A selection of important scientific discoveries of 2020

BIOLOGY
. Vaccine for Covid-19
There is no surprise in determining which was the single most important scientific achievement of 2020. It is rare for scientists across the world to work on a single problem of immediate impact on human well-being. This was addressing the challenge of developing a vaccine for Covid-19. There are many virus-caused diseases for which we do not have vaccines, even after years of research: the common flu and the HIV being two of them. That pharmaceutical companies developed Covid-19 Vaccines in record time is a great achievement indeed.

. Dinosaurs
There were many interesting discoveries on dinosaurs last year. Scientists identified the remains of tyrannosaurs so young they had not yet broken free from their shells. Analysis of the remains, which are 71 to 75 million years old, revealed that tyrannosaurs started out surprisingly small, measuring an estimated one metre long, but with an extra-long tail. 

In another find, scientists got an exceptional look at the final hours of a dinosaur's life more than a hundred million years ago, even what it had for its last meal! It was a nodosaur, 110-million-year-old. The ball of fossilized vegetation from its stomach revealed that a few hours before its death, it largely munched on a specific type of fern. The picture shows the nodosaur Borealopelta on display at the Royal Tyrrell Museum in Alberta, Canada.
When you watched Jurassic Park, you assumed that extracting dinosaur's DNA from fossils was easy. So far, scientists have not managed to do it, but 2020 saw stunning progress: a team identified the outlines of cells, forms that may be chromosomes, and several possible nuclei: the structures that house DNA. They have not been able to extract DNA from the fossil cells, however.

. The Great Barrier Reef
Scientists mapping the northern Great Barrier Reef seafloor stumbled on a towering skyscraper of coral more than 550 metres tall, nearly as tall as the tallest buildings on earth. A detached reef, it hosts a variety of lifeforms in its ecosystem. It will take some time to analyse all the data coming, but scientists have already found new species of fish. (Pictures from the BBC).

. Homo Erectus find
Assembling the pieces of a skull found in rocks northwest of Johannesburg, South Africa, scientists were stunned when they realised that they held the first brain-case of Homo erectus found so far, dated to some two million years old. The picture shows the Homo erectus cranium outline. It was put together from more than 150 pieces by an Australian-led team in South Africa. (Photograph: Supplied by La Trobe University).

SPACE

. Bennu Asteroid
Have you touched an asteroid? For the first time, the NASA spacecraft OSIRIS-Rex reached out and grabbed rocks from a 4.5-billion-year-old asteroid named Bennu. The mission took place more than 200 million miles away from Earth, and this was a first. The samples collected will arrive on Earth three years from now. Experts think it may contain water and prebiotic material, the building block of life. Such evidence might offer clues about how life started on Earth. The picture shows OSIRIS-REx readying itself to touch the surface of asteroid Bennu. (Credit: NASA/Goddard/University of Arizona).

. Moon and Planets
We also learned more about our neighbour, the Moon. NASA confirmed water on the sunlit side of the Moon indicating that water may be distributed across the moon's surface, and not limited to the cold and shadowed side.
Farther away, scientists spotted phosphine gas on Venus. This opens up the question of whether there is life on Venus.
Data coming from the InSight Lander on Mars showed a steady hum: a quiet, constant drone that seems to pulse to the beat of “marsquakes” that rattle the planet. This has scientists in a puzzle, as the music of Mars reverberates at a higher pitch than most natural hums on Earth. The sound is truly awesome. If you have access to the internet, please listen to the sound at https://www.nasa.gov/feature/jpl/nasas-insight-hears-peculiar-sounds-on-mars . Watch out for the explanations of the sound you are hearing in the middle of the screen. And now imagine it: you are listening to the sounds from another planet!

. Stars
Betelgeuse is usually among the brightest stars in the sky, but in December 2019, its intense twinkle mysteriously dimmed. Scientists predicted the death of the star, which will be seen as a Diwali style supernova explosion. But by May the star returned to its normal brightness, belying the doom predictions. Now the explanation is that the star very likely expelled a superhot jet of plasma that cooled as it blasted outward. The process formed a cloud of stardust that could have blocked Betelgeuse's light from viewers on Earth. 

THE EARTH
. Global warming
2020 turned out to be one of the hottest years ever recorded, just a little behind 2016. This continues a dangerous trend, with the ten hottest years ever documented all occurring since 2005. Millions of acres in Australia burned from October 2019 into January 2020. In Brazil, fires ravaged the Pantanal, the world’s largest tropical wetland, from July through October. In the USA, California recorded its worst fire season ever, with more than 3 million acres destroyed. The picture shows wildfires in the Arctic (Credit: Down to Earth).

. Microplastics
Plastic debris has infiltrated Earth's water, air and the living tissues of many creatures, including humans. Scientists published several studies showing that microplastics have spread both in quantity and in spread in many habitats around the world. They found microplastics in Antarctic sea ice. They estimated that 15.8 million tons of microplastic are embedded in the Earth's seafloor. They found microplastics on the slopes of Mount Everest, with one sample at 27,690 feet above sea level.

. A world in decline
A World Wildlife Fund report calculated that in just 50 years, humans have decimated two-thirds of the world's wildlife. Since 1970, 4,392 mammals, amphibians, birds, fish and reptile species' population sizes declined by 68 percent. Animals living in Latin America and the Caribbean had their population sizes decreased by 94 percent. 

MEDICINE and DISEASE
. A new gland discovered
You would think our doctors know all there is to know about human anatomy. As scientific instruments and tools expand, we keep learning more, and the human body is no exception. Researchers found a new set of salivary glands in the neck that they named the tubarial glands, hidden between the nasal cavity and throat.

. CRISPR
The 2020 Nobel prize for Chemistry was awarded for development of the CRISPR/Cas9 genetic scissors. Last year, the tool helped in important new therapies: for Leber congenital amaurosis, a rare inherited disease that leads to blindness, for beta-thalassemia and for sickle cell disease.

. Mitochondria and inflammation
Scientists found functioning whole mitochondria in circulation in the blood of healthy individuals. Apparently this can lead to a major impact on learning how inflammations are caused, and can be treated.

. Alzheimer's testing
The first blood test to sample for blood biomarkers indicative of Alzheimer's disease became available for doctors. Apparently nobody expected a breakthrough on this even 5 years ago, but now it is on the market.

. Ebola
With all the focus on Covid-19, people missed an important success story: on June 25, the World Health Organization declared the end of the second largest Ebola outbreak, which infected more than 3,480 and killed nearly 2,300, most of them in the North Kivu province of the Democratic Republic of the Congo. It also declared the end of the outbreak in Equateur of Congo, in Nov, 2020. Unfortunately, there has been a recent outbreak in Kivu, in Feb 2021. Ebola kills almost half the people it infects, although it cannot be spread through the air, unlike Covid.

. HPV
In another piece of good news, the world is on track to eliminate a form of cervical cancer associated with the human papillomavirus (HPV) in another 20 to 30 years. This is mainly because pap smears, introduced 50 years ago, help in early screening, and a vaccine introduced in 2006 prevented HPV infection. The combined effect has been very positive.

. Artificial Intelligence (AI) for Biology
In a very exciting development, AI helped crack a decades-old problem in biology. All proteins start out as a chain of chemical compounds called amino acids. Those chains then fold, twist and turn over and over again into perplexing tangles that eventually develop a three-dimensional shape. This shape determines what the protein can do and cannot, so biologists are keen to know how protein folding takes place. Google's DeepMind has developed a deep-learning tool called AlphaFold that can determine a protein’s structure in a matter of days. This can lead to quicker and more advanced drug discovery.

MATHEMATICS

. Knot theory
Many consider mathematics to be especially a young person's field. In another demonstration of this, Lisa Piccirillo, a young woman PhD student, solved a decades-old question about knots. She proved that the Conway knot (see picture) is not a "slice". (Unfortunately, Conway died of Covid-19 without hearing this news.)

. Dodecahedron
Mathematicians resolved a basic question about the dodecahedron, a 12-sided object (see picture). They showed that it is possible to trace a round trip over the surface of the shape starting at one of the corners without passing through any others. In fact, an infinite number of such paths exist. Mathematicians also solved an old problem about what kind of rectangles can be found by connecting points on a smooth and continuous closed loop. They found that all such loops contain sets of points that define rectangles of any desired proportion.

. Fermat's last theorem
When Fermat's last theorem was finally proved, mathematicians found a bridge connecting certain algebraic equations on one side and a kind of symmetric organization of geometric tilings on the other. Called the Langlands correspondence, mathematicians found stunning structures on the bridge last year, vastly expanding what could be found on both sides, revealing deep number theory.

COMPUTER SCIENCE

. Quantum Computing
In a major advancement, scientists showed that quantum computers calculating with "entangled qubits" can theoretically verify the answers to an enormous set of problems. In the process, they solved two major problems, one in physics on models of particle entanglement, and another in pure mathematics, called the Connes embedding conjecture. The picture shows IBM's new quantum computer.

. Travelling salesman problem
The traveling salesperson problem seeks to find the shortest round trip for any collection of cities. Simple as this sounds, finding an efficient method to solve the problem, or showing that every method would be inefficient, is among the million-dollar challenges. While that challenge remains, scientists used mathematical techniques from what is called geometry of polynomials, to improve the long-standing best method for this problem. Guess how much was the improvement? A difference of "at least" 0.2 billionth of a trillionth of a trillionth of a percent! But scientists are excited by the techniques used, and consider them to be potentially useful for improvements in a variety of other problems.

Sources: The Hindu, National Geographic, The Smithsonian, Quanta