Andrew Peregrin Goff

There are probably less than 5 people in the world who a) care about my family life, b) don’t follow me on twitter, c) don’t follow Tiffany on Facebook, d) didn’t get an email about this already, but e) do read this blog. So for those of you who fit in that category, I’d like to announce the birth of our son Andrew Peregrin Goff. Andrew is our fifth son after Jarom (deceased), Jonathan (9yrs old), James (7), and Peter (5).

Andrew was born this Wednesday evening at 5:20pm in Boulder. He was two weeks early (but still technically full-term), 6lb 11oz (3.03kg), and 19in (48cm) long. He’s doing great, and both he and his mother are home as of this afternoon.

If you’re wondering about the name, Andrew is my middle name. We also have several friends with Andrew as a first or middle name. It also fits with Peter, James, and Jonny (sort of) as a sort of semi-intentional Apostolic naming theme. We debated a lot of middle names–Andrew is somewhat tough to find good middle names to go with. Our two finalists were Sheridan after Tiff’s dad, and Peregrin (yes after Pippin from Lord of the Rings). We ended up going with Peregrin in the end. The good news is that with a middle name that can be shortened to Pippin, he’s set whether he’s a LOTR-fan nerd like his dad, or whether he gets into basketball…

After having picked the names, we found out that Andrew means “manly or brave”, and Peregrin (which amusingly enough was the word of the day on today) has connotations of wanderer, traveler, etc.

His current nicknames are spud, french fry, burrito, and self-eating-burrito.

Here are some pictures of baby Andrew:


Posted in Family | 10 Comments

Dragon Tug

With the Dragon capsules fully capable of ISS interaction now, how hard would it be to use the dragons for ISS tugs as is?

One of the quite useful pieces of on orbit hardware is a space tug that off loads the critical maneuvering capabilities from the launch vehicles. A launch vehicle that does not need those capabilities will be simpler and cheaper, not to mention safer, than one that does require all the bells and whistles. I am wondering if the capability to accept cargoes from multiple  suppliers for the ISS has stealthed its’ way into operational use without any of us noticing.

It would be interesting to know if Atlas and Delta, or even Sea Launch and foreign suppliers, could deliver payloads to just outside the exclusion zone for a Dragon to tug to ISS. Financially it wouldn’t seem to make sense. Politically though it might get several more players pulling in a positive direction. If it suddenly became blindingly obvious that several suppliers could safely and reliably surge major tonnage to an orbital berth, the argument for the Big Rocket would take another hit.


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So I’m sitting in a friends yard watching the Blue Angels give it their best at the Sun-N-fun fly in thinking about how to modify their propulsion while all the people around me are oohing and aahing. Same with the F22 demonstration and various prop planes. I guess some of aren’t meant to watch these super skilled pilots do phenomenal things without focusing on the hardware.



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Certification and Rules-based Technology Regulations: Part of Why We Can’t Have Nice Things

Brian Wang over on Next Big Future brought up a point I’ve been thinking about for a while. In an article about why Canada is likely to beat the US to having molten salt nuclear reactors (in spite of the US pioneering the field back in the 60s), Brian hit on the key reason:

There is an important difference between the Canadian and the US regulatory authorities. The US is rule-based and Canada nuclear regulations are output-based. In the USA, anyone wanting to develop a new type of reactor will have to prove its safety before it exists. All of the US rules are based on light water reactors. In Canada, you will have to prove the safety of your concept while it is operating. Terrestrial IMSR seems to moving ahead very quickly. Canada’s nuclear regulators could allow a molten salt reactor to be built and operating in 6 years.

Simply put, US nuclear safety regulation is based on the idea that regulators from back in the 60s knew the best way to make a safe nuclear reactor, and that compliance to their rules was the best way to guarantee a new reactor was going to be safe. The problem is this kind of assumes that technology stands still and that new approaches with fundamental safety benefits aren’t likely. The sad reality is that this is why we have disasters like Fukishima–old reactors get grandfathered into the regulations, new reactors that could be dramatically safer or even passively safe get delayed so bad by regulations that they in many cases never get completed. So we’re stuck with older, less safe technology, all in the name of safety regulations.

You see similar dynamics in aircraft certification, and the current arguments about regulation of suborbital RLVs. George Nield, who I normally have a ton of respect for, recently argued against extending the “learning period” under the Commercial Space Launch Amendments Ac said that:

“The US has over 50 years of experience in human spaceflight,” he argued, providing a large set of lessons learned for commercial spaceflight providers. “For us to just put that aside and start over without taking advantage of what we’ve learned, I think is irresponsible.”

It’s true we have some experience, and that info should be provided to suborbital developers to build off of, but it makes the same fundamentally flawed assumption that’s stifling nuclear technology in the US–and which is making nuclear power less safe in the name of safety. We have a bit of experience now with manned capsules, and shuttle-type winged reentry vehicles. But assuming that we’ve now reached the pinnacle of reusable launch vehicle design is likely going to look laughably foolish in the future, possibly even the near future.

In some ways this line of argument might look like one a Department of Ground Transportation official could have made in 1907 about safety regulations for ground vehicles such as horse buggies and automobiles. After all, by that point, we had centuries of experience with design and operation of horse-driven ground transportation. We shouldn’t just throw that out and ignore it. We know enough to make reasonable safety regulations. I mean, how much are these automobiles going to change from horse buggies–heck the current ones even look really similar.

It would be sad if a few years from now safer launch vehicle and reentry vehicle technology had to go to places like Canada because the US was so sure it knew enough to make rules-based regulations to “certify” the safety of the industry.

Posted in Commercial Crew, Space Policy, Space Safety | 6 Comments

Introducing Taong Boondocks

FYI, I just created another blog, called Taong Boondocks, which will focus on all the non-space related topics I care about. Fair warning, I’ll be blogging about my family, hobbies, religious, political, and economic musings, etc. So if your only point of agreement with me is on space you might want to stick to Selenian Boondocks for now.

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Insert Lame Excuse Here

Hey guys, I apologize for not getting the follow-on posts for the “Slings and Arrows” and “Venus ISRU” series put up before I got overwhelmed with SBIR silly season (and several other work projects). I’m really going to try to get to them as soon as I come up for air, hopefully at the end of the month. I hope you’ve enjoyed my burst of blog productivity over the past two months. Hopefully once these proposals are knocked out, I can get back to things.

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The Slings and Arrows of Outrageous Lunar Transportation Schemes: Part 1–Gear Ratios

[Note: I haven't quite finished with my Venus ISRU series, but some of the articles I've read over the past few days drew me back to this series on propellantless lunar launch approaches that I started writing four years ago but never finished. While Venus ISRU is interesting, I still think it's pretty likely that the first operational ISRU (ie beyond demo or pilot-plant scale) will be on the Moon.]

One of many important issues that doesn’t get enough airtime when discussing lunar ISRU is how to efficiently get the propellants and other materials off the lunar surface. There seems to be a line of thinking that could be called “all we need is ISRU” that says that lunar ISRU is the most critical technology and everything else is just a distraction.

While it is possible to take propellant produced on the lunar surface up to LLO or to one of the Earth-Moon Lagrange points using similar rockets to what you landed with, and then deliver this to LEO using entirely propulsive tugs with no new technology, this isn’t very efficient. You end up spending a significant fraction of the lunar derived propellant lifting both the delivery propellant and the landing return propellant, as well as the propellant to ship the cis-lunar tanker back to LEO and bring it back for refueling near the Moon.

To give you an idea of how inefficient, I’m attaching a spreadsheet with some back-of-the-envelope level calculations to illustrate this point. In the spreadsheet I model a Lunar Surface to LLO or EML-2 and Back tanker, and then an LLO or EML-2 to LEO and Back tanker. In both cases, I assumed they were about Centaur size (~23tonnes), and used RL-10 based propulsion. For the reusable lunar surface tanker, I gave two propellant mass fractions–90% (aggressive once you factor in landing hardware) and 85% (more conservative). For the cislunar tanker, I assumed a 90% propellant mass fraction, and also analyzed cases where an aerobrake was provided that weighed 5% of the GTOW and 10% of the GTOW.

In the most extreme case of “all you need is ISRU” thinking, where you use entirely existing chemical propulsion systems for getting propellants from the lunar surface to LEO, only 9-11% of the propellant produced on the Moon actually makes it to LEO.  Alternately, this means you have a “gear ratio” (ratio of propellant extracted on the Moon to propellant delivered to LEO) of 9-11. Not only is this very wasteful, but it means that you would need to size your ISRU capacity significantly higher than if you had a more efficient system.

Of the approximately 12km/s of round-trip Delta-V from the lunar surface to LEO and back, there are several options you can use to improve your gearing ratio, each of which attack a different leg of the journey:

  1. Stage and refuel in LLO or EML-1/2 (which was already assumed for this analysis).
  2. Aerocapture/braking to go from your Trans-Earth Injection trajectory into LEO
  3. Propellantless methods for launching from the lunar surface to LLO, EML-1 or 2, or even directly to LEO.
  4. Propellantless methods for landing on the Moon from LLO or EML-1 or 2
  5. Propellantless or high-Isp methods for traveling from LEO to LLO or EML-1 or 2.

This series is focused on options #3 and #4, though #2 is also low-hanging fruit (and provides about a 2-3x gear ratio improvement over the baseline “all we nee is ISRU approach).

Next up: Five Propellantless Lunar Transportation Approaches

Posted in ISRU, Lunar Commerce, Lunar Exploration and Development, Space Settlement, Space Transportation | 63 Comments

New Link and Blog Layout Update

Earlier today, Trent Waddington tweeted about a blog post about lunar robotics on Hop David’s blog. I’ve interacted with him on over the years, so decided to check it out. I don’t agree with everything, but it’s well worth the read. Especially for some of his cartoons/graphics. The guy’s not just smart, but he’s got some real artistic talent to go with his engineering talent. The only thing that could make his site better were if it wasn’t a blogspot site… But regardless of that, I’d strongly recommend spending some time over on his blog.

In other news, I decided that I hated the twitter feed widget. If I knew how to shut off the avatars, it might make sense. But with the twitter avatars, the amount of text space is so small each tweet ends up wrapping to half a dozen lines. Useless. Oh well.

Also, I decided to change the blog theme. Mistylook was getting old. One of these days I’ll need to do a custom banner header. But for now, this should do.

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Ender’s Game Movie [Warning: Contains Pedantic Spoilers]

So, I finally went to go see the Ender’s Game movie tonight, before it left the theaters. In hind-sight, reading the book cover-to-cover within 48hrs before seeing the movie was probably a bad call. If you haven’t read the book, I’d recommend the movie. If you have read the book, I’d probably still recommend the movie, in spite of my gripes (unless you’re one of those people who hate very movie ever made from a book, cause you’ll probably have an aneurism). After thinking through the movie on the way back, I talked myself out of most of my gripes (you shouldn’t have to do that for a movie), realizing that it was the limitations of trying to cram a six year story into a less than 2hr movie. But I did still have one pet peeve, and I’ll put my rant below the fold, since it contains spoilers for those who haven’t yet seen the movie.

Continue reading

Posted in Movie Review | Tagged | 17 Comments

Penny for NASA (Centennial Challenges)

I remember the first time I was exposed to the fact that NASA gets less than 1% of the federal budget, and the suggestion that we could do so much more awesome stuff if NASA just got 1% of the budget like it used to. I was 16 at the time, and I was in my freshman year at BYU. I was so fired-up by this idea that I used the idea as the topic for a persuasive writing essay for my Creative Writing class I was taking that semester. The sad thing is that in the 17 years since then, the Penny for NASA arguments have gotten no more convincing than my paper (which probably only earned me a C+).

My biggest beef with the Penny for NASA concept is that I think NASA is doing a lackluster job of effectively spending its current ~$17B/yr. There are not so far-off technologies that could slice the cost of deep-space manned missions by 2-5x, but funding for those technologies are getting starved, while most of the money gets sucked-up by politically untouchable mega-projects. If NASA’s budget were doubled, Congress would probably run out of excuses, and send some money towards technology development and demonstration, but that funding would also likely be the first to get cut if NASA’s budget were ever reduced in the future. And seriously, who here thinks that if NASA’s budget were doubled it wouldn’t be come a lightning rod for cost cutting in the future? No, I’d rather see NASA more effectively spend the money it has, and is somewhat likely to keep, than hoping for solving all problems by shoveling more money at the agency.

What I think would be a more useful spending goal would be to advocate for spending at least 1% of NASA’s budget on prizes, such as the ones that have been run by the Centennial Challenges.

You’ve heard the benefits of prizes before, but to reiterate:

  1. Prizes only reward success, not effort. Far too much of NASA’s money is spent in a way that does not guarantee the taxpayer gets anything in exchange for huge investments.
  2. Far less of the money and effort associated with winning a prize is spent satisfying bureaucratic requirements/oversight than with even COTS-like contracts. There are some regulations such as FAA regs that have to be followed, but the overall percentage of prize efforts spent on hardware/operations versus paperwork is much more optimal.
  3. Well-structured prizes often help encourage multiple players in an industry even after the prize is completed.
  4. Prizes encourage creative, out-of-the-box solutions that might have been rejected by a selection committee for normal funding.
  5. Prizes can often encourage non-traditional players to compete.
  6. Prizes are often more exciting and engaging for the public than similar traditionally funded technical efforts.
  7. Prizes can often get ego-capital investments into risky new technologies that might not have happened based purely on financial merits.

That said, prizes don’t solve all problems, I’ll be the first to admit that. Prizes don’t guarantee that people will be able to raise the money to pursue them for instance. Especially when the prize value is too low compared to the likely cost to complete it, and when there’s no clear near-term commercial follow-on opportunity. Prizes tend to attract for more teams than it attracts credible teams. Of the something like 20 X-Prize teams, I think that Armadillo was the only other semi-credible team other than Scaled, and they were way behind Burt Rutan’s team. Of the something like 15 teams competing in the NGLLC, we did better, with about 5 pretty serious teams by the end (in addition to the two winners, Unreasonable Rocket, TrueZer0, and Paragon Labs all at least built and had stable tether tests with vehicles that could’ve won the prize with another year of practice and refinement). No comment on GLXP.

But while there are definite tradeoffs with prizes, it’s also pretty clear that they’re getting woefully underfunded compared to the rest of NASA’s spending priorities. At its best year, I think Centennial Challenges came close to getting 0.1% of NASA’s total funding, and most years it has received significantly less than 0.05%. While I agree there is room for debate on how effective prizes are compared to traditional contracts, I’m pretty sure nobody seriously thinks that they are 1000-2000x less effective.

So, I propose the idea of setting aside 1% of NASA’s budget for prizes.

Really, in the grand scheme of things, a 1% tax on other NASA programs wouldn’t be felt by most of them, only the programs that have been hit the most with spending cuts (like Planetary Science) would likely notice them at all. And having a pot of $170M per year for prizes would enable a wide range of prizes that NASA has so far been unable to even offer, including prizes related to technology development/demonstration capabilities they’d like to fund, including: reusable launch systems, nanosat launch, microreturn vehicles, interplanetary cubesat missions, Lunar/Asteroidal/Mars/Venus sample return and/or ISRU demonstration, cryogenic propellant storage, handling, and transfer technologies, deep-space human spaceflight issues (like radiation protection, artificial gravity, etc). When you’re only getting $4M/yr or less, you’re stuck with either funding prizes for really tiny efforts, or badly underfunding prizes for slightly bigger (but still quite small) efforts.

Here are a few suggestions I’d have for making this better funded Centennial Challenges program more successful:

  1. Place a cap on the fraction of the budget that can be spent on administrative personnel. I’d suggest say 5%. 5% of $170M still works out to over 40 full-time support staff.
  2. Setup Prize Manager positions in the Centennial Challenges program in a method similar to how DARPA handles Program Managers, where they are only brought on for a set period of time (typically about 3 years). Encourage bringing people on from academia, industry, and military space, not just NASA employees. This encourages more diversity of thought and cross-pollination, while also decreasing the ability for people to empire-build.
  3. Make prize winnings tax-exempt (I’m not sure if they already are, but they ought to be–that’s one way of making them more lucrative that doesn’t cost much extra money).
  4. Set aside some money for paying the partnering groups that run the prizes. I’d still limit this to no more than say 5-10% of the total budget. But providing some financing to the prize groups would mean that the prize groups wouldn’t be spending so much of their time trying to raise money for themselves instead of running the prizes effectively.
  5. It might also be worth setting aside one last 5% of the budget for media/promotion of the prizes and teams. If the prize organizations aren’t having to raise money to cover their own cost, and media groups aren’t having to pitch Hollywood on funding media efforts, there’s a lot higher probability of being able to gain visibility for both the prizes and the teams involved.
  6. Require that the other 75% of the budget can only be spent on prize payouts, and keep the current Centennial Challenges ability to retain money unclaimed from year-to-year.

While there are probably tweaks or adjustments to this plan that could make it work better, and while 1% is a bit ambitious, I still think this is much better than just trying to up NASA’s topline budget by a factor of 2x, and a lot more likely to result in lasting benefits than doubling NASA’s budget.


Posted in Commercial Space, NASA, Prizes, Space Policy | 16 Comments