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The Planetary Society Blog

By Emily Lakdawalla


Welcome to The Planetary Society's Blog, a guide to interesting stuff going on in space science, space exploration, and space advocacy. Have any comments?

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Oct. 10, 2008 | 14:21 PDT | 21:21 UTC

MSL is still on target for a 2009 launch, no matter what anybody says


Last week an article in Aviation Week inspired rampant speculation about the fate of the next Mars rover mission, MSL, which is scheduled to launch in 2009. The article suggested that after a NASA Headquarters review being held today, Friday October 10, 2008, that the schedule could be so tight that they'd delay until 2011, or that budget overruns could be so great that Congress could choose to cancel the mission.

In response to this speculation, NASA held a press briefing today after the meetings, and the main message was pretty brief: The plan for MSL's development is to "continue unabated toward launch in 2009," said Doug McCuistion, director of the Mars Exploration Program. Despite ongoing budget and schedule "challenges," they seem to have reasonable confidence that they can meet the target launch date. So that's good news.

Mars Science Laboratory
Mars Science Laboratory
Credit: NASA / JPL
However, regardless of whether MSL sticks to its 2009 launch date or delays to 2011, it's going to cost more money. Originally budgeted at $1.6 billion, the cost has ballooned to $1.9 billion, and rumors suggest that JPL will need another $100 to $200 million on top of that to bring MSL to launch. A launch delay would cost another $300 million. However, the NASA officials would not go on record to state any of these numbers. McCuistion said, in response to repeated pressure from the members of the press, "We can't say where the money is going to come from yet because we haven't fully resolved that yet. We have to work this with the Office of Management and Budget and Capitol Hill before we finalize that." And, of course, until they officially say how much it's going to cost, they can't officially say where the money is going to come from: "Until we finalize that we can't discuss the sources."

Associate Administrator Ed Weiler did say this about where the money would come from: "We'll work within the Mars program first. If we can't find enough money there, the planetary program next. But before blindly canceling or delaying [missions], we look at other opportunities." For instance, he said, some missions don't spend all their money in a given year, carrying some over until next year; MSL could gobble that up. "There are certain accounting things you can do which can minimize the impact to missions. Not knowing the exact number [that MSL will need], I don't know if we can avoid hits to other missions, but that would be my first goal. As far as continuing the mission, Congress has always been very supportive. I can't tell you how many times Hubble ran into problems. If we made the easy decision to cancel, we'd've never launched Hubble, never launched Cassini, and a few others. MSL is a flagship mission in the Mars program, and as long as we think we have a good chance to make it we're going to do what we have to do."

Now, I don't believe for a minute that Weiler doesn't have good estimates of what they think it'll cost to solve all the problems MSL has now. I suppose, though, you still have to ask if there are yet more problems that may come down the pike. He doesn't want to have to go shopping for funds more than once if he can help it. There's a lot of speculation about where the funds could come from. If he's serious about sticking within the Mars program, there's really only one place to grab hundreds of millions of dollars from, and that's the recently approved MAVEN orbiter. Other people are speculating that they could go outside the Mars program and grab money from GRAIL or LADEE, lunar missions, or Juno, the next Jupiter mission. One reporter asked if they could choose to take money from the next outer planets flagship mission, and at least there was a reassuring answer to that one: although the next outer planets flagship will be, in the end, a two-billion-dollar mission, there's not very much money for it in fiscal year 2009, so that wouldn't be a place that could be robbed to fix the MSL budget.

Nested wheels
Nested wheels
Comparison of three sets of rover wheels for Mars: Sojourner (smallest), the Mars Exploration Rovers (middle), and the Mars Science Laboratory (largest). Bigger wheels need much more robust motors. Credit: NASA / JPL
What's the nature of the problems? As with all flagship missions, MSL is trying to do something that hasn't been done before -- put an instrument payload the size of Viking's on wheels -- so it's impossible to anticipate all the problems. And MSL has had its share of them, for sure. The biggest problem it has is its actuators -- the motors that move the joints in its arm, in the sample handling mechanism, and the wrist joints in the wheels. Originally, one of the ways they were going to make MSL robust to low temperatures were to use actuators that had a dry lubricant, which could operate at pretty much any temperature.

Unfortunately, the development of that dry lubricant failed, so they had to start over with the actuator design using a wet lubricant, the same as Spirit and Opportunity. (This happened a long time ago.) That means the actuators need to incorporate heaters, to prevent the lubricant from freezing at Mars temperatures, which also imposes a big hit to the power budget for the mission. And they couldn't just be scaled up from Spirit and Opportunity -- MSL is just so massive that the actuators have to be much more robust. They mentioned at today's briefing that the original design had titanium gears. The titanium gears proved unable to handle the stresses, so they had to switch to stainless steel. It's been one thing after another, and because actuators are important elements of so many parts of the rover, the fact that they haven't been delivered yet has been holding up the whole assembly process. They even said that JPL has sent staff to the company in New York, Aeroflex, to support the work there. Aeroflex is already working multiple shifts. They expressed hope that the actuators would be delivered at the end of November.

And that's just one of the problem elements. They had problems with parachute design that are now resolved. They found that the ablative material that was used on the Spirit and Opportunity heat shields would melt away in great gobs at the slightly higher speed with which MSL will be coming in, so they had to swtich to a different material -- the same ceramic tile stuff used on the Space Shuttle (and also, incidentally, used on the Stardust and Genesis return capsules). Some instrument development is late. They're still working out problems with the sample handling mechanism on the arm that will deliver samples to the chemistry labs. The new radar system for the landing cost more than they anticipated. None of these is unsolvable, but they all impose hits to both budget and schedule.

The MSL 'scarecrow'
The MSL "scarecrow"
At the opening of the newly remodeled Mars Yard at the Jet Propulsion Laboratory on June 19, 2007, the "scarecrow" model of Mars Science Laboratory (so named because it "has no brain") is put through its paces. It was demonstrated to have no difficulty climbing meter-sized boulders, but to avoid risk the actual rover will not be driven over rocks taller than its wheels while on Mars. Credit: Emily Lakdawalla
Of course, it's frustrating that flagship missions always, ALWAYS, go waaayyyy over budget. One of the reporters asked that question -- can't we do something to prevent these budget problems from always coming up? McCuistion gave a good answer to this one -- he said that yes, there is a way: that the thing to do is to spend more resources, outside of individual mission budgets, to develop the new enabling technologies that missions depend on. For instance, that dry lubricant problem is one that is important in space in general, and might have been handled through a separate technology development program, rather than being folded in to the MSL budget. That wouldn't necessarily have made the dry lubricant development work any better, but at least it wouldn't have been a big factor in imposing schedule delays (and therefore budget hits) on a whole big flagship mission.

In the end, the scientists and engineers I've talked with about MSL are pretty positive about its development right now. At the last landing site selection meeting in October of 2007, there seemed to be a lot of hand-wringing and worry going on. This time around, although there was still worry about money, there was a sense that a lot of the problems that had been nagging people last year had been solved. And the assembly is proceeding -- the cruise stage is nearly done, the descent stage nearly complete, the rover nearly assembled (except for those pesky actuators), two of the instruments (MARDI and DAN) are delivered and one of them, MARDI, already integrated; the mission is really taking shape, and now they're getting ready to stack everything together and start the environmental testing. There's a lot of work to do, but people seem to think it can be done.

The next one of these high-level Headquarters reviews happens in January. By then, the actuators should have been delivered, and also most of the instruments. Perhaps more importantly, the outcome of the presidential election will be known, and we may also then have a better handle on whether the current meltdown in world financial markets will cause the next president to make massive cuts in discretionary spending like NASA. Hopefully there will be no new problems before then, and MSL will get green-lighted for its launch next year, during a launch period that stretches from September 15 to October 15.



Oct. 10, 2008 | 11:46 PDT | 18:46 UTC

Carnival of Space #74


Go visit the bluegrass state for the 74th carnival of space!

Also, this week's Planetary Radio features Roger Buick, who struggles to find fossils from Earth's earliest history and considers the challenges of finding them on Mars.

And Lou Friedman wrote recently about seeing the universe from Hawai'i.



Oct. 10, 2008 | 10:03 PDT | 17:03 UTC

Images of the 2008 TC3 fireball from space!


It seems that no one in Sudan was able to record the 2008 TC3 fireball; the only image I've seen that was shot from the ground was one very tiny pixel in the sky seen from a beach in Egypt. But in this day and age, there are always eyes in the sky on practically every point on Earth, and, through good fortune, the METEOSAT-8 spacecraft scanned the globe at the moment that the asteroid was putting on its show.

First, a little context: the METEOSAT satellites are geostationary weather satellites operated by a European consortium called EUMETSAT. The METEOSATs are among the whole-Earth-observing spacecraft I list on my "Whole-Earth views from Geostationary Satellites" web page. METEOSAT-8 was launched in August 28, 2002. In April of last year, it was relegated to backup status, replaced in active status by METEOSAT-9; both orbit Earth in a geostationary position near about 9°E, which puts all of Africa and Europe in view. As of May 13, 2008, EUMETSAT started using METEOSAT-8 in a "rapid scanning" mode, in which it scans the globe once every five minutes. So it was well positioned to spot the fiery atmospheric entry of 2008 TC3.

Okay, so here's the view of the fireball as seen through an infrared instrument on METEOSAT-8, which records the temperature of the surfaces it scans. The temperature scale on the right is in Kelvin; 273 Kelvin corresponds to 0 Celsius. Most of the land in this desert region of Earth is quite warm, with a few cold clouds to the southwest. And then there's the orange flare of the fireball.
METEOSAT-8 catches the 2008 TC3 fireball
METEOSAT-8 catches the 2008 TC3 fireball
At 02:45:47 UTC on October 7, 2008, the first near-Earth asteroid to have been discovered before it hit Earth entered the atmosphere over northern Sudan. The flare of heat given off by the asteroid's passage through the atmosphere was recorded by the geostationary weather satellite METEOSAT-8. Credit: EUMETSAT
But wait, there's more fun to be had with this data set. EUMETSAT released more data, taken in visible wavelengths. There's a flash there too.
Image of the 2008 TC3 impact flash from METEOSAT-8
Image of the 2008 TC3 impact flash from METEOSAT-8
This view of the asteroid 2008 TC3 entering the atmosphere shows the visible-light flash associated with the entry. Credit: EUMETSAT
But if you put the two images together, visible (flash) and infrared (heat), something funny happens. The two don't line up! The peak temperatures recorded by METEOSAT-8 are about 23 kilometers (14 miles) east-southeast of the brightest flash.
Offset visible and infrared flashes from asteroid 2008 TC3
Offset visible and infrared flashes from asteroid 2008 TC3
METEOSAT-8 recorded both the visible light flash and the peak temperatures of the fiery entry of asteroid 2008 TC3 into the atmosphere over northern Sudan. Oddly, the two signatures are offset: the peak temperatures are about 23 kilometers (14 miles) east-southeast of the impact flash. Credit: EUMETSAT
The EUMETSAT page said that the entry velocity was 12.8 kilometers per second, so, without allowing for deceleration, that represents about 2 seconds' difference along the asteroid's path. (I don't know how much deceleration to allow for.) Two seconds isn't very much, but I'm at a loss to explain why the peak heating and peak flash would be so offset from each other within one satellite observation; maybe it just means that the two instruments weren't scanning quite simultaneously. I don't know enough about how the METEOSATs work to be sure.



Oct. 9, 2008 | 14:40 PDT | 21:40 UTC

Catching up with Phoenix to sol 133: Digging at La Mancha, grabbing Galloping Hessians from Pet Donkey


Don't blame me for the names. I'm just the messenger. There's been a fury of digging lately on Phoenix, and that means a flurry of new names to figure out. When I last mapped out the work volume (the area within reach of the robotic arm), this is what it looked like:
The Phoenix 'work volume' as of sol 96
The Phoenix "work volume" as of sol 96
Pink text indicates the approximate locations of samples delivered to MECA, and green text indicates samples delivered to TEGA. Small gray text indicates named rocks. The base panorama consists of images captured on sol 84. Credit: NASA / JPL / UA / Texas A & M / mosaic by James Canvin / map by Emily Lakdawalla
Since sol 117 -- which was the day that Phoenix moved the rock named Headless aside, scooping it forward into the trench called Neverland -- there's been a boatload of digging and sample deliveries, as the Phoenix team tries to make the most of their little remaining time. Here's a quick look at how the work volume appeared as of just two sols ago.
Panorama across the Phoenix work volume, sol 131
Panorama across the Phoenix work volume, sol 131
Phoenix took this six-image panorama across the upper part of its work volume on sol 131. It documents the locations of two new trenches, in the center of the work volume, named La Mancha and Pet Donkey. Other relatively recent changes are a new dump pile, Bee Tree, to the right of center at the top. Between Bee Tree and Croquet Grounds (the dump pile at extreme right) is a new divot in the soil, where the sample called Rosy Red N was collected. Credit: NASA / JPL / UA / Texas A & M
With the new digging comes a pile of new names. Here's my best attempt at putting those names on my work volume map. It's even more cluttered than before because I've also added, in yellow, the locations of all the samples that have been delivered to the Optical Microscope.
The Phoenix 'work volume' as of sol 130
The Phoenix "work volume" as of sol 130
Pink text indicates the approximate locations of samples delivered to MECA's Wet Chemistry Laboratory (WCL); yellow text, samples delivered to the Optical Microscope (OM); and green text indicates samples delivered to TEGA. Small gray text indicates named rocks and dump piles. The base panorama consists of images captured on sol 84.

The deliveries happened according to the following schedule:
Sol 12: Baby Bear to TEGA 4 (in oven sol 16)
Sol 17: Mama Bear to OM
Sol 26: Rosy Red to OM
Sol 30: Rosy Red to WCL 0
Sol 38: Sorceress to OM
Sol 41: Sorceress to WCL 1
Sol 64: Wicked Witch to TEGA 0
Sol 67: Mother Goose to OM
Sol 72: Rosy Red 3 to TEGA 5
Sol 75: Wicked Witch to OM
Sol 85: Burning Coals to TEGA 7
Sol 96: Golden Goose to WCL 3
Sol 99: Golden Key to OM
Sol 101: Golden Goose to OM
Sol 102: Golden Goose to WCL 3 (2nd attempt)
Sol 107: Sorceress to WCL 2
Sol 110: Golden Goose to OM
Sol 113: ??? to TEGA
Sol 120: Sam McGee to TEGA 1
Sol 126: Wicked Witch 2 to TEGA 1
Sol 128: Galloping Hessian to OM
Sol 131: Rosy Red N to TEGA 6
Credit: NASA / JPL / UA / Texas A & M / mosaic by James Canvin / map by Emily Lakdawalla
There remains only one unopened oven on TEGA. The mission says that they'll probably have to quit using the arm by the end of this month.

Check out the Robotic Arm Camera raw images page; there's lots of new images there, including several attempts to record dust devil movies (I didn't have time to check if they were successful in catching any on camera). And the sol-by-sol summary is now up-to-date as of sol 133.




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