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A Farewell from the Southern California Selene Group

SCSG — Sat, 24 May 2008 13:32:12 -0700

For us, the fun part is over. We have had a wonderful team, and we’ve all worked closely together to come up with an innovative, lightweight and low-cost spacecraft design. It has been a really good five months.

The Team Summit’s Guidelines workshop showed that the more bureaucratic part of the mission has begun. While on a personal level, I liked each of the leaders there from XPF, and enjoyed interacting with them, I was puzzled at the somewhat cavalier way they seemed to dismiss some of the teams’ concerns. For example, we were very proud of the fact that our team had managed to get some surplus company fuel tanks; when I asked about it, without much thought I was told “you’ll have to get a ruling on that.” Also, when I asked something about our camera design (a design we had worked very hard on), I was told that the way we were doing it would not be allowed.

HUH? Do they know how hard we have worked on this?

I inwardly cringed at their responses to some of the other team’s concerns. The delightful FredNet team. Those innovative and very impressive ARCA guys (who had lugged across Europe a full-scale mockup of their craft to ISU for display!). Colleen (Astrobotics), Paul (Quantum3), Mary (LunaTrex) – they all had concerns regarding the media aspects of the rules that I did not feel were adequately addressed, and maybe even more important -- even adequately appreciated.

The cumulative effect coming from the XPF leadership was one of discouragement, rather than encouragement.

I had a sudden moment of clarity when I realized that even if we could make it through our enormous hurdles of getting a suitable launch vehicle, and even if we could get a sponsor, for the reasons stated here and in my previous blog, I no longer even wanted to win this prize!!

When I discussed all this later with our team leader Harold Rosen, he agreed completely. He is far too independent, and far too smart, to waste any more time in pursuing what he now knows to be a different goal (an “outrageously unrealistic version of space commercialization,” to use his words) than what he had originally thought (a simple contest to see who could get to the moon first and send back the required Mooncasts). As he said to me, he’s got more important things to work on…!

I will miss interacting with Will Pomerantz and Becky Ramsey of the X PRIZE Foundation. Those two were absolutely fantastic in every way, very encouraging, and I admire and like them very much.

But we are OUT. Good-bye to all, and best of luck to all the other teams.

Deborah Castleman

Some serious thinking at the Southern California Selene Group

SCSG — Fri, 23 May 2008 21:15:26 -0700

In my first blog, I wrote why Harold Rosen formed the Southern California Selene Group. In short, he and I registered our team to compete for the Google Lunar X PRIZE to demonstrate that a low-cost space mission to the moon could be accomplished and could lead to lowering the cost of some future robotic missions to planetary moons. Plus, we intended to have fun! Harold and I both are strong supporters of space science and robotic space exploration. (For one, I’m an astronomy and cosmology enthusiast.) We love the kind of work that JPL is doing, for example. But we most definitely are not in favor of human space missions. That is not our goal, nor do we support such a goal.

The Team Summit turned out to be a real wakeup call. In the Guidelines workshop that I attended just last Tuesday, the cumulative effect of hearing all day from Peter Diamandis, Bob Weiss and Gregg Maryniak that the “real purpose” of the Google Lunar X PRIZE was to promote the so-called commercialization of space (which I took to mean highly impractical stuff like mining the moon and beaming power to the earth, as shown in one of GLXP kickoff videos), humanity’s future in space, etc. etc., took its toll. I couldn’t help but think “what am I doing here?” When I spoke to Harold about it on the phone later, he agreed – no way did he want to be involved in promoting a goal he does not believe in.

As I stated in my short speech at the media event on Wednesday (you can see it on the webcast), we already face serious issues regarding rising projected launch costs, which complicate the already-difficult task of obtaining a sponsor… so we have some serious thinking to do.

Deborah Castleman
Associate Team Leader

Camera and Propulsion System Design at the Southern California Selene Group

SCSG — Mon, 28 Apr 2008 16:05:13 -0700

The Southern California Selene Group is continuing with its engineering and design work. Since my last blog report, we’ve had two very productive all-hands team meetings on Saturday, March 22 and Saturday, April 19, and we have another scheduled for May 10. (By the way, I’ve just put up a new photo album on our team page, showing pictures from our last three team meetings.) In between, as always, there are lots of smaller meetings going on – for example, at least once a week, Harold meets with Ron, Dorian, Robert, Al, Brian, Dan and others to go over key design issues.

Also, I’d like to mention that Harold’s brother Ben Rosen (former venture capitalist) has a blog, where he wrote a humorous and clever post about Harold’s pursuit of the Google Lunar X PRIZE. You can read the blog at: http://benrosen.com. The title of the blog post is “Spin Me to the Moon” dated 25 March 2008.

We are happy to announce the addition of three new team members: Phil Donatelli (he was just advising us before), Daniel Geng and Patty Pun. Their impressive bios can be read on our team web pages. We also have a new honorary member, six year old Lucas.

OUR HONORARY MEMBER. Lucas came to us by way of his mother Courtney, who contacted the X PRIZE Foundation, writing that her six year old son had a design for a moon rover, and asked if someone there could forward her letter to our team. Will Pomerantz did just that. To make a long story short, after much back-and-forth correspondence, we were finally able to meet with Lucas and his mother -- both delightful people. Lucas brought along the paper that had his rover design. Once he started talking, you could see that this was no ordinary child. He explained to Harold how the solar panels worked, and how the batteries would provide power during the new moon phase. Curious (and amazed!) at his abilities, we asked him lots of questions. It was amazing how much he knew, and seemed to understand. The one that blew us away was when we asked him what caused the seasons (it’s a sad fact that many adults don’t know the answer to this question). He thought for a moment, tilted his head, and said “well, it is due to the angle of the earth…” (!!)

Lucas and his mother Courtney, along with his younger sister Cate (at three, she is too young to join our team:-) stopped by towards the end of our most recent team meeting on April 19. Many of the team members were therefore able to meet Lucas, and interact with him. Al Wittmann discussed with Lucas some of the design decisions we had made at the meeting. Lucas followed what Al was saying closely, and asked relevant questions (often he was gently and unobtrusively guided by his very smart mother). Then, after Lucas mentioned the “Saturn VEE” (of course! why would he know about Roman numerals?), Rex Ridenoure showed him some pictures of rockets, as well as the Saturn V, that he had on his computer. We all enjoyed welcoming our honorary team member.

Now, back to design issues. Major design progress has occurred in two key areas: the camera system, and the propulsion system.

CAMERA SYSTEM AND ELECTRONICS. Harold has been working with Brian Bliss and our new team members Dan Geng and Patty Pun to finalize the electronics and design of our camera system. To meet all the Mooncast requirements, we wanted to create a camera system from commercially available components. We need this camera system to be high up in order to get good viewing (looking downward) of the top of the spacecraft, as well as (looking outward) of the distant lunar surface. So we decided from the start to locate the camera system at the top of the mast – the highest point of our lander. The design challenge was to make this fit within our stringent mass and volume constraints. We have also designed the appropriate mechanisms to provide the pan, tilt and focus adjustments needed to meet the Mooncast requirements. Our detector will be a single focal plane array whose associated electronics provides the versatility for the required self-portrait detailed images, near real time video, and high definition video – meaning, these various specified modes are provided electronically.

We like this simple and elegant design.

PROPULSION SYSTEM. Since my last blog post when I discussed propulsion design issues, we’ve gone through several design iterations regarding our propulsion system. (In fact, before reading further, you might want to re-read that blog post to review the issues involved.) We have now converged on a configuration that appears optimum: it’s a blowdown bipropellant system, with a hybrid descent system consisting of a solid retro-rocket significantly augmented by liquid propulsion thrusters.

Of course, the selection of this configuration is contingent on the timely availability (we don’t yet have complete data from the manufacturers) of the requisite thrusters and the particular solid rocket we have in mind. Also, this configuration has a slightly higher center of mass, and we haven’t yet been able to confirm its compatibility with this particular still-unpublished Falcon 1e launch vehicle requirement. With these caveats in mind, let me explain how we got to this choice.

SpaceX recently issued its new Falcon Lunar Capability Guide, and this proved to be good news for us, since the Falcon 1e is now shown to provide a higher mass capability into low Earth orbit. This affects the design decision of bipropellant vs. monopropellant. We had wanted to go with a bipropellant before because of the potential performance improvements provided by its higher specific impulse, but the original lower mass capability advertised for the Falcon 1e made this problematic. This is because the dry mass of the bipropellant system is much higher than that of a monopropellant system and, under the original constraints, that factor outweighed its specific impulse advantage. With the new numbers for the Falcon 1e, the balance has shifted. Our spacecraft design now readily accommodates the use of a bipropellant system.

The blowdown system has long been desired by us for its relative simplicity, but it necessarily occupies more volume. We looked carefully at this, but couldn’t fit it into our volume constraints if we used an all-liquid blowdown descent system. So we decided to go back and look at re-incorporating the solid retro-rocket. We found that we could do this by using a hybrid descent rocket system – meaning, a system where the solid rocket provides roughly two-thirds of the delta V required for the descent, while the other one-third is provided by the liquid propellant thrusters. This combination results in significantly lower “gravity loss” during the descent phase than was possible with the all-liquid descent system. (“Gravity loss” is the additional delta V required for descent, as compared to an ideal system that has infinite thrust.)

So, with less liquid propellant needed for the descent portion, the blowdown liquid tank volume can be smaller, making for an easier fit. This is great – we can now use the blowdown system.

While we still won’t have a known, fixed mass to decelerate before the solid rocket burns, the fact that after it burns, roughly a third of the delta V required for the descent is provided for by the liquid thrusters means that it is still much more “forgiving” of descent timing errors than our original system had been.

As Harold puts it, this overall combination (a blowdown bipropellant system, with a hybrid descent) provides the best performance, characterized by the “highest landed mass (excluding the propulsion system).”

OTHER MATTERS. Dorian has been in Europe for most of the month on business-related travel. In addition to all his other team work, Ron Symmes has been working various facilities issues, and since I last wrote, he had arranged for him and Harold to visit three such sites. Ron’s getting it all in place so that we will be ready to start building our spacecraft as soon as we have our funding in place. Well, in truth we will be able to start some construction even before that! We are getting lots of offers of free help. The network of helpful friends and colleagues that Harold and Ron (it seems that Ron knows everyone) have amassed over the years is truly gratifying.

TEAM SUMMIT. I will be representing our team at the Team Summit to be held in Strasbourg on May 20 and 21.

Deborah Castleman
Associate Team Leader

Propulsion system design at the Southern California Selene Group

SCSG — Thu, 20 Mar 2008 10:22:51 -0700

We’ve been busy -- there’s a lot of engineering and design work going on with the Southern California Selene Group. We had a very productive all-hands team meeting on Saturday, March 1st, and we will be having another on Saturday, March 22; meanwhile, there have been lots of smaller meetings going on. Right now, most of our focus is on the electronics (in particular, implementing the landing radar), the propulsion system, and in considering other launch options. To that end, we welcome to our team Stan Kent, who is a propulsion expert. (You can read his bio on our team pages.) Phil Donatelli is also advising us in the propulsion arena. Our project manager, Ron Symmes, in addition to all the design work, has been working on getting us facilities, and in investigating alternative launch options.

Before I write anything else, we all want to express our sadness at the passing of Arthur C. Clarke. Our team leader, Harold Rosen, is the recipient of the 1990 Arthur C. Clarke Award, and a long-time friend. Stan Kent, who also knew Arthur well, is sending a condolence note on behalf of our team. In a preface to his 1992 book, “How the World Was One: Beyond the Global Village,” Arthur wrote: “Dedicated to the real fathers of the communication satellite, John Pierce [Telstar] and Harold Rosen [Syncom], by the Godfather.” Always a sense of humor! I think that I have read all his books, as I am sure many readers of this blog have done as well. Stan has suggested, and we all agree, that we put some kind of memorial words on our lander in honor of him. But perhaps the best honor we can give this pioneer and visionary is to have us – or any one of the teams competing – win the Google Lunar X PRIZE.

With that in mind, here is what we are now doing. I’d like to write here about a potential major design change to our propulsion system, and give you some of the background as to how it came about. Even if we decide against this new system, I think you will find it instructive to see what some of the trade-offs are, and how our team operates.

First, some background. There are two basic types of liquid propulsion systems under consideration here: a monopropellant system (using hydrazine), and a bipropellant system (which uses an oxidizer, nitrogen tetroxide; and a fuel, monomethylhydrazine). A monopropellant system is simpler, and lower in dry mass. A bipropellant system gives a higher specific impulse (For those readers who don’t know what specific impulse is, let’s just say that for a given momentum change (delta V) of the spacecraft, this delta V can be accomplished with a smaller mass of fuel if that fuel has a higher specific impulse – so the higher the specific impulse, the better!) There are also two different types of pressurization systems that can be used: a pressure-regulated system, and a blowdown system. Typically, a blowdown system is used with a monopropellant system, and a pressure-regulated system is used with a bipropellant system.

Our team members are well-versed in all these systems.

Our initial (preliminary) design – you can see this in our system and mission summary -- uses a hydrazine blowdown system, with a solid retro-rocket. Let’s start with the solid retro-rocket. Why was this chosen for our moon lander? Historically, looking back to the 1960s, a solid retro-rocket was used for the Surveyor moon lander. Syncom, as well as subsequent geostationary communication satellites, used a solid rocket apogee motor. Neither Surveyor nor Syncom used hydrazine, because the catalyst didn’t exist at that time – hydrogen peroxide was used for Syncom, and Surveyor used a bipropellant system. So, initially, in line with our “blend of the old and the new” design philosophy, we went with a solid retro-rocket.

Our team’s lead systems engineer, Dorian Challoner, wanted to cover the bases so he asked Robert Rosen to analyze the use of an all-liquid descent system. Dorian couldn’t ignore the fact that a liquid retro-rocket is more forgiving of descent timing errors and its use adds mission flexibility – with its use we may be able to pursue the 5000 meter roaming prize, as well as visit a historical landing site (within our reach is Luna 9, site of the first moon landing in February 1966). Meanwhile, Al Wittmann was dissatisfied from the get-go with our active interstage (an interstage having its own propulsion system). He didn’t like having fuel tanks and thrusters on the interstage because he thought we could incorporate those functions on the lander. But putting these functions on the lander, with the unspecified amount of fuel remaining (because it wouldn’t be jettisoned with the interstage) after the necessary orbital corrections, wouldn’t work well as long as we had a solid retro-rocket, because before firing it is best to have a known, fixed mass to decelerate (because this would establish its burnout altitude), making the vernier descent portion easier. (A caveat: many other team members have worked hard on, and weighed in with, their contributions -- I apologize that there is no room here to mention all aspects of who contributed what, when.)

But going with a all-liquid descent system necessitates the use of a bipropellant system, because the specific impulse of a monopropellant system would be too low for the task. This (potential) design change has a ripple effect on the entire spacecraft design, as well as the timing of mid-course and other corrections. As one example of this, the interstage almost disappears: it is just a simple, cylindrical structure with a perigee motor at one end and the lander at the other end. It has but one active function: it uses small solid rockets to spin the spacecraft up to 50 rpm prior to the perigee burn. Another example is a simplification that Robert recently made. In our original system, we were going to spin up to 50 rpm before the perigee burn, and later to 100 rpm before the retro-rocket firing (in order to improve retro-rocket stability and the final, power-off stage of the touchdown). Robert pointed out that, if we go with this system, the much lower thrust of the touchdown and our new lander gear geometry give adequate stability at 50 rpm – hence, no second set of small solid spin-up rockets would be needed on the interstage.

On top of all this, we’ve also been looking at the tradeoffs between using a pressurize-regulated system versus a blowdown system. The latter, because it requires lots of storage space at low pressures, appears unfavorable at this point because it takes up too much volume (larger or more tanks). And there’s more. I can’t do justice to the complexity of the issues involved here, except to say that these arguments, design iterations, and analyses have been percolating in a stimulating intellectual ferment that is truly a delight to behold (genius at work!). This coming Saturday, we will hash all this out -- with Stan and Phil playing a starring role -- and make our decision.

Deborah Castleman

Associate Team Leader

The Big Elephant in the Room: FUNDING

SCSG — Fri, 29 Feb 2008 11:39:08 -0800

The big elephant in the room is FUNDING. Going to the moon is not cheap! I don’t think that this is a problem with just our team – all the Google Lunar X PRIZE teams likely have this problem. Right now we in the Southern California Selene Group are a self-funded group of volunteers, with extraordinary knowledge and expertise in knowing how to successfully accomplish this space mission (you can read our bios on our team page). Our design is so simple (and elegant!) that the spacecraft could be available for launch in less than two years. (I’ll leave aside the question of launch vehicle availability for the moment.)

Our team’s cost estimate of $20 million is based on real knowledge of the space business -- not wishful thinking. We have a lot of experience with costing out space missions!

This original estimate of $20 million was based on the following: $10 million for the launch vehicle and the solid rocket upper stages; $5 million for the spacecraft (which in our design includes the interstage and the lander/hopper) and a $5 million margin (always a good idea to have a cost margin in a space program!). Since making that estimate, we’ve seen our margin eaten up by a price increase (over what was stated on the SpaceX web site) in the launch vehicle Falcon 1e and a price increase (over what they generally used to cost) in the upper stages (ATK/ Thiokol) – in our design, the perigee rocket and the retro-rocket. Nonetheless, we are still holding fast to our $20 million cost estimate, but our margin is rapidly disappearing.

How to raise $20 million??!! We can’t ask for “investors,” because this money would be spent solely on winning the prize. So we call it “sponsorship.”

We considered trying to raise it piecemeal, in parts, here and there. But frankly, that troubled us. What if someone sponsors us in part, for example, and it turns out that we are unable to raise the rest? We would have to shut down (eventually), and that beloved sponsor’s money would be spent without our getting to the moon.

The only fair way to do this is to find someone out there -- or a group of “someones,” and/or a corporate sponsor -- all at once, who can commit to $20 million. We would love to have such a person/ persons/ corporation join our team, have naming rights, logo placement on the lander, but best of all -- have fun with us, share in the glory and excitement while playing an absolutely crucial, pivotal role on this winning team. Does such an individual (or individuals, or corporation) exist? We like to think so, and we are basing all our efforts on that hope!!

Meanwhile, there is a lot that this self-funded group can do. This past week our project manager, Ron Symmes, has been contacting vendors (tanks, thrusters, solid rockets, etc), arranging for test facilities, and working with Dorian Challoner, our lead systems engineer, on programmatic aspects. John, Al and Robert have been doing detailed analyses and making structural drawings, and our other team members have been busy as well. (Rex Ridenoure, our deputy project manager, has been at a space conference in Denver.) Dr. Rosen had a meeting yesterday with Ron, Dorian, Susan, Robert and Al on spacecraft design issues, and this Saturday (March 1st) we are having an all-hands seven hour team meeting to work first on refining the electronics architecture and design for our lander. This includes the landing radar system; control electronics; telemetry and command processor; communication system transmitter, receiver and antenna; camera electronics; and power system. Later in the day we will cover structure, propulsion, sensors, solar cells and thermal design issues. (An advantage for our team is that we can all get together this way, since we are indeed the SOUTHERN CALIFORNIA Selene Group!)

Deborah Castleman,
Associate Team Leader

Why Harold Rosen formed the Southern California Selene Group

SCSG — Sun, 10 Feb 2008 18:47:56 -0800

My name is Deborah Castleman. I’m the Associate Team Leader of the Southern California Selene Group.

I want to use this first blog by telling you why we are in this race.

Our team leader, Dr. Harold Rosen, has long felt that space missions of all kinds could be done in a much more streamlined fashioned, using elegant and simple designs that, like a good symphony, are “an optimum blend of the old and the new.” Harold has practiced this engineering philosophy to great effect, and has the awards and commendations to prove it, in addition to well over 75 patents to his name.

Back in the early 1960s, while at Hughes Aircraft Company, Harold conceived and led a small team to build the world’s first geostationary satellite, Syncom. He did it in less than two years, within a small budget, and despite a huge number of obstacles and skepticism. While he was working on Syncom, Hughes was also building the Surveyor series of landers to the moon. Harold felt strongly that, using some of the same techniques he had developed for Syncom, that the Surveyor moon lander could also be greatly simplified and done at far lower cost.

However, at the time he was working very hard on Syncom. Surveyor, the first of which landed on the moon in June of 1966, was not his project.

But that didn’t mean that he didn’t quit thinking about it -- in fact, in the back of his mind he’s been thinking about the best way to land on the moon for the past 40 years!

When he read about the announcement of the Google Lunar X PRIZE, it seemed tailor-made for him: he had no hesitation whatsoever and wanted to sign up right away and form a team. He was able to quickly gather up some of the people that he has worked with successfully over the years on other space projects, as well as some new people, to form our team. Note that these are all busy people, but eager and willing to work with Harold, on a volunteer basis (!!), and to share in his vision. We have already made very good progress on the design of our system.