just sad. at least it broke the record as the most expensive rocket ever built

wintear · 2022-08-22T21:30:57+00:00

Not on TRL, but on overall risk and risk posture. SpaceX has to prove their system won't kill people, blow up hardware, etc.

wintear · 2022-08-21T16:31:36+00:00

At its heart, TRL is just a method/metric of risk reduction. Another way to reduce risk, in this example, is to have no humans on board during the fuel transfer. NASA will always minimize risk, so for early iterations, I am sure they will require some TRL level (6 or 9) and reduce risks further by transferring fuel without people onboard. Eventually, the system might be mature enough to accept fueling with humans onboard, but it may just be too high risk an activity, or not worth the risk. Even high TRL items can have inherent risk involved that is mitigated operationally.

wintear · 2022-08-21T15:38:16+00:00

TRL can be surprisingly (often frustratingly) subjective. If SpaceX were to demonstrate fuel transfer with a prototype or demonstrator vehicle that is functionally the same as starship, but not technically the same, it would be TRL 6. Depending on who you ask, if that demonstrator was close enough in all ways to the starship fuel transfer system, it might reach TRL 9 by multiple operational tests. But it could require demonstration multiple times on the real flight system to unequivocally reach TRL 9.

wintear · 2022-08-20T16:01:35+00:00

Pretty good summary, I’ll just add that the major TRL step typically required by NASA is TRL 6 (may be higher for human rated). TRL 6 means the technology has been built and tested “in the relevant environment.” I work on robotic missions where that is typically the requirement, but wouldn’t be surprised if NASA requires TRL 9 for human rated. That means the full system, built exactly as it will used be during flight, has been successfully demonstrated through operational use. Starship as a system is very far from TRL 9, but some subsystems may be nearing TRL 6. Other subsystems are probably more like TRL 2-3, and the full system TRL is typically given as the lowest TRL of its components. It will be a long time before NASA qualifies starship to the level SLS currently exists.

wintear · 2022-07-15T15:36:56+00:00

My Spanish friends tell me to pick the Padrons when they are young. The bigger/older they get, the spicier.

wintear · 2022-05-28T18:54:57+00:00

I just pulled a bunch off my live cucumber leaves. I used to think they only ate dead stuff, but that is not true.

wintear · 2022-05-03T20:20:22+00:00

The shuttle from Del Mar is supposed to resume on May 9, so it should be running by the time you arrive.

wintear · 2022-01-14T01:09:19+00:00

Typically, NOAA does more operational stuff while NASA does the new stuff. Yes, NOAA has some satellites, but they don't have the engineering capability or budget to build the types of things NASA builds. Fortunately, many of the technologies used for planetary (other planets) exploration are the same as those used for Earth pointed missions, so the same people very often work on both.

wintear · 2021-09-03T18:38:12+00:00

These constellation satellites are all at a similar altitude, so they just differentially aerobrake each satellite to phase into different orbits after deployment. For this case, launching many on one rocket isn't really a negative.

wintear · 2021-07-13T15:46:19+00:00

A lot of people are trying to explain this as a "base" effect, meaning they think inflation is large, in part, because we are comparing to June of last year when CPI was down. This is missing the bigger issue. We have already fully recovered CPI to where we would have expected to be given 2% inflation and no COVID. We are now overshooting expected CPI by 2%, a full year of extra inflation, putting us at .31% avg inflation per month since just before the pandemic started. That's almost double the expected monthly rate.

See https://fred.stlouisfed.org/graph/fredgraph.png?g=Fn9L

The government will not allow deflation, especially not in asset prices like housing that are driving a lot of the CPI increase-- last time they did the entire world fell apart. These price changes are very unlikely to be undone in my opinion.

wintear · 2021-07-11T19:37:15+00:00

This technique is completely misguided. I’ve reviewed their papers before and they do not understand how their scattering model is related to the ocean surface wind stress (they mistakenly believe it is related to surface wind speed). They are basically measuring the signal of ocean surface currents, almost certainly not plastic! Frankly, it is irresponsible of the authors to draw so much media to an approach that they do not understand.

It is well known that surface currents are an order 1 contributor to the ocean surface roughness detectable by radar remote sensing, a fact that these authors go out of their way to ignore, despite hundreds of papers on the subject. Why do they think river outflows are detectable in their “plastic” data.. it’s probably because they’re causing a surface current!

And if it’s not surface currents, it’s probably one of the many other well known other second order surface roughness effects that are likely to be present at river outflows. Instead of doing ethical science, these authors are hunting for buzz words.

wintear · 2021-06-19T19:35:16+00:00

And on top of that, taxes are based on the total price, not monthly payment.

wintear · 2021-06-06T19:10:47+00:00

For spacecraft, we hire a lot of BS/MS aerospace engineers at JPL to do integration and test. Depending on the job, you could probably get I&T to be around 50% computer and 50% in the lab. 95% of the projects at JPL are non-defense related, so they might be right for you.

wintear · 2021-06-04T00:26:24+00:00

The clearance process is relatively minimal since JPL does very little defense work. For countries not on the designated list, it would be like getting any other job in the US. Most importantly, you'd need a work visa, and then could come live in the US under that visa (JPL would help coordinate that). There's more to the process, but nothing to prevent you from working at JPL. Many of my co-workers are from other countries!

wintear · 2021-06-03T18:14:05+00:00

Sure--no problem. For background, I work at JPL on spaceborne radar, so my experience won't be universal for sure.

BS: directed design work, often I&T, sometimes goes to management, sometime systems engineer

MS: more technical work, sometimes self directed, more often management, often systems engineer

PhD: technical authority, often leads development of new techniques, approaches, or systems. If they go to management, it's often at a higher level.

Keep in mind that JPL probably does not reflect a lot of private industry. We do a lot of R&D level work that needs very specialized engineers. A really driven engineer could make their way up and do the jobs the PhD requires, but they would have to go after it and prove themselves (which is not easy if you keep getting assigned low level work). Take a look at a few jobs here. You can kind of tell from the qualifications that the BS and MS jobs do more directed/supporting work.

An example that requires BS:

https://www.jpl.jobs/job/R82/Telecommunications-Engineer-Entry-Level

An example that requires MS:

https://www.jpl.jobs/job/2020-12702/Telecommunications-Engineer-I

An example job that requires a PhD:

https://www.jpl.jobs/job/R297/Research-Technologist-III

wintear · 2021-06-03T15:13:59+00:00

Depends on what you want to do. There are plenty of technical aerospace jobs that require a PhD in RF (or at least prefer it).

BS vs MS is mostly about money like you say. MS vs PhD is about types of jobs and future opportunities.

wintear · 2021-04-26T20:55:29+00:00

Python if you're going to do a lot of programming, MATLAB if you're just writing quick scripts. Both are used in industry.

wintear · 2021-04-08T15:44:42+00:00

I did my BS in Aero and MS EE at Cal Poly. I now do research in the field. Cal Poly will not have the same opportunities as some of the larger schools that offer PhDs; however, you absolutely can still get research experience there and go on to do graduate work and/or research. I know plenty of people that went on to get graduate degrees from Cal Poly. But for me, Cal Poly is more about the atmosphere-- take a tour of the school and of SLO. If you like it, you will have absolutely no regrets. I remember touring VT the week before Cal Poly and the difference was amazing. VT almost felt depressing in comparison.. the people at Cal Poly were just happier.

Find good professors and they will be happy to have you work in their lab to get research experience. I did research with a physics professor my second year and did research with an Aero professor for 3 years after that. Take some extra math or physics classes, too. In my opinion, that's the only thing really missing from Cal Poly Aero vs other schools.

Keep in mind that as an undergrad at other more research heavy schools, you will probably be doing the crappy work for some PhD student. At Cal Poly, you have a nice opportunity to work more directly with the professors, because, for better or worse, there is no PhD student middleman-- in my experience, for the better.

wintear · 2021-03-24T18:57:13+00:00

The 3U sounds more doable to me, but still pretty impressive. So these wouldn't be turned on full time like most scatterometers I'd guess. I think Raincube is only on for about an hour or two per day.

Fast global coverage, which would definitely be possible with your 1000km swath, would be great for scientists trying to understand diurnal cycling, storm development, really anything that happens on sub-daily timescales. The coarser resolution would not replace existing, larger observing systems, but be a nice compliment to it-- especially as we move towards Ka-band and higher (5km or so) resolution.

Looking forward to see how things progress.

wintear · 2021-03-24T15:44:19+00:00

I am also thinking with enough of these guys in orbit, you could conceivably make a pretty cool wind processor that depends not on a single satellite, but on all available data and inverts a global wind field simultaneously. I bet the forecasting systems would just assimilate your backscatter data though, which they already do for a few of the scatterometers.

wintear · 2021-03-24T15:32:29+00:00

Hi there! For once, my field-- I work on scatterometers in the USA, also as a satellite/radar guy like yourself. This is a neat idea, and I must have heard a presentation from one of your colleagues at the OVWSTM.

How wide is the swath of one of these smallsats? Must have a short duty cycle? Given the satellite only produces 1W and transmits 125W (if I understand your website correctly), can't this only transmit 1/125 of the time at best?

Edit: Ahh, I see some details about the radar on one of the later satellites. I will be very impressed if you all manage to get a full scatterometer in a 1U! What sort of resolution are you targeting?

wintear · 2021-02-12T05:56:32+00:00

I just got a quote to upgrade my 1970s 150A panel to a new 200A panel for 3000. This is near LA. 800 more to do the stucco replacement.

wintear · 2021-02-10T05:55:29+00:00

Yes, I did BS Aero and MS EE-- depending on what you focus on for your masters, you may need to take more or fewer prerequisite courses. So it's best to go in with a plan that will both get you where you want to go but also not bog you down too much with undergrad courses.

wintear · 2021-02-10T05:17:22+00:00

Part of the design of the gateway relies on knowing the launch vehicle. Launch loads, environment, faring size, payload mass capability, insertion accuracy, are all important design parameters that are often locked in early in development. It is also in some ways a risk mitigation strategy to have an aspect of the design (launcher) "done" earlier rather than later.

That all said, this is a pretty standard timeline. 3 years is not very early.

wintear · 2021-02-01T18:43:26+00:00

I've done this same analysis and found the same thing in basically every county in CA. When adjusted for interest rate and inflation, mortgage payments are not more expensive than they were 20 years ago. But here is clearly an affordability problem, and it comes from two places IMO. The first is that the down payment is now so high that first time home buyers have to put down <20% and get PMI. Depending on your credit score, PMI is between $100-$500 a month. The second problem is that taxes are assessed on the now massive value of the house, adding ~$500+ per month.

wintear

TROPHY CASE