Upon successful landing of the Perseverance Mars rover this week I felt slightly guilty about my recent dig (January 21) that NASA “can no longer field its own hardware, but ... have a diverse workforce.” As a former engineering professional, I had an inside view of a large (civilian) technology organization. Perhaps that was a somewhat corrupted view to the extent that GTE Network Systems relocated to El Paso in 1978 primarily to achieve the shutdown of the company without having to fight the union workers in Albuquerque, NM and San Carlos, CA (GTE subsequently broke up into Verizon and Sprint, not sure if they still are the local phone company in California). I gradually became aware of this plan as floor-level supervisor of the electronic quality engineering audit program to assure the telecommunications equipment manufactured there met official specifications before being shipped.
Higher management could not convince me to stop my people from failing out-of-specification equipment (leading to an amusing battle where I for a time erected a 10-foot chain-link fence around the quality engineering audit area in order to prevent raiders from removing sample lots to the shipping area) and finally told me point-blank quality no longer mattered since the plan was to cease operations. My own superiors, legitimate engineers, left the company and I was forced onto the second-shift gulag in another position in order to permit the shipping goals to be met without further argument on the basis of quality audits.
After a time, I also left GTE Network Systems and eventually worked for design startups rather than manufacturing facilities, enjoying the highly-motivated highly-talented small-team atmosphere without the layers of parasitic management and HR. As for HR, I recall an amusing interchange with an uncle of mine c. 1977, a pleasantly dull fellow with a corporate appearance who naturally ended up in Human Resources; he had wondered who would hire me as I made the transition from rock and roll musician after 1975. I laughed at him and told him that anyone who actually had to create something or provide a service requiring talent would find me useful.
Transitioning from telecommunications to software engineering, I worked, for example on the AMBI Voice-Data-Terminal design, which, using a proprietary multitasking operating system base (I worked for the designer of that operating system), sent and received email over telephone lines (I was hired to improve their communications software at AMBI because I had background in telecommunications as well as computer programming at the hardware level), and had an electronic calendar, notepad and terminal interface to mainframes in 1985.
At any rate, it is not clear how much of the work resulting in the apparent success of the Perseverance mission thus far is actually to be attributed to NASA directly. After Reagan initiated the destruction of government in the 1980s (and the transformation of the American middle-class into self-loathing serfs bizarrely allied with their greedy masters), NASA found itself with increasingly reduced funding and, quoting from a 2012 report, the country found itself “living on the innovation funded in the past.” NASA had a program executive and scientist in Washington, D.C. for the Mars 2020 mission, but the JPL associated with Caltech very likely did the heavy lifting. The seven instruments and experiments of the rover are each developed by different academic institutions (but one included Los Alamos national laboratory).
The Perseverance was launched from Earth using a ULA (United Launch Alliance, a joint venture between Lockheed Martin and Boeing, founding members of the old military-industrial complex) Atlas 541 rocket with first stage still using a Russian RD-180 engine burning kerosene (RP-1) and LOX (liquid oxygen). They were hoping the BE-4 engine developed by Jeff Bezos’ Blue Origin company could replace the Russian equipment (it must be difficult to talk about sanctioning someone while you are dependent on them for your space launches), but apparently there was some controversy about the government obtaining Amazon free shipping and the replacement has not yet occurred.
The Perseverance was tucked inside a large payload fairing at the top of the long rocket. With the 5 meter diameter payload (first digit “5” in the Atlas 541 designation) sitting on top of a 3.8 meter diameter by 32.5 meter long Common Core Booster, it appears similar to a bacteriophage:
The “4” in Atlas 541 indicates 4 solid rocket boosters were attached to the base of the rocket (a design taken from Warner Brothers Cartoons as I recall, the famous Acme Rocket design used on the Space Shuttle launches). The “1” in Atlas 541 indicates a single engine on the Centaur second stage.
I was surprised to see that US Department of Energy provided the radioisotope thermoelectric generator (MMRTG) providing power on the Martian surface for the Perseverance (don’t see any photovoltaic cells in the pictures so maybe they did not bother with that as a secondary supply, the Sun being somewhat dimmer as far away as Mars, though there is not much air pollution, yet), since that uses plutonium-238, which for a long time after the 1964-1979 detente period, was hard to obtain in the US since we curtailed our production of nuclear weapons materials.
I became aware of the shutdown of production reactors in 2020 when I was researching nuclear reactors in connection with physics articles I wrote concerning neutrino physics. The first experiment to really establish the existence of the neutrino was conducted at the Savannah River site (Aiken, South Caroline) nuclear weapons reactors. This Reines and Cowan experiment culminated in a 1956 congratulatory telegram from Reines to Wolfgang Pauli, the physicist who had invented the idea of the neutrino in 1930 to explain the problem of the continuous beta-decay energy spectrum. In beta minus decay a neutron in a radioactive nucleus transforms to a proton, emitting an electron, aka beta particle, which should have been observed with a single energy spike, but instead was observed with a continuous range of energy as if it was sharing the process energy with an unseen neutral particle, later shown to be the electron anti-neutrino. It had not been thought possible to detect a neutrino, the neutrino largely ignoring most matter, the Sun and the Earth appearing as fine crystal does to light (i.e., crystal is transparent to photons and matter is more or less transparent to neutrinos).
Well, congratulations to NASA, whatever their exact degree of participation. They surely would have taken most of the blame if there had been a problem in what is without a doubt a project with innumerable (even Cantor could not count them) ways to fail.
NASA and space travel being on my mind, I read a 2012 report earlier today discussing nuclear propulsion. The figure there (below) gives the transit time for various nuclear-electric propulsion velocity change capability:
One way of doing nuclear propulsion is by using the heat from a fission reactor to generate electricity, which then is used to accelerate ions and eject them from the spaceship thrusters (engine) at very high velocity. Recall Newton’s Third Law of Motion, whenever one body exerts a force on a second body, the target body feels a force equal in magnitude and opposite in direction, i.e., the rocket is pushed in the direction opposite to the departing ion stream, just as the bottle rocket is pushed away from burning propellant shooting out the back. A nuclear reactor is heavy and the thrust is relatively low compared with chemical engines, so it must be operated continuously to achieve the desired delta-V (change in velocity). It therefore takes a long time to get up to speed and a long time to decelerate at the destination. So you see the flight transit times estimated for various length missions (that does not take into account ion propulsion advances in the last 8 years though, I have a NASA facility relatively near my location out in the desert and they have their own private high-power electric lines, so make of that what you will).
What caught my interest in the figure though was the label “Interstellar Precursor.” A tear involuntarily came to my eyes as I read this. Interstellar, that means “between the stars.” That implies a destiny beyond a an overpopulated box of bipedal mammals (a specific mammal came to mind but I censor myself for once) with increasingly low intelligence and nasty temperament. Why such a personal connection for me with that idea of interstellar travel?
I knew a man in 1962, in or out of the body, I cannot say (some may recognize my style here as that of Paul 12:3 in his Second Epistle to the Corinthians). But he went out to investigate a strange object late one night in the southwest desert and perhaps experienced things which it is not allowed to relate. He began to dream of things to be, sense the thoughts of others, and to live more or less a life parallel to the one here on this workaday planet. He suffered much though--as usual such men must be reminded of their mortality and human frailty, but gold is tried in the fire, and acceptable men in the furnace of adversity (Ecclesiasticus).
My recent work has shifted to pure mathematics after devoting the last four years mostly to quantum mechanics and then neutrino physics (though that necessarily included a significant amount of applied mathematics). I just published a tutorial on automated theorem proving with the Isabelle Proof Assistant Isabelle Proof Assistant Tutorial. As a friend observed, “well, at least you stay busy.”
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