This week we will examine a new type of jet engine that is efficient at all speeds of flying. Initially the engine will be used to deliver rockets to space and eventually for commercial passenger airliners. The expectation is that aircraft using the engine and associated technology will travel three times faster for the same cost. We investigate the significant progress being made towards developing a universal snake anti venom. We look at a breakthrough in superconducting magnets that brings fusion energy much closer to reality and finally we discover some red supermassive black holes from the early universe.
Adaptive Electric Jet Engine
Astro Mechanica, a San Francisco based startup is developing the first electric adaptive jet engine. An electric engine is used to alter the characteristics of a turbine engine at different speeds. Why do this? It is vastly more efficient over all speeds.
We currently use different engines for different air speeds and needs. This is due to the different efficiencies of each engine at different speeds. This new electric engine can adapt the turbine engine to the required airspeed. The adaptive airframe and engine will allow you to fly from the ground to Mach 2.7 at maximum efficiency. The different components adapt to the need at the time.
One thing to note is that a traditional engine and fuel is still used to power the plane. The electric engine is used to control the airspeed into the plane engine. Different types of engine use different airspeeds through the engine to create propulsion . Each type of engine is more efficient at different speeds. The ability to adapt the airspeed through the engine as required by the speed of the plane is the difference maker.
We currently use rockets to get to space. They need to carry a lot of fuel to achieve this feat. Anywhere from 88% to 92% of the weight of a rocket that takes off is propellant, the rest is rocket and payload. It takes a lot to move a small payload to space. Rockets are also structurally quite weak. SpaceX has improved their rockets so that they can be used between 10 and 20 times.
This compares to a commercial airplane which is designed for 30,000 cycles. These aircraft carry far less fuel however are much slower than rockets. In a jet engine, air is mixed with fuel and combusted. Rockets have to carry their own liquid air for the combustion with the kerosene fuel. Jet engines can’t go into space as there is no air in space.
Engine efficiency is vitally important to economic success in flight. For example the Concorde used 40 to 50% of its fuel load on the ground taxing and then getting to initial cruising altitude. The plane was very efficient at altitude where the supersonic engines were at maximum efficiency. It was incredibly inefficient on the ground and climbing at slower speeds. Rockets face the same problem. They are extremely efficient at high speed but burn most of their fuel in the initial take off and acceleration.
One way to think about getting into space is that space is an altitude whereas orbit is a velocity. You can only go into space if you are going fast enough to escape earth’s gravitational pull, that is about Mach 25 (25 times the speed of sound). Using the electric adaptive engine a plane will fly from ground to around Mach 2.7 before deploying a second stage with a ramjet engine (with the space vehicle and payload) to speed up to Mach 6. Then there is a second stage separation leaving a rocket which speeds up to Mach 25. That will take the vehicle to space.
The electric adaptive engine controls the airspeed through the engine. As a result it is far more efficient and cost effective in getting to Mach 2.7 than traditional rocket boosters. The same engine works efficiently at different velocities. The electric motor is inserted where a gearbox used to be. As electric motors are 98% efficient, the energy from the electric motor is able to be programmed. The speed of air through the engine (faster or slower as required) can be controlled as for maximum efficiency.
This graph of propulsive efficiency shows how the 3 different types of engines operate at different speeds.
One engine to operate at maximum efficiency at all speeds will be far more economic whilst retaining the reusability of a commercial airliner. The reason that this is now possible is due to the recent improvement in electric motors. They are finally good enough to achieve this capability without adding a lot of additional weight.
The space launch market is predicted to reach US$30 billion in the next few years. The commercial aircraft market is 15 times bigger. The problem is that launching a new commercial airliner is absurdly expensive. It would take endless amounts of startup capital to get a new type of plane into commercial use (many have gone bust trying). This is why there are only two airline manufacturers globally.
The business model for Astro Mechanica is to initially generate large amounts of cash flow from the high margin space launches. Then use this money and flight data to certify a new airline. This airline will be able to travel anywhere on the planet, 3 times faster for the same cost as today. The world is suddenly a lot smaller.
If you want to know more watch this 90 minute interview with the Astro Mechanica founder, Ian Brooke. It gets quite technical but readers with a greater knowledge of engines and aircraft will find it very interesting.
Universal Snake Anti Venom
If you are bitten by a snake, particularly a poisonous snake, you will need a specific anti venom to counteract the poison from the species of snake quickly to survive. This can be problematic if you can’t identify the type of snake that has bitten you. The snake won’t hang around after the bight and show you some ID.
A team from Scripps Research Institute in California has developed an antibody that can block the effects of lethal toxins in the venom of a wide variety of snakes found in Africa, Asia and Australia. The antibody was able to protect mice from bites from black mambas, king cobras and other deadly snakes.
Toxins produced in a laboratory were used to screen billions of different human antibodies in order to identify one that can block the toxins activity. Discovery of this antibody is a big step towards a Universal Snake Anti Venom. A universal anti venom would mean that all hospitals and emergency departments could quickly and safely treat snake bites without needing to identify the specific species of snake responsible for the bite.
The team has previously worked on how neutralizing antibodies against HIV can work by targeting areas of the virus that can not mutate. The quest for a snake anti venom faced a similar challenge. Snake venoms have enough small variations that make antibody binding to one venom different to another. Like HIV, snake venoms have regions that cannot mutate. An antibody targeting that region could possibly work against all variants of snake venom.
The protein called three-finger toxins (3FTx) is present in all elapid snakes (snakes with permanently erect fangs at the front of the mouth) venom. 3FTx is highly toxic and is responsible for whole body paralysis. The team tested human antibodies from a library of 50 billion, to find which ones bound to 3FTx. 30 antibodies were identified in the screening however one, 95Mat5, stood out. 95Mat5 mimics the structure of the human protein that 3FTx usually binds to in the body.
The anti venom is effective against the venom of all elapids however it does not block the venom from vipers, the second group of venomous snakes. The team is now working identifying antibodies that neutralize two viper toxins as well as an another elapid toxin. The cocktail of 4 antibodies should provide a universal snake anti venom.
100,000 people a year die from snake bites (mostly in Africa and Asia). This is more than many tropical diseases. A universal anti venom administered soon after a bite should go a long way to saving these lives.
Superconducting Magnets
A team from MIT and Commonwealth Fusion Systems in Boston have developed a new type of magnet that has achieved a magnetic field strength of 20 tesla for a large scale magnet. This is enough intensity for a fusion power plant.
Previous magnets of this strength were massive and costly. Impractical and economically unviable for fusion systems. This new magnet at a greatly reduced size changed the cost per watt of a fusion reactor by a factor of 40.
The most widely used design for experimental fusion reactors is a Tokamak which uses magnets to hold the plasma where the fusion reactions take place. This new magnet will reduce the size and cost of potential reactors.
A few years ago a new material, rare-earth barium copper oxide (REBCO) was added to fusion magnets. This allowed the magnets to operate at 20 kelvin (versus 4 kelvin for previous magnets). Despite only be 16 kelvin warmer it brings significant advantages in material properties and practical engineering.
Using this new superconducting material allowed the team to rework from the ground up the principles used to build superconducting magnets. The team was able to eliminate the use of insulation around the thin flat ribbons of superconducting tape that formed the magnet. The tape was used to prevent short circuits. In the new magnet the higher conductivity of REBCO kept the current flowing without the need for the insulation.
There is still a long way to go before we can produce commercial fusion energy however this new magnet has been described as the most important breakthrough in the last 30 years of fusion research.
Red Supermassive Black Holes
Images from the James Webb Space Telescope have led researchers from Ben-Gurion University to identify a red gravitationally lensed supermassive black hole from the early universe. The red color suggests that the black hole lies behind a thick veil of dust.
The accretion of material into the black hole emits a lot of radiation that can over shine the host galaxy. This gives the black hole a bright star like appearance. The black hole was part of a cluster of galaxies with a large enough mass to bend spacetime (or the path of light traveling near it) thus creating a gravitational lens. This lens magnifies the background behind the galaxy cluster allowing us to see even more distant galaxies.
The team discovered three compact yet red objects that stood out. Using a numerical lensing model they found that the three red dots were multiple images of the same source object that existed when the universe was only 700 million years old. The color indicated that the object was not a typical star forming galaxy. This together with its’ compact size lead to the conclusion that it was a supermassive black hole.
The black hole’s mass is very high compared to the host galaxy’s mass. This is consistent with other black holes that have been discovered from the early universe. This relationship between the black hole and the host galaxy in the early universe is not well understood. Astronomers do not know which came first, the galaxy or the black hole. Many more similar red dots have recently been detected. We may have an answer in the near future.
Paying it Forward
If you have a start-up or know of a start-up that has a product ready for market please let me know. I would be happy to have a look and feature the startup in this newsletter. Also if any startups need introductions please get in touch and I will help where I can.
If you have any questions or comments please comment below.
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Till next week.