over its head…
I have so little time left;
I sense Death flying behind me,
I feel his breath on my back as I look down
At Ma’at, its pits as black as tar,
A skulls’s empty eye sockets staring back
At me, daring me to leave the safety
Of this dusty sky and fly down to join them,
Never to spread my wings again; never
To soar over The Comet’s tortured pinnacles and peaks,
Or play hide and seek in its jets and plumes…
I don’t want to go.
I don’t want to be buried beneath that filthy snow.
This is wrong! I want to fly on!
There is so much more for me to see,
So much more to do –
But the end is coming soon.
All I ask of you is this: don’t let me crash.
Help me land softly, kissing the ground,
Coming to rest with barely a sound
Like a leaf falling from a tree.
Don’t let me die cartwheeling across the plain,
Wings snapping, cameras shattering,
Pieces of me scattering like shrapnel
Across the ice. Let me end my mayfly life
In peace, whole, not as debris rolling uncontrollably
Into Deir el-Medina…
It’s time to go, I know.
Only hours remain until I join Philae
And my great adventure ends
So I’ll send this and say goodbye.
If I dream, I’ll dream of Earth
Turning beneath me, bathing me in
Fifty shades of blue…
In years to come I hope you’ll think of me
And smile, remembering how, for just a while,
We explored a wonderland of ice and dust
Together, hand in hand.
The search is over, and looking at these images, no wonder it was so hard to find the little Philae lander!
The high-resolution camera on board the Rosetta spacecraft has finally spotted Philae “wedged into a dark crack on Comet 67P/Churyumov-Gerasimenko,” the ESA team said. They also said that now, seeing the lander’s orientation, it’s clear why establishing communications was so difficult following its landing on November 12, 2014.
Rosetta, orbiting the comet and getting ready for its own demise/touchdown on 67P, focused its OSIRIS narrow-angle camera towards a few candidate sites on September 2, 2016 as the orbiter came just 2.7 km of the comet’s surface. Clearly visible in the zoomed in versions are the main body of the lander, along with two of its three legs.
“With only a month left of the Rosetta mission, we are so happy to have finally imaged Philae, and to see it in such amazing detail,” says Cecilia Tubiana of the OSIRIS camera team, the first person to see the images when they were downlinked from Rosetta on September 4.
Tubiana told Universe Today via email that Philae wasn’t too hard to find in the images. “Philae was in hiding in shadow, and as soon as we stretched the brightness to ‘see’ into the shadow, Philae was there!”
She added that nothing else about Philae’s condition has been revealed from the images so far.
The Philae lander was last seen after it first touched down at a region called Agilkia on the odd-shaped, two-lobed comet 67P. During its dramatic touchdown, the lander flew, landed, bounced and then repeated that process for more than two hours across the surface, with three or maybe four touchdowns. The harpoons that were to anchor Philae to the surface failed to fire, and scientists estimated the lander may have bounced as high as 3.2 kilometers (2 miles) before becoming wedged in the shadows of a cliff on the comet. After three days, Philae’s primary battery ran out of power and the lander went into hibernation, only to wake up again and communicate briefly with Rosetta in June and July 2015 as the comet came closer to the Sun and more power was available.
Philae’s final location had been plotted but until yesterday, never actually seen by Rosetta’s cameras. Radio ranging data was used to narrow down the search to an area spanning a few tens of meters, and a number of potential candidate objects were identified in relatively low-resolution images taken from larger distances.
Compare some of the features of the cliff in the image above to this image taken by Philae of its surroundings:
“After months of work, with the focus and the evidence pointing more and more to this lander candidate, I’m very excited and thrilled that we finally have this all-important picture of Philae sitting in Abydos,” said ESA’s Laurence O’Rourke, who has been coordinating the search efforts over the last months at ESA, with the OSIRIS and SONC/CNES teams.
At 2.7 km, the resolution of the OSIRIS narrow-angle camera is about 5 cm/pixel, which is sufficient to reveal features of Philae’s 1 m-sized body and its legs.
“This wonderful news means that we now have the missing ‘ground-truth’ information needed to put Philae’s three days of science into proper context, now that we know where that ground actually is!” says Matt Taylor, ESA’s Rosetta project scientist.
The discovery comes less than a month before Rosetta descends to the comet’s surface. On September 30, the orbiter will be sent on a final one-way mission to investigate the comet from close up, including the open pits in a region called Ma’at, where it is hoped that critical observations will help to reveal secrets of the body’s interior structure.
“Now that the lander search is finished we feel ready for Rosetta’s landing, and look forward to capturing even closer images of Rosetta’s touchdown site,” adds Holger Sierks, principal investigator of the OSIRIS camera.
The Rosetta team said they would be providing more details about the search as well as more images in the near future.
Jupiter’s moon Europa is a juicy target for exploration. Beneath its surface of ice there’s a warm salty, ocean. Or potentially, at least. And if Earth is our guide, wherever you find a warm, salty, ocean, you find life. But finding it requires a dedicated, and unique, mission.
If each of the bodies in our Solar System weren’t so different from each other, we could just have one or two types of missions. Things would be much easier, but also much more boring. But Europa isn’t boring, and it won’t be easy to explore. Exploring it will require a complex, custom mission. That means expensive.
NASA’s proposed mission to Europa is called the Europa Clipper. It’s been in the works for a few years now. But as the mission takes shape, and as the science gets worked out, a parallel process of budget wrangling is also ongoing. And as reported by SpaceNews.com there could be bad news incoming for the first-ever mission to Europa.
At issue is next year’s funding for the Europa Clipper. Officials with NASA’s Outer Planets Assessment Group are looking for ways to economize and cut costs for Fiscal Year (FY) 2017, while still staying on track for a mission launch in 2022.
According to Bob Pappalardo, Europa Clipper’s project scientist at the Jet Propulsion Laboratory, funding will be squeezed in 2017. “There is this squeeze in FY17 that we have,” said Pappalardo. “We’re asking the instrument teams and various other aspects of the project, given that squeeze, what will it take in the out years to maintain that ’22 launch.”
As for the actual dollar amounts, there are different numbers floating around, and they don’t all jive with each other. In 2016, the Europa Mission received $175 million from Congress, but in the administration’s budget proposal for 2017, they only requested $49.6 million.
There’s clearly some uncertainty in these numbers, and that uncertainty is reflected in Congress, too. An FY 2017 House bill earmarks $260 million for the Europa mission. And the Senate has crafted a bill in support of the mission, but doesn’t allocate any funding for it. Neither the Senate nor the Congress has passed their bills.
This is not the first time that a mis-alignment has appeared between NASA and the different levels of government when it comes to funding. It’s pretty common. It’s also pretty common for the higher level of funding to prevail. But it’s odd that NASA’s requested amount is so low. NASA’s own low figure of $49.6 million is fuelling the perception that they themselves are losing interest in the Europa Clipper.
But SpaceNews.com is reporting that that is not the case. According to Curt Niebur, NASA’s program scientist for the Europa mission, “Everyone is aware of how supportive and generous Congress has been of this mission, and I’m happy to say that that support and encouragement is now shared by the administration, and by NASA as well. Everybody is on board the Europa Clipper and getting this mission to the launch pad as soon as our technical challenges and our budget will allow.”
What all this seems to mean is that the initial science and instrumentation for the mission will be maintained, but no additional capacity will be added. NASA is no longer considering things like free-flying probes to measure the plumes of water ice coming off the moon. According to Niebur, “The additional science value provided by these additions was not commensurate with the associated impact to resources, to accommodation, to cost. There just wasn’t enough science there to balance that out.”
The Europa Clipper will be a direct shot to Europa, without any gravity assist on the way. It will likely be powered by the Space Launch System. The main goal of the mission is to learn more about the icy moon’s potential habitability. There are tantalizing clues that it has an ocean about 100 km thick, kept warm by the gravity-tidal interactions with Jupiter, and possibly by radioactive decay in the rocky mantle. There’s also some evidence that the composition of the sub-surface ocean is similar to Earth’s.
Mars is a fascinating target, no doubt about it. But as far as harbouring life, Europa might be a better bet. Europa’s warm, salty ocean versus Mar’s dry, cold surface? A lot of resources have been spent studying Mars, and the Europa mission represents a shift in resources in that regard.
It’s unfortunate that a few tens of million dollars here or there can hamper our search for life beyond Earth. But the USA is a democracy, so that’s the way it is. These discrepancies and possible disputes between NASA and the different levels of government may seem disconcerting, but that’s the way these things get done.
Looking for a way to commemorate the 47th anniversary of the Apollo 11 mission landing on the Moon? Here are a few different ways look back on this historic event and take advantage of advances in technology or new data.
Below is a video that uses data from the Lunar Reconnaissance Orbiter and its amazing suite of cameras, offering a side-by-side view of Apollo 11’s descent, comparing footage originally shot from the Eagle lunar module’s window with views created from reconstructed LRO imagery. This is a fun way to re-live the landing — 1202 alarms and all — while seeing high definition views of the lunar surface.
The National Air and Space Museum in Washington, DC has a special way to mark the Apollo 11 anniversary. They have posted online high-resolution 3-D scans of the command moduleColumbia, the spacecraft that carried astronauts Neil Armstrong, Buzz Aldrin and Michael Collins to the Moon. This very detailed model allows you to explore the entire spacecraft’s interior, which, if you’ve ever visited the Air & Space museum and seen Columbia in person, you probably know is a tremendous ‘upgrade,’ since you can only see a portion of the interior through couple of small hatches and windows. The Smithsonian is also making the data files of the model available for download so it can be 3-D printed or viewed with virtual-reality goggles. Find all the details here.
Here’s a remastered version of the original mission video as aired in July 1969 depicting the Apollo 11 astronauts conducting several tasks during the moonwalk (EVA) operations on the surface of the moon, which lasted approximately 2.5 hours.
If you’re pressed for time, here’s a quick look at the entire Apollo 11 mission, all in just 100 seconds from Spacecraft Films:
Here’s a very cool detailed look at the Apollo 11 launch in ultra-slow motion, with narration: