Thursday, March 29, 2012

Europa Mission Options

Europa mission concepts under study.  Credit: JPL

At today's Outer Planet Analysis Group (OPAG) meeting, more details of NASA's study of cheaper Europa flagship missions were presented.  The attendees also had a lively discussion of which of three mission concepts NASA should concentrate on for further analysis.

At the last OPAG meeting last Fall, the study team presented a flyby spacecraft that would focus on remote sensing studies requiring power and data hungry instruments and an orbiter that would conduct those studies that could only be done from Europan orbit.  (See this post for a description of the orbiter and multiple-flyby concepts.)  At that meeting, early ideas for a Europa lander were presented.  (See this post for both background on the earlier concept and a description of a high priority location to land at.)

Members of the study team today presented a more mature concept for an Europan lander.  The early ideas included a very simple carrier craft that would deliver two landers into orbit about that moon.  Two landers provided redundancy in case one crashed.  With further analysis, the study team members have concluded that high resolution imaging is needed to find a safe landing site.  Europa is so rough that simple redundancy isn't a viable plan.

The new concept has a much more capable orbiter with a high resolution camera to image the surface at sub-meter resolution (which would put it in the class of the HiRISE camera currently in orbit about Mar).  Images would quickly be acquired of a small number of preselected possible landing sites to find at least one area 100x100 meters that would be flat enough to enable a safe landing.  Advanced precision landing technologies would be used to guide the lander to a landing location as small as a hectare (2.5 acres) and then further analyze that target location during descent to find the safest spot within that location.  Once the lander was safely down, the orbiter would act as a communications relay (although the lander would have its own backup communications capability)

The lander would conduct three types of studies.  It would image the local site to enable scientists to select sampling locations and to understand the processes that created the surface.  A robot arm would drill into the surface to collect samples from as deep as 10 cm to get at ice that had not been altered by Jupiter's intense radiation field.  A mass spectrometer and possibly a Raman spectrometer would be used to analyze the sample composition.  Seismometers and a magnetometer would be used to study Europa's interior by measuring seismic activity and the induced magnetic field created by the subsurface ocean's interaction with Jupiter's magnetosphere.

After the lander concept was presented, the overall study's team leader, Bob Pappalardo of JPL, presented the wrap up.  The two key slides were the estimated cost and risk of each concept and a checklist of questions that each of the concept missions could address about Europa. 

The estimated costs of each mission, not including a launch vehicle that would add approximately $275M to the total, were:

     Europa orbiter - $1.6B (low risk)
     Europa multiple-flyby - $1.9B (low risk)
     Europa lander - $2.8B-$3.5B (high risk)

The multiple flyby craft's higher cost compared to the orbiter results from both requiring more capable instruments and spacecraft systems and from the much longer mission duration creating higher operating costs.  A group at Aerospace Corporation did independent costs analyses for the orbiter and multiple-flyby missions and came up with similar estimated costs.

They study team recognized that at best NASA will at some future time go forward with only one of these concepts.  None would answer all the high priority questions by itself.  For example, characterizing Europa's ocean and its interface with the overlying ice shell and underlying rocky core requires either the orbiter or the lander.  Understanding the structure and composition of the ice shell would require either the heavy, data hungry instruments of the flyby craft for global studies or the lander to characterize conditions at one location.

The meeting attendees spent almost an hour discussing which of these missions they believe would provide the greatest advance in the study of Europa.  No clear answer emerged, in part because OPAG is chartered by NASA to analyze plans and proposals but not to provide advice.  (Note: It's not clear to me how you can cleanly separate the two.)   Pappalardo stated that he felt that the multiple-flyby spacecraft would provide the most Europa science for the dollar.  Most of the participants also seemed to lean towards the multiple-flyby option as their preference.  (While it was not discussed, the multiple-flyby spacecraft with its highly capable remote sensing instruments also should be better able to study Jupiter and the other moons than the less capable instruments planned for the orbiter.)

Examples of a possible set of flyby ground tracks at Europa for the multiple-flyby spacecraft.  Credit: JPL

Editorial Thoughts: The study team has shown that there are two small Flagship (<$2B) class missions that are low risk that could start development without additional technology development.  This is in sharp contrast the previously planned Jupiter Europa Orbiter with its >$4B estimate.  Various strategies such as using solar panels instead of plutonium power supplies or international collaboration might reduce the cost to NASA for either the orbiter or multiple-flyby missions.

The studies also show that viable mission concepts are outside the $1B budget cap of the New Frontiers program.  This isn't surprising.  The Juno New Frontiers mission that is en route to orbit Jupiter has a cost of $1.1B.  The proposed European JUICE Ganymede orbiter (which would also flyby Europa and Callisto) would have a cost of at least $1.3B.  (I've read that ESA increased the cost caps for its Large mission proposals, but don't know by how much.)  Other studies have found similar costs for minimal Titan and Europan missions.  The outer planets are expensive to reach and study.

Unfortunately, NASA's projected budgets do not include beginning funding for any planetary flagship missions until at least the end of this decade.   We remain dependent on the selection of the Discovery Titan TiME lake probe and/or the European JUICE proposals to continue the exploration of the outer solar system once the Cassini and Juno missions end in 2017. 

In the meantime, I hope that NASA will select one of the Europa mission options for continued low level study so that when the budget situation eventually improves, it can be ready to begin development.

Monday, March 26, 2012

India and China Step Up

Artist's concepts for the joint Indian-Russian Chandrayaan-2 spacecraft stack and the Indian rover planned for the mission

This past week, India formally proposed to fund its first Mars mission to be launched next year.  News reports have also stated that China is planning its own, independent Mars mission with a launch date as early as 2013.  Both nations have successfully delivered and operated spacecraft to lunar orbit.  Mars missions will demonstrate a new level of technical competence.
Artist concept for the Chinese sample return lander and ascent vehicle

Both nations also have plans to continue their lunar exploration.  China’s are more ambitious, with a planned lander that will also deliver a 100 kilogram rover to the surface next year.  (The Opportunity rover currently on Mars weighs 185 kilograms.)  That mission would be followed by one that will return up to 2 kilograms of lunar soil to Earth.  This mission would be technically ambitious with an ascent vehicle transferring the sample canister to an orbiting craft that would then return the entry capsule to Earth. 

India also plans a 15 kilogram lunar rover as part of a joint mission with Russia in which the latter will supply the landing vehicle to explore the surface near the lunar south pole.  The date for this mission has been pushed back from 2014 to 2016 because of design difficulties with the Russian lander following the failure of the Russian Phobos-Grunt mission.  (The news reports that discussed Russia indefinitely delaying its planetary missions except for the joint ExoMars missions with ESA did not mention the status of the joint mission with India.)  India will also provide an orbiter for the mission.

Little information is available for most of these missions (at least that I can find on the web using English language searches).  For example, we know that the Indian Martian spacecraft will have an elliptical orbit and will carry up to 25 kilograms of instruments.  India has released more information on its lunar lander mission, Chandrayaan-2, including a list of two instruments for the rover and five instruments for the orbiter. 

Editorial Thoughts:  In the past, the sophistication of planetary missions was often constrained by the availability of technology.  China and India are fortunate to be entering the planetary exploration game at a time when advanced technologies allow them to plan an ambitious series of missions in their first decade of lunar and planetary exploration.  Both countries have excellent engineering skills.  These early missions will give them the experience to plan even more ambitious missions in the following decade.  China’s proposed lunar sample return would be particularly ambitious, requiring a lander, ascent vehicle, orbiter that can rendezvous with the ascent vehicle, and an Earth return capsule that can withstand high speed re-entry.  With these technologies, China could mount sample return missions from asteroids, comets, or the moons of Mars.  Many of these capabilities would also be useful for a Mars sample return, although China would need to develop a Martian landing system (reasonably hard for a payload that would include a return rocket) and the rocket that could ascend from the Martian surface to orbit (hard).

I am confused by the press accounts that announced funding for India’s Mars mission and give the launch date as 2013.  I don’t see how a mission can be architected, designed, built, and tested in that time.  Perhaps considerable engineering work has already been done?  If any of you know more, please leave a comment.

Aviation Week update on India's lunar and Mars mission plans
India’s Chandrayaan-2  

Wednesday, March 21, 2012

A Surprising Admission

In past years, I have tried to keep discussions of budgets to a minimum in this blog.  While this is a nerdy admission of my own (but not the one that is the subject of this post), I find budgets fascinating.  In my past life of planning product roadmaps for a high tech company, I learned to focus on budgets.  They were either an enabler for the projects I wanted to see done or a roadblock.  That is also true for each space agency’s planetary exploration roadmap.  (One senior planetary scientist once said he used to skip the project organization charts for proposed missions; now they are what gets most of his attention because who is on the team enables what can be done.)

However, I recognize that few others share this interest in budgets.  I had planned to have one or two posts when the President proposed NASA’s FY13 budget and then maybe another one next Fall when Congress passed the final version.  This year, of course, NASA’s proposed planetary budget was a nasty shock for the planetary community and those who follow it. 

The “good” news is that the story continues.  Instead of fading into obscurity, Congress and the planetary community continue to express their unhappiness with the proposed plan.  (I wish that were also true for the cuts proposed for ecological science where I do my professional research.  Things could get ugly for the Kane family budget in a couple of years when my current projects complete.)  Congress, of course, can restore part or all of the planetary program budget cuts.

Today, two events occurred that received a fair amount of press.  First, at the Lunar and Planetary Science Conference, NASA’s science managers discussed the budget cuts with the science community.  (As is their job, they defended the proposed plan.)  NadiaDrake at Science News has a nice summary of the discussion as does Paul Rincon at the BBC.

However, the surprising admission came from NASA’s head, Charlie Bolden, at testimony before Congress, where he was grilled about the proposed cuts in a “heated” discussion with key Congressmen.  Here is how Space Policy Online described the admission: “[Congressman] Schiff assiduously attempted to get Bolden to say that the Mars cuts were imposed on NASA by the Office of Management and Budget (OMB), but Bolden insisted the decision was his.   He also admitted that he had not known that the 2016 and 2018 missions with ESA would not actually have returned a sample to Earth.   The 2018 mission only would have collected and stored (cached) samples, but could not return them to Earth -- a hugely expensive proposition.   Bolden said that everyone apparently knew that but him.  He made the same admission at the NASA Advisory Council (NAC) Science Committee meeting two weeks ago where he revealed that he had a long conversation with then OMB Director (now White House Chief of Staff) Jack Lew while under the misimpression that the 2016 and 2018 missions would return a sample, an effort that would indeed have significant budget implications.”

Editorial Thoughts:  I did find it surprising that the head of NASA decided to kill a major mission and leave NASA’s premier partner, the European Space Agency, in the lurch by cancelling NASA’s participation in the ExoMars program.  As I thought about it more, however, I was less surprised.  From Bolden’s point of view, NASA’s science program works well, with the exception of the James Webb Space Telescope’s budget, which suffered galloping cost overruns.  I don’t follow the human spaceflight program in detail, but my impression is that it’s confused and underfunded.  NASA is attempting to simultaneously develop two new human spaceflight systems, one in house and one through commercial companies.  The problems are on the human spaceflight side, and that likely gets almost all of Bolden’s attention.

I also, as I’ve relooked at the budget proposal, I believe that the majority of the cut to planetary program is going to help fund the human spaceflight program (with the rest, about a third, going to fund cost overruns on JWST).  This thought isn’t original with me – I saw it first in some pointed questions in a Congressional hearing that essentially stated the same.  The BBC article mention earlier states, "The FY2013 budget proposal shifts funds to human spaceflight and space technology, in line with the agency's major commitments going forward to fund the development of a huge new rocket and capsule system to take astronauts beyond low-Earth orbit to destinations such as the Moon and asteroids."

As I’ve said before, it’s my guess that Congress will restore some but not all of the proposed cuts by making cuts elsewhere at NASA.  Say that the planetary program gets half the cut back, around $150M.  (Over five years, that would pay for a Discovery mission, including the launch, with some left over.)  What does NASA do with the additional money?  The chance to participate in the ExoMars program has left the building, so to speak.  There’s no alternative Mars or outer planets mission that I know of ready to take that level of funding starting next year.  Planetary missions have long lead times of analysis before they begin development where the serious money is spent. 

My thought: NASA will select one Discovery mission late this spring from three candidate missions.  If Congress restores funds, then perhaps NASA could select a second Discovery mission next year from among these candidates.  Each of the three candidate missions would be ready to begin development almost immediately.  (Beginning a new round of competition for a new list of candidates would require around two years before the selected mission could begin development.) 

I don’t know if this is possible (there are likely peak funding issues), but it would address what to me is the biggest loss in the proposed planetary cuts.  The bedrock of the planetary program, per the recommendations of the Decadal Survey, is a vigorous Discovery program.  With the cuts, the flight rate drops from the recommended five missions per decade to something like two to refund a Mars program later this decade that is currently undefined and not oriented around returning samples to Earth.

While the cuts to NASA’s Mars program have received the bulk of the attention in the press and in Congressional hearings (at least as reported by the press), that is only half the story.  The key question to me is how to use the funding eventually approved by Congress to implement the most balanced program possible that addresses the science community’s highest priority questions.

And I promise that the next post won't be on the budget.

Friday, March 16, 2012

Russian Pull Back?

Conflicting news reports in the Russian media state that Russia's space agency has either cancelled or postponed plans for future planetary missions (except apparently the joint ExoMars mission with ESA).  These missions include the Venera-D Venus lander and orbiter as well as a number of other missions (for example, to Mercury).  No specific reason is given, although one article makes the point that the decision has come after the failure of the Phobos-Grunt mission to return samples from the Martian moon Phobos.

The following two links are Google translations of Russian sites; as the translated titles suggest, the translation can be choppy but generally can be followed:

Federal Space Agency chose "Arctic" Venus and Mercury
Federal Space Agency does not intend to turn off research projects, provided the PCF

My thanks to machi at the Unmanned Spaceflight Forum for the links.

Editorial Thoughts: This cancellation or indefinite postponment is disappointing but not unexpected after the Phobos-Grunt failure.  There were a number of missions on the Russian wishlist, more than either the better funded NASA or ESA programs could had carried out.  Plans for the Venera-D mission appear to have been reasonably far along.  I am disappointed by the loss of this mission, since it would have been the only chance for a landing on Venus this decade.

You may have noticed much more limited coverage of the Russian, Chinese, and Indian planetary programs in my blog than for the US, European, and Japanese programs.  All space programs have long wish lists of missions.  I've learned which sources to use to distinguish the approved and likely missions from the latter group of space agencies but not from the former group.  For example, a friend has forwarded me a presentation on Chinese plans for planetary exploration that include some very likely near term lunar missions and some missions that are at best years away including a Martian sample return.  While the Chinese may end up being the first to return samples from Mars, they (and everyone else) currently lack the technology to conduct the mission.  I can't see such a mission before the second half of the next decade, which puts its in the indefinite future after several changes in government leadership and several economic cycles.

I categorize future plans for planetary missions into three categories:

  • Missions approved and funded by the appropriate political systems (usually national governments but a set of national governements in the case of ESA)
  • Missions firmly on the roadmap of a space agency for which it has concrete plans to develop needed technologies and to request formal approval and funding.  I include in this category missions that are in competition for selection through a competitive program such as NASA's Discovery program or ESA's Large science mission program.
  • Missions an agency would someday like to fly and include on their long term roadmaps to serve as guides in their planning and technology development.  Approval is well beyond the current planning horizon.

In general, I focus on missions in the first two categories, although I occassionally discuss an interesting mission concept.  (And sometimes missions can't be neatly categorized: NASA is "committed" to a Mars sample return mission and to a Europa mission, although their approval is always just over the planning horizon.)  My less extensive coverage of the programs of Russia, China, and India reflect my more limited ability to distinguish likely missions from wish lists.  If any of you can point me towards good sources of information, I'd be most grateful.

ExoMars and NASA Budget Updates

The European Space Agency's new joint ExoMars with Russia has been approved to proceed by the agency's ruling council.  The new program includes a 2016 orbiter and at least one lander and the 2018 ExoMars rover.  Russia will provide launch vehicles for both missions and instruments.  Russia will also provide a nuclear power source for the demonstration lander, allowing it to operate for at least months on the Martian surface.  The 2016 orbiter will still include instruments to study trace gases in the atmosphere including methane.

The new plan follows NASA's withdrawal from the program, resulting in the loss of NASA's landing expertise.  As a result, ESA will fly a demonstration lander to develop and prove its own landing technology in 2016.  Presumably this lander will provide the basis for the 2018 rover landing system.

Total cost of the two missions for ESA is expected to grow from 1B euros to 1.2B euros, of which only 850M euros have been committed by ESA's member states.  The ruling council has stated that ExoMars is a top priority.  Different press accounts suggest that the additional funds may be sought from the member states (which are already being requested for additonal funding for other programs) or from elsewhere in the science budget.  The Space News account suggest that ESA may forgo its proposed next large (~1B euro) science mission since NASA has declined to participate and help fund all three missions in competition.  (One of those proposals would be for a Ganymede orbiter/Europa-Callisto flyby mission.)

Editorial Thoughts:  Today's press accounts leave many details unclear.  Previous accounts, for example, have talked about the Russians providing additional landers beyond ESA's demonstration lander.  There are also no specifics on which instruments will be carried by the 2016 orbiter or the demonstration lander.  (Maybe, finally, a capable seismometer will be delivered to the Martian surface now that the demonstration lander will have a long lived power source?  In this case, depending on the fate of the proposed Discovery InSight mission, the ExoMars lander might either partially replace or supplement the InSight lander's capabilities.)

I have always felt that the ExoMars missions are important to continuing the exploration of Mars.  Methane in the Martian atmosphere is a mystery, both as to whether it is really there (data suggests, probably) and its source locations and orgins (geochemical or biological).  The rover will search for organics on the surface at a second location after NASA's Mars Science Laboratory and will analyze samples gathered from up to two meters below the harsh surface.

Europe Joins Russia on Robotic ExoMars (Aviation Week) 
Europe still keen on Mars missions (BBC) 
ESA Ruling Council OKs ExoMars Funding (Space News) 


On the other side of the Atlantic, the proposed cuts to NASA's planetary program are creating more of a ruckus than I remember for any science program since the cancellation of the super collider.  Press accounts of the dispute are common, including a substantial piece in the New York Times.  Key Congressmen have sharply questioned NASA's management over the proposed cuts and have blocked the administration's proposed cuts to the planetary program for the current budget year.  (In the US, approved budgets are the law of the land and cannot be changed by the administration without approval by the appropriate Congressional committees.  It is common when a new budget proposal seeks a new direction for the adminstration to ask for and receive permission to reallocated current funding to reflect the expected change.  In this case, the Congressional committees refused permission saying that changes of this magnitude should be fully debated in Congress first.)

Press accounts suggest that the key tradeoff in Congressional deliberations will be between funding for commercial manned spaceflight systems and planetary exploration.  The adminstration proposed substantial increases for the former and cuts for the latter.  Congress' priorities appear to be the reverse, suggesting a heated debate between the two branches of government.

Appropriators Blocking Mars Mission Move (Aviation Week) 
Life on Mars? Funds to Find Answer Fade (New York Times)