This is the first spacecraft to raise its orbit around the Earth using sunlight.

Weighing just 5 kilograms, this cubeSat (small, standardized spacecraft that have made space flight more affordable), the size of a loaf of bread called LightSail 2 from the Planetary Society, is set to become the first spacecraft to raise its orbit around the Earth using sunlight: it will take off on June 22 aboard a Falcon Heavy Space X rocket from Kennedy Space Center in Florida.

LightSail 2, arrived in space, will deploy a solar sail and attempt to raise its orbit with the gentle thrust of the solar photons. While light has no mass, it has an impulse that can be transferred to other objects. A solar candle takes advantage of this impulse for propulsion.

LightSail 2
The sails, which have a combined area of 32 square metres, will turn towards the Sun during half of each orbit, which will give the spacecraft a small push which in microgravity conditions will be more than sufficient. For about a month after the deployment of the sail, this continuous impulse should increase the orbit of LightSail 2 by a measurable amount.

LightSail 2 will travel into space aboard the Department of Defense Space Test Program (STP-2) mission scheduled for launch on June 22, 2019. This is an unprecedented milestone, according to Planetary Society CEO Bill Nye:

Forty years ago, my professor Carl Sagan shared his dream of using a solar-sailed spacecraft to explore the cosmos. The Planetary Society is realizing the dream. Thousands of people from all over the world came together and supported this mission. We couldn’t have done it without them. Carl Sagan, and his colleagues Bruce Murray and Louis Friedman, created our organization to empower people everywhere to advance space science and exploration.

Science and data say one thing and airlines another: this would be the perfect boarding on an aeroplane.

We are in the age of data, but those who handle it don’t always seem to want to heed what that data reveals. It happens, for example, with boarding the plane before take-off, a tedious process that usually condemns us to long waits, as well as to some tension and stress.

All this could be minimised if airlines paid more attention to the data. Some do, but science is very clear that the boarding method often used is not optimal. Hopefully those who manage that process will read us.

Shipping Methods: There Are Them, There Are Them

A Boeing study long ago revealed that the boarding of an airplane was 50% slower in 1998 than in 1970. We will have made progress on many things, but the rate of passengers entering the plane by the minute has worsened dramatically in recent years.

We already mentioned in the past that there are several shipping methods that have been used over the years. The best known and most popular are the following:

From back to front: if the shipment is from the door closest to the nose, it is normal to find a process that tries to go from the last rows, the closest to the tail, to the first. The aim is to try to avoid crowds in the first rows with people trying to access the last ones.
From outside to inside (“Wilma method”): first the windows, then the intermediate seats and finally the aisle seats.
By seat numbering: a combination of the two above that takes both factors into account.
Random: it does not take into account any of these possible boarding priority parameters and instead chooses rows and seats entirely at random.

To evaluate the differences in these different boarding modes there are studies like Menkes van den Briel’s, the problem is that although in the first few minutes improvements can be noticed between them, they all converge to a very similar end time.

Much more detailed is the fantastic study (PDF) of Jason Steffen, an astrophysicist from the Fermi National Laboratory in Illinois who even devised his own boarding method through his results.

The so-called “Steffen method” organizes boarding in alternate rows with the window seats first moving backwards and forwards. Thus, 12A would be followed by 10A, 8A, etc., and then we would return to 9A, 7A, 5A, and so on, and then fill the middle seats and the aisle seats below.

That theory was singular, but would it really be fulfilled? That’s what a television producer named Jon Hotchkiss proposed to Steffen. To get the idea off the ground, he created a kind of model of a Boeing 757 and had the help of 72 volunteers who acted as virtual passengers.

The result, as shown in the table above, was surprising: the Wilma method was very good, but his method confirmed his theory and was even better at making a shipment in the shortest possible time.

These experiments did not stop there: the popular TV series “Myth Hunters” studied precisely this question in episode 222.

Those responsible for the program simulated the boarding of an airplane with 173 passengers and even took into account realistic situations and indicated to 5% of the passengers that they were “problematic”: to sit in the seat that was not, to travel with children or to lose time by putting their luggage in very quietly and obstructing the passage of other passengers.

In this process there were several curious results, mainly because the boarding time was evaluated as well as the satisfaction of the passengers who boarded. The quickest (except priority, that each passenger choose their place) was the one that generated the worst satisfaction.

The most complete was probably the singular inverse pyramid (priotaries in the first place, after which a “cascade” of zones was used that was dispersed from the rear window seats), above Wilma and Wilma with blocks: it took a little longer than these methods, but it was the one that caused more satisfaction.

There are other equally interesting variants, and one of the most striking is the so-called “magic carpet” which even has its own website and promises the best results. Referring to the program “Myth Hunters” in which the best was the inverse pyramid with about 15 minutes of boarding time, the magic carpet would achieve shipments of 13 minutes that could even be lower.

Studies in this field are surprisingly numerous: we have the Michael Schultz and Hartmut Fricke (2011), plus an update from the same authors and a third contributor, Thomas Kunze (2013).

Even more recent is the work of Shafagh Jafer and Wei Mi (2017) which concludes that the most appropriate method is the Wilma, but we can also run our own simulations with alternatives such as Simul8, whose responsible coincided with the good behavior of the Wilma method.

Time is money, and more in an air plane

It is difficult to know what factors airlines take into account when developing their boarding systems, but it is clear that the economic factor is one of the most important.

In fact, a study of the impact of flight delays published by the University of Berkeley in California showed how an estimate of the total cost of flight delays in the United States cost the industry $32.9 billion, of which $16.7 billion had a “passenger component.

A stopped plane costs between 40 and 337 dollars when stopped, the study said, so saving on boarding times should be a priority for these airlines.

This is another reason why some airlines require different additional payments depending on which cabin baggage we carry or which one we want to check: being clear about what we are going to carry and pay before can save more than a displeasure, and not only does it allow airlines to earn extra revenue, but they can also better organize boarding and reduce times with these measures.

Such measures have become the norm in highly controversial airlines such as Ryanair, which has long charged between EUR 6 and EUR 10 for hand luggage if we are foresighted, but that amount amounts to more than EUR 25 if we carry more hand luggage than is permitted at the boarding gate.

These measures work, of course, and charging more for checking in any type of baggage is one of the systems to increase revenue: in 2016 alone, US airlines received 4.2 billion dollars for this type of payment, accounting for 2.5% of their total revenue that year.

This measure does not comply with the Spanish regulations of the Air Navigation Law, but it is also that the conditions of each airline vary on a fundamental issue such as the measurements of suitcases allowed for cabin luggage, which are different depending on the company. The consensus here is non-existent, something that generates additional stress among passengers.

Some airlines do try to improve on this. American Airlines spent two years studying its boarding processes and came to the conclusion that a partially random system based on zones was the most appropriate. A little later it introduced a modification, and allowed passengers who didn’t need to put anything in the cabin compartments to have priority in boarding.

How are boarding groups created?

Each airline uses different boarding procedures involving different parameters. These parameters include the priority of passengers – whether they are members of loyalty programs, frequent flyers, etc. – what they have paid for the ticket or even the boarding systems they use on that airline.

This means that we may encounter situations that should be analogous in different companies but are not: often those who pay an extra have higher shipping priority.

In the meantime, groups with lower priority may have rented a car next to the passenger or a hotel and a group that embarks later could do so because they have paid only for the ticket without any extra, but this argument is often mixed with others that result in different situations.

In StackExchange they explained for example how in American Airlines for example the priority is for first class passengers, then business class, then high level frequent passengers, low level and then groups 1 to 4.

Group 1 would have paid an extra to board earlier or paid by credit card. In group 2 there would be people who use online check-in or who have a connecting flight with another airline, group 3 is people who use one of the ticketing terminals at the airport and group 4 is people who get a boarding pass with an agent, for example when checking in.

This system is different from United Airlines, which uses very different groups from 1 to 5. Group 1 includes first and business class passengers as well as high level frequent flyers. Group 2 would include the remaining frequent flyers, people who have paid for earlier boarding, and people with United credit cards.

Group 3 would include all passengers who go in window seats, while group 4 would include the remaining passengers who sit in the middle seat and group 5 would include the remaining passengers (aisle seats).

In Spain the same thing happens and each airline has its own procedure. Iberia, for example, has four groups, while uqe Vueling has three different groups and Ryanair, as we explained in depth a few months ago, has its own method of maximising extra revenue after buying the ticket.

There are group boarding processes of all types, and for example Lufthansa has different policies for different types of flight. In the long distance (outside Europe) while Japan Airlines has a process in which after the pre-boarding used by many airlines (people with temporary or permanent disabilities, families with small children) embark priority passengers (First, Business, frequent travelers) and then go to a boarding back to front.

There are many conclusions to be drawn from this analysis. First and foremost, that airlines do not have a unified, standard process that could help make everything easier for passengers, who are disadvantaged by these differences. The second is that economic revenue is once again being sent.

And third, that science and data seem to matter very little: there are theoretically better methods than the airlines use for boarding, but they don’t seem interested in taking advantage of them. As we mentioned at the beginning, let us hope that some of them will read to us and consider changes in a system that would not only be beneficial for passengers, but also for them thanks to time savings.

This robot not only flies, it compresses to enter small spaces.

The FSTAR hybrid (flying sprawl-tuned autonomous robot) is not only a robot capable of flying like a quadricopter, but of driving in difficult terrain and transforming itself to access reduced spaces, using the same engines, as you can see in the following video.

FSTAR will be presented at the 2019 International Conference on Robotics and Automation in Montreal on 21 May.

Developed at Ben-Gurion University in the Negev by Mechanical Engineering professor David Zarrouk and his graduate student, Nir Meiri, the FSTAR adjusts its width to crawl or run on flat surfaces, climb large obstacles and climb very separate walls, or go through a tunnel, pipe or narrow spaces.

He can also run on the ground at speeds of up to 2.6 meters per second, as Zarrouk explains:

We plan to develop larger and smaller versions to expand this family of extensive robots for different applications, as well as algorithms that will help exploit the speed and transport cost of these flying robots/drivers.

NASA funds cryogenic hydrogen system to power all-electric aeroplanes

Advances in engine systems have increased flight efficiency over the last few decades, but dependence on fossil fuels means that aircraft continue to contribute to greenhouse gas emissions.

To solve this problem, NASA, together with specialists from the University of Illinois, proposes the idea of using sustainable energy sources instead of fossil fuels for commercial aircraft, with a view to the introduction of cryogenic hydrogen.


The Center for High Efficiency Cryogenic Electric Technologies for Aircraft (CHEETA) will investigate the technology needed to produce a practical all-electric design to replace conventional fossil fuel propulsion systems. Although the project is still in its conceptual stage, and there are still several technical hurdles to overcome, researchers have a firm vision of the technology and its potential.

Basically, the program focuses on the development of an all-electric aircraft platform that uses cryogenic liquid hydrogen as a method of energy storage.

The chemical energy of hydrogen is converted into electrical energy through a series of fuel cells, which power the ultra-efficient electric propulsion system. The low temperature requirements of the hydrogen system also provide the opportunity to use superconducting or lossless power transmission.

The CHEETA project is a consortium of eight institutions including the Air Force Research Laboratory, Boeing Research and Technology, General Electric Global Research, Ohio State University, Massachusetts Institute of Technology, University of Arkansas, University of Dayton Research Institute and Rensselaer Polytechnic Institute.

Something important for us to start relying on autonomous cars: that they show feedback like humans.

Perhaps, in a short time, we will discover and collectively assume that autonomous cars are much safer than cars driven by humans. However, until that time comes, we are going to have to take intermediate steps to ensure that people do not feel uncomfortable or tense.

When we are going to cross a zebra crossing, for example, we underestimate the importance of creating a mind theory of the car’s conduit that is about to cross just above that zebra crossing as well.

That is, we can make eye contact with the driver, warn that he has seen us, or signal to the driver that we have seen him. That he wants to stop, or that he pretends to continue. All this non-verbal language based on predicting intentions is impossible if the driver of the autonomous car is an algorithm. We cannot create a theory of mind from an algorithm.

First steps

A possible solution to this problem has been proposed by, a company that operates autonomous vans in Texas. The bright orange and blue vehicles have LED signs on all four sides that respond to the context with messages to provide some feedback not only to pedestrians, but also to eventual occupants of the vehicle.

These signals can tell a pedestrian who wants to cross in front of the car something like “I’ll wait for you to pass” or they can warn him: “Wait for me to pass”.

A related strategy is aimed at passengers, not pedestrians: screens on Waymo vehicles show car occupants a simple, animated version of what the autonomous vehicle is seeing. These screens can also show what the vehicle is doing, as if it were stopping to allow a human to cross.

All of which means that if vehicles are predictable and do what they say they will do, people are more likely to trust them. Little by little.

Reducing energy costs associated with cooling buildings by up to 50% is possible with this new wood.

A ‘cooled wood’ can reduce the cost of air conditioning a home by 50%, because this new wood-based material, designed by scientists at the universities of Maryland and Colorado, successfully reflects heat or infrared radiation.

Buildings account for more than 40% of total U.S. energy demand, almost half of which is used for heating and cooling.

Eight times stronger
This wood is eight times stronger than natural wood, is highly reflective and capable of passive radiative cooling.

To achieve this, the researchers improved the qualities of the material by compressing the wood that has been stripped of its lignin (polymers that help harden plant cells), and impregnated it with impressive mechanical and radiative cooling properties.

The complete denitrification and deification process not only makes the wood significantly stronger, but also produces partially aligned cellulose nano fibers, giving the cooling wood its highly solar-reflective surface and high infrared emissivity.

Send your name to Mars with NASA’s Mars 2020 mission

In the form of a boarding pass digitalized on a chip incorporated into the next Mars 2020 mission, NASA has launched a campaign so that anyone who wants to can send their name to Mars.

The Twitter account on the Curiosity rover announced it like this: “Do you want to join me on Mars? Send your name to the surface of the red planet with NASA’s next rover, Mars 2020.

Mars 2020
The tuit is completed with a link to a website that offers the form to fill in for the issuance of the personal boarding pass.

In the first hours, the initiative totaled more than 660,000 names worldwide. Applications close on 30 September.

The Mars 2020 mission is scheduled to be launched in July 2020 from Cape Canaveral, and is expected to arrive in February 2021 at the Jezero crater. Its aim is to investigate the relevant ancient astrobiological environment on Mars, investigate its surface, geological processes and history, including assessment of its past, habitability and possibility of preserving biofirms within accessible geological materials.

Never before has a heavier-than-air vehicle been flown into the thin atmosphere of Mars, and the helicopter NASA wants to send to the Red Planet would be the first of its kind.

This is the “most expensive medicine in the world”: the gene medicine revolution is about to become mainstream.

On Friday, the US FDA gave the green light to Zolgensma, which is already known as “the most expensive drug in the world”. And not for less, since its final price has been set at 2,125,000 dollars. However, if we look only at the price we will be forgetting the most interesting thing about this genetic treatment for spinal muscular atrophy: with dozens of therapies waiting to be approved, its short-term future is also that of gene medicine around the world.

The revolution of gene medicine becomes mainstream

A medicine for SMA. Spinal Muscular Atrophy is an autosomal recessive inherited neuromuscular disease (i.e., both parents must carry the gene responsible for the disease). It affects approximately one in 6,000-10,000 people and manifests itself as a progressive loss of muscle strength caused by the involvement of motor neurons in the spinal cord that prevents nerve signals from being properly transmitted to the muscles (with consequent atrophy).

It is not the only drug available to treat SMA. In Spain, for example, Spinraza was also the subject of controversy a few years ago because of its high price. However, Novartis’ Zolgensma goes one step further because it is presented as the first major gene therapy available to the general public. A therapy that can cure the disease with a single application.

The medicine to come. According to the FDA and if all goes well, in 2025 there will be between 10 and 20 gene therapies in the North American market. Treatments for haemophilia or muscular dystrophy await approval by the highest American authority. Although not only to the approval, of course.

Because the arrival of the Zolgensma opens up many debates, especially regarding the financing of these medicines. Novartis has already started negotiations with US insurance companies to allow payment plans and try to introduce this type of therapy in the clinic at prohibitively expensive prices. Above all, because as has happened again it is reasonable to think that in the next few years the price of these treatments will fall dramatically.

Patients, pharmacists and health systems. In Europe, where the public has a much more important role in health systems, the debate is also open, and we must prepare to deal with it with all the guarantees of transparency and fairness. Last week the BMJ published a report calling into question the close relationship between pharmaceuticals and patient associations in the United Kingdom. The fact that gene medicine is becoming mainstream is great news, but (as we see) in the next few years all the world’s health systems are going to be tested. We need to get down to work.

After a nuclear explosion, these are the foods that become more radioactive

Many of us are currently involved in the extraordinary television series Chernobyl, starring the unsurpassed Jared Harris. So it’s not trivial to wonder what food would become more radioactive as a result of an exposure to radioactivity?

The easiest way to find out is to explore some studies conducted in the “City of Survival,” a fictitious city built in the desert of Nevada, United States, where hundreds of atomic bombs were detonated.

Beware of cod

Project 32.5, a fifteen-page report published in 1956, was intended to test the resistance of frozen foods to a nuclear explosion. To carry out the study, they covered themselves with ice and buried themselves in shallow trenches, 387 and 838 metres, respectively, from the place where a 29-kilometre bomb was to detonate, as well as storing other supplies in freezers in the houses of the city of survival, 1.4 kilometres from ground zero.

29 kilotons, to give you an idea, is twice the power of Hiroshima. So it was more than enough to cover it all with radioactivity. But not all food absorbed it equally, after waiting two and a half days before digging up the food, as Pierre Barthélémy explains in his book Experiments of Improbable Science:

Cod loins turned out to be the most radioactive, ahead of peas. Strawberries had no anomaly. (…) An analysis showed that the nutritional properties had not been reduced, except for a decrease in the vitamin B9 levels of frozen French fries. A team of volunteers also ensured that there were no noticeable differences in taste, texture and appearance from the control foods.

What about food in freezers? There was no sign of radioactivity. However, the report warns that the consumption of food exposed to radiation “should be vitalized as much as possible during the first two weeks, except in case of urgent need.