spacEurope’s most recent resident columnist, Stuart Atkinson, has dressed his intrepid reporter outfit and embarked on a journey that took him towards Mars, its arctic, its secrets and correspondent unravelling, all this by taking advantage of a very special ride.
Let us read the first of Stu’s adventure as spacEurope’s inquirer.
Mars is one day nearer, this blog is one post richer…
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Although several orbiters have been circling the Red Planet for several years now, returning amazingly-detailed images of the planet’s surface, it’s true to say that since 2004 the “plucky little Mars rovers” Spirit and Opportunity have been in the media and public spotlight the most. Their day to day adventures, trekking across Mars like silent R2D2s, taking images of Mars’ craters, rocks, skies and landscape have captured the imaginations and hearts of scientists, space enthusiasts and the general public alike. They’ve survived dust-storms, mechanical and software glitches, even political fights here on Earth to become silicon celebrities.
But in just under two months that spotlight will swing away from the rovers and blaze on another piece of amazing hardware: Phoenix. Unlike the MERs Phoenix will stay exactly where it is once it lands, because it’s just that, a lander. But it’s a lander unlike any other because it will be coming down up near the planet’s north pole and sending us back the first, long-awaited images of an entirely new region of Barsoom.
Oh, and it has a chance of finding life on Mars, too….
Already the Phoenix mission is being supported and publicised superbly on the internet, with many websites devoted to it. One of the most fascinating has to be the “Phoenix Blog”, where many members of the team write about their work, as well as their hopes for the mission. Some of the most enlightening and informative entries have been written by Mark Lemmon, described in that typically cold NASA-speak way as simply “Co-Investigator, SSI Lead, Dust Cycles, Texas A&M University”. Decode that and what you find is that Mark Lemmon will serve as the scientific lead for the Surface Stereo Imager, SSI. (If you don’t know what that is, the Phoenix website explains: SSI will serve as Phoenix's "eyes" for the mission, providing high-resolution, stereo, panoramic images of the martian arctic. Using an advanced optical system, SSI will survey the arctic landing site for geological context, provide range maps in support of digging operations, and make atmospheric dust and cloud measurements.
Basically, he’s an “image guy”.
And so am I! So, with the days to landing ticking away, I thought I’d cheekily email Mark and ask him the questions I hadn’t found answers to anywhere else. As usual when emailing scientists like him, I half-expected a polite “Sorry, I’m too busy… PLANNING A MISSION TO MARS!!!!” email to come back, but, as has always been the case – with NASA scientists, anyway – he generously took the time out of what must be an insanely crazy schedule to answer some questions for me and spacEurope too.
With just a couple of months left to go until Landing Day, what’s the mood like in the Phoenix team? Have the recent successful tests and simulations relaxed everyone, or just made them more nervous as the days tick by?
Although several orbiters have been circling the Red Planet for several years now, returning amazingly-detailed images of the planet’s surface, it’s true to say that since 2004 the “plucky little Mars rovers” Spirit and Opportunity have been in the media and public spotlight the most. Their day to day adventures, trekking across Mars like silent R2D2s, taking images of Mars’ craters, rocks, skies and landscape have captured the imaginations and hearts of scientists, space enthusiasts and the general public alike. They’ve survived dust-storms, mechanical and software glitches, even political fights here on Earth to become silicon celebrities.
But in just under two months that spotlight will swing away from the rovers and blaze on another piece of amazing hardware: Phoenix. Unlike the MERs Phoenix will stay exactly where it is once it lands, because it’s just that, a lander. But it’s a lander unlike any other because it will be coming down up near the planet’s north pole and sending us back the first, long-awaited images of an entirely new region of Barsoom.
Oh, and it has a chance of finding life on Mars, too….
Already the Phoenix mission is being supported and publicised superbly on the internet, with many websites devoted to it. One of the most fascinating has to be the “Phoenix Blog”, where many members of the team write about their work, as well as their hopes for the mission. Some of the most enlightening and informative entries have been written by Mark Lemmon, described in that typically cold NASA-speak way as simply “Co-Investigator, SSI Lead, Dust Cycles, Texas A&M University”. Decode that and what you find is that Mark Lemmon will serve as the scientific lead for the Surface Stereo Imager, SSI. (If you don’t know what that is, the Phoenix website explains: SSI will serve as Phoenix's "eyes" for the mission, providing high-resolution, stereo, panoramic images of the martian arctic. Using an advanced optical system, SSI will survey the arctic landing site for geological context, provide range maps in support of digging operations, and make atmospheric dust and cloud measurements.
Basically, he’s an “image guy”.
And so am I! So, with the days to landing ticking away, I thought I’d cheekily email Mark and ask him the questions I hadn’t found answers to anywhere else. As usual when emailing scientists like him, I half-expected a polite “Sorry, I’m too busy… PLANNING A MISSION TO MARS!!!!” email to come back, but, as has always been the case – with NASA scientists, anyway – he generously took the time out of what must be an insanely crazy schedule to answer some questions for me and spacEurope too.
With just a couple of months left to go until Landing Day, what’s the mood like in the Phoenix team? Have the recent successful tests and simulations relaxed everyone, or just made them more nervous as the days tick by?
Mark Lemmon - Seeing the current sol tick below -100 to a 2-digit number certainly helped raise the anxiety level. There is still much to do, and we are still learning things. However, we have demonstrated the ability to do what we need to, and can now focus more on "do better" and on handling more types of problems. The best news is how well the EDL team has performed in simulations, tests, and reviews. There is good confidence among the whole team that the EDL team is ready.
As a new broadband user (stop laughing!) I’ve been spending waaaay too much time looking at HiRISE images with the wonderful IAS Viewer, and I couldn’t help but notice that all the images of potential Phoenix landing sites looked like they were strewn with chunks of rock, so I had to ask about that…
HiRISE images of the polar terrain in which Phoenix might land show boulders, boulders and more boulders. Is the team confident that they can steer Phoenix to a landing amongst these obstacles? Or are you secretly wondering if all your panoramas will have sloping horizons after Phoenix lands with one leg on a boulder..?
ML - They tell me the leg that lands on a boulder will crush more than the others, leveling out the lander deck. More to the point, the "Green Valley" location is a safer place to land than the Viking 2 site, and Phoenix can handle VL2. There are areas of bad patches, but the 1-sigma landing ellipse is nearly free of large boulders. When the first HiRise images of Box D came down in October 2006, there was a very different feeling--there was no safe ellipse there.In the last 3 tests, we've had the lander near the maximum rated tilt. Things have gone well--and certainly the ability to take good pictures has not been compromised. In one test, a boulder had even broken (pure simulation, of course) a solar array.
Having seen those same HiRISE images, has the team been able to put together a picture of what the “Local scenery” might look like after touchdown? Low hills? Mounds? Cracked ground? Frost patches?
ML - There are places where low hills might be seen, and others where localization from horizon images will be as difficult as for VL2. (Fortunately a couple UHF passes and then a HiRise image will be enough to find the lander quickly.) There's a good chance of seeing the polygonal terrain, but the ground fractures may not be deep and some may be difficult to see from too close. We're hopeful that we'll have a trough in the robotic arm's workspace. Overall, I'd expect some resemblance to the VL2 site, with fewer large rocks, and some resemblance to pictures we've been seeing from patterned ground in the Antarctic Dry Valleys.
Like many spacEurope readers I’ll be following the landing online, watching events unfold over NASA TV, just as I did with the MERs all those years ago. So an obvious question sprang to mind…
Where will you be during the landing? Set the scene for us… will you be watching quietly at a desk, on your own? Watching monitors with other team members? Hiding in a toilet, unable to watch?...
ML - For the first time, I'll be watching with my family. There is no science telemetry to monitor at touchdown, and there is a team member and family party with NASA TV and such near the operations area. Shortly after landing, I'll head down the hall and prepare for the first communications pass after Phoenix settles on Mars. I'm not one of the unlucky few required to be at JPL. Tucson is where the action will be once the footpads are on the ground. Peter Smith, the PI, and other big shots have to be at JPL--Entry, Descent, and Landing is run from there--and are supposed to stay there for a couple days until "the keys" are handed to UA. But the mechanisms for evaluating health and safety and for generating commands are clustered in Tucson (and in Denver for the spacecraft team). The tension builds quickly once the monitors show approach velocity increasing--when Mars' gravity takes over, things are about to start happening fast. It really build up after cruise-stage separation. We temporarily lose sight of what's going on before the orbiters pick up a signal during EDL. Each event brings relief and renewed tension, and no matter how well things are going near touchdown, the seconds or minutes between thrusters-off and positive confirmation there is still a signal will be as tense as it can get. At least we don't have to go through the MER landing ("remember, you have to survive ALL the bounces").
It'll be fun to celebrate with family, briefly. Then the tension comes back for the first communications relay--a lot had to happen between touchdown and the first communications, and we'll be waiting for the proof that we have a lander in a good power situation with healthy systems.
I know that Phoenix will be a “hard science” mission, taking lots of measurements and readings etc, but – with the greatest respect to the scientists involved in those parts of the mission, I’m not that excited by graphs or charts. I want pictures! So of course I had to ask the question that’s occupying my thoughts the most…
An obvious and impatient question, I’m sorry, but one everyone is wanting to ask: how soon after the landing do you think all of us watching online will see the first picture from Phoenix? And what will it be of?
ML - Touchdown is a bit after 4 pm Phoenix (Mars) time--and Phoenix time is reasonably aligned with Tucson (and Pasadena) time on sol 0. About 6 pm, Phoenix sends data to Odyssey, including telemetry showing critical deployments as well as the first images. Not all of the images will come down at this time, some will wait for a 4 am Odyssey relay.
We do not know exactly how many pictures we get. It will depend on the mode of landing and the timing of some deployment events. There is a certain time the spacecraft will shut down to conserve energy--there's an outside chance we land with a bad battery or have a bad solar array deployment, so better safe than sorry. SSI takes as many images as possible before shutdown.
The first image will be of the plus-Y solar array ("SAPY"), across the lander deck from SSI. This is followed by 3 images of the opposite solar array ("SAMY"). We'll see a bit of Mars in the background, but the point is to diagnose any possible problems with power generation. Then we get the Neil Armstrong shot--a stereo pair of the footpad below SSI. Finally, we start a 2-color panorama of the northern landscape. We don't expect Phoenix to get too far into this, but we should get a small panorama.
I would hope this stream out over NASA TV and the web immediately, but I'm sure JPL will kindly volunteer to host a midnight press conference releasing the first set of images.
How soon can we expect to be drooling over the first real colour panorama of the landing site?
ML - Sadly--from my perspective--not very soon. There are many competing needs, including many needs for images. Much more so than for the Rovers' Pancam, SSI has an operations role that competes with its science role.We'll start with a 1-color panorama (at MER Navcam-like resolution), and follow that up with some isolated colour imaging. depending on how things go, we'll start a 360-degree colour panorama by sol 6 or so (earlier only if other things don't go as planned--or things go exceptionally well).
The next question was a biggie. We’ve all got used to – probably spoiled by – being able to see new “raw” images of Mars, and Saturn, every day. This has been a huge and very welcome shift from the way things were done in the past. Would this policy continue with Phoenix…?
After the landing will “raw” images be released swiftly and freely on a Phoenix website as happens with Cassini and the MERs, or will there be a gradual release of images, as the MESSENGER team are doing now? And will you be encouraging members of the public to comment on the images in any way?
ML - The Phoenix project is committed to the quick release of images, and this is strongly supported by the PI and by the imaging leads. In the proposal, we made 48-hour release a "level-1" requirement, and signed up JPL to do the release in a MER-like way (planning to beat the 48-hour timeline, of course).I know there are several outreach programs. I certainly think any encouragement we can give is good. I would hope that at some point we will be able to feature some especially good outside contributions (mosaics, true, false, or simulated color images, etc.) alongside our own--but I can make no promises (i.e., my opinions are my own ...).
Enough science… for now… Time to get a little more personal…
What are your own personal hopes – and fears – for the mission? The “plucky little Mars rovers” Spirit and Opportunity have – rightly – enjoyed incredible media coverage, and have really been taken to many people’s hearts. Do you think Phoenix will enjoy less media attention because it is a static lander? How will the Phoenix team be seeking to maximise media and public interest in the mission?
ML - I think much as the rovers make it back into the news when new discoveries are announced or major goals are reached, Phoenix will be in and out of the news. Certainly there will be a lot of coverage at first, and it will never reach those levels again--the same as for any landed mission--short of a major discovery. However, Phoenix has great potential for major discoveries. There will be day to day drama of the digging. In principle, that could exceed, for instance, driving around a photogenic crater rim. In practice, we'll have many things to slow progress--sols devoted to chemical analyses are critical, but not visually stimulating. And then, as we find ice, sample ice, and are able to talk meaningfully about habitability on Mars, I think Phoenix can regain some of the public attention.
The MER teams are still working with their rovers several years after they were supposed to have “died”. That isn’t a possibility for the Phoenix team, as you know in advance that the lander will perish several months after landing as the conditions at its landing site deteriorate. How does that knowledge affect the team? Does it make you frustrated that you’ll be “against the clock” from the second you land? Or does it help you focus, and be determined to be as productive and efficient as possible?
ML - The clock will be ticking fast. Phoenix could last maybe 150 sols--but daily digging operations cannot last that long. We have to complete our major mission requirements in around the 90 sol time frame. The facts that we have to learn to live with are that it takes time to complete an investigation, yet we need to save time so we can dig and get in all the investigations we want. To use TEGA and all of MECA on a single layer could easily use more than a week. However, on that front I expect we'll have more energy available per sol in the real mission than we have practiced using--thus I hope we can do more in a sol.I think this brings the good kind of tension, a creative tension. There will be smart people with good arguments on both sides--more detailed work now, versus saving more time for the next digging and sampling cycles. Having that pressure will, I think, lead to a more efficient mission.
Realising how precious Mark’s time is, I’d promised I’d only ask ten questions, which meant one left. There were lots of questions I could have asked, but there was only one more thing I really wanted to know… And finally, the question that is on many people’s minds, throughout the professional Mars exploration community and space “enthusiast” community, right through kids at school and the general public: with all its instruments and detectors, if it’s there to be found, is it possible that Phoenix might actually find life on Mars? Is that a genuine, scientific possibility? Do YOU think it might?
ML - There are those that think finding life is possible with Phoenix, within the project and outside. I don't, short of off the charts serendipity. So, I wouldn't want to stake the mission's perceived success on having a bug crawl around in microscope images. I do expect that Phoenix will find a very interesting environment in the ice layer, and the Phoenix results (whatever they are) will greatly increase the excitement for the prospects of finding life.
I’d like to thank Mark for taking the time to answer these questions for spacEurope so fully, enthusiastically and personally, too.
Stuart Atkinson
Editor's note: Me too Stu…me too…
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