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A helicopter carrying Ebrahim Raisi the President of Iran has gone missing in a remote region of NW Iran close to the border with Azerbaijan. Foreign minister Hossein Amirabdollahian is also said to have been onboard the same craft which was part of a convoy of three helicopters that were returning from a visit to mark the inauguration of a new dam in neighbouring Azerbaijan. https://www.aljazeera.com/news/liveblog/2024/5/19/iran-helicopter-accident-live-president-fm-on-missing-aircraft Various reports from Iranian news agencies say that the helicopter made a “hard landing” somwhere near the Iranian border town of Jolfa. Iranian rescue teams are struggling to reach the location because of the rugged terrain and heavy fog, with Iranian TV showing visibility down to 5m in places. Two other helicopters in the same convoy made a safe return, and some Iranian sources indicate that an emergency phone call was received from some of the people onboard the missing helicopter. Other sources say that Iranian TV is currently screening recitations of verses from the Quran, and that the VP has already formed an emergency government. The helicopters used to transport the Iranian president are ageing Russian made Mil Mi-17 military transports which date back to 1975. They have been involved in a number of incidents and crashes in recent years.

He’s a know-it-all, and some would extend that to insufferable know-it-all. Some fraction of the population gets annoyed at nit-picking, and some fraction enjoys diving into minutiae. There will always be conflicts of this sort with public figures. (I mean, some people didn’t like Mister Rogers)

A preliminary NTSB report on the collision of the MV Dali with the Francis Scott Key Bridge has been published. A detailed read-through of the provisional findings can be found here: https://www.youtube.com/watch?v=etCUog15pWA Fuel contamination was apparently not the cause of this accident. There were 3 different types of fuel in use onboard the Dali, and all the samples tested clear. The problem seems to have been entirely electrical in nature. The Dali suffered two major power failures in quick succession; the first took out the HR1 and LR1 overcurrent breakers either side of a large transformer which linked the 6600V diesel generator bus to the main low voltage 440V power bus. This failure disabled the lights, comms, navigation systems, and most critical of all, it took out the power to the oil pumps and cooling water pumps servicing the main engine. The loss of these pumps triggered an automatic shutdown of the main engine. The second electrical failure occurred as the crew attempted to restore power to the 440V bus. This time two current overload breakers DGR4 and DGR3 failed, which disconnected the two main diesel generators (#4 and #3) that were online and supplying the high voltage 6600V bus. (Two of the four main diesel generators have to be online to restart the main engine). An emergency generator re-powered the three steering pumps which enabled the pilots to exercise some degree of rudder control, but unfortunately with the main engine and propellor stopped, the steering effect of the rudder is very much reduced. With the Dali only 0.6 miles - or 3 ship lengths - from the Key Bridge when the first electrical blackout happened at 0125, there simply wasn’t enough sea room to avoid a collision. One relevant detail mentioned in the report was this: Which explains why they couldn’t simply ring up "Full Speed Astern" on the engine telegraph.

Depends on the species. Franklin's 50/500 rule is often cited for humans (I just wrote on this on another thread but can't find atm) and that top number is seen as what is needed for longterm viability and sufficient genetic diversity. Lower numbers and a species can wither. Too much inbreeding, losses of useful genetic variants to genetic drift, etc. Most mutations are deleterious, about 75-80% of single nucleotide variants, so the lucky dice roll of a positive mutation (roughly 1-2%) that adds useful diversity is going to be rare in too small of a population. I've seen debate on the number, but there seems to be some agreement that 500-600 is enough for humans. I know NASA has funded some studies on this, with a longterm view to understanding what are viable populations for establishing colonies on other worlds.

Cryptic as always, even on such a somber day. My deepest condolences, Dim.

Sorry to hear of your loss Dim. May he RIP.

The velocity (both speed and direction) of an object like an asteroid is very frame dependent. So you seem to envision the frame of the sun say, where the asteroid is on a path not towards Earth, but one that will cross Earth's orbit exactly when Earth gets there. You hit it straight on in a direction opposite its motion in that frame. It slows, and the mostly unaltered paths still cross, but the objects are at that point in a different times. Now do that from Earth frame (the frame from which the rocket was launched). In that frame, Earth is stationary and the the asteroid is heading straight for us. If we hit it straight on in that frame, it will slow, but still get here a little bit later. Point is, a straight bullet shot fired from Earth isn't going to divert it. In that frame, to get it to miss, you need to apply lateral momentum to it. This involves sending the rocket on a curved path, wasting fuel compared to the straight path. And only the fuel expended for the lateral motion will effect the asteroid in a deflecting way. So you need a lot of fuel. One batch to get there (all unusable for deflection) and a whole separate batch to apply laterally to the thing. All this kind of presumes flat inertial motion of both Earth and asteroid, which is accurate if the thing is pretty close, but the idea is to get it when it isn't so close since it takes less effort to divert something far away. A smaller deflection is needed to effect a miss. So maybe our computers predict this collision on some prior orbit and we can manage to hit the thing slightly on some prior pass. Idea is to not hit it when it crosses Earth orbit since no defection there will prevent it from returning to Earth orbit repeatedly.

I found the Dali's electrical problems kind of surreal. (too soon?)

I thought it was clear. What are you unable to understand?

You see it is easy to confuse all of these terms, a real digitally-automated user-interface that can do any of the things in my topic title fully utilizes almost every quantum phenomenon in gestalt except maybe electrodeionization (preferring to use photoconductivity in one of the components). It can even make use of a combination of photovoltaics in unison with electroluminescence and excitons that, when combined with my own type of photoionized-electroluminescent laser receiver can multiply the energy reabsorbed back into a laser-based plasma-fusion reactor. For the synthesis of the materials exhibiting these quantum properties from natural places on earth I would suggest starting with crystals and metallics (with the understanding these form from various volcanic and hydrothermal activity that heats, mixes, and ultimately transmutes rock-based materials from all different places carried to one hydrothermal vent by oceanic current or some other volcanized area via plate tectonics) along with chemical reactions in the lab. Might I suggest creating deep subterranean tunnels to release pressurized volcanic flows of ionized gas and magma directly into a facility that needs both the heat, ionized gas and the material in magma flows to do the work? The Mariana's trench is the deepest place on earth and therefore the best place to start on such tunnels. Constructing the hollow earth would be the best way to initiate the next era of manufacturing mass amounts of tech and industry.