A Decade of Innovation

To mark the end of the 2010s, we at the Science department wrote about our favorite experimental innovations of the decade and organized them in an awe-inspiring timeline representing the greatest pillars of scientific progression.

2010: The Discovery of the Denisovans

By Angelina Chang

Scientists identified a 40,000-year old pinky bone in a Siberian cave that was linked to a new hominid species in March 2010. Anthropologists previously thought Neanderthals and humans were the only hominids during the Late Pleistocene, which was 12 thousand to 126 thousand years ago, but the discovery of the pinky bone challenged this idea. Svante Paabo, a geneticist at the Max Planck Institute, and his colleague discovered the bone in the Denisova Cave in southern Siberia. After sequencing DNA from the specimen’s mitochondria, they found that it was genetically similar to both Neanderthal and human DNA but distinct enough to be a separate species of human. Scientists named the species “Denisovan” after the cave the pinky bone was found.

Geologist Chen Fahu and his colleagues published a paper in “Nature” magazine about the discovery of a Denisovan mandible from the Tibetan Plateau in Xiahe County, Gansu, China in 2019. It is the first confirmed Denisovan fossil outside of the Denisova cave, and it was found to be at least 160 thousand years old.

Scientists have found genetic overlap between the Denisovan genome and that of the Melanesians living in Papua New Guinea. The most likely reason is that Denisovans living in eastern Eurasia interbred with the ancestors of Melanesians. Tibetans and Han Chinese have Denisovan DNA in their genomes as well; scientists discovered Sherpas likely inherited a Denisovan gene that allows them to breathe at high altitudes.

2011: The Commercialization of Space Travel

By Gerard Lin

With the conclusion of the American Space Shuttle program in 2011, private companies stepped in to fill the void in space travel that NASA left. Just a year after the last mission of the Space Shuttle program, SpaceX, a private aerospace company founded by Elon Musk, launched the first commercial resupply mission to the International Space Station (ISS). Though this was an unmanned mission, it proved to be an important stepping stone to getting American astronauts in space again.

Another proof of concept for commercial space flight was demonstrated when SpaceX later launched its Falcon 9 rocket and landed it upright, the first instance of a rocket being recovered from an orbital flight. Jeff Bezos’s aerospace company Blue Origin managed to accomplish a similar feat earlier than SpaceX; Blue Origin, however, launched a smaller rocket that completed a suborbital flight. Normally, rockets would be discarded or destroyed during re-entry, so future flights would require the rockets to be built again from scratch, costing millions more than if they were reused from the previous flight.

The most significant accomplishment of the era of commercial spaceflight so far is the launching of the Crew Dragon capsule by SpaceX, which launched two American astronauts to the ISS on May 30, 2020, making them the first commercial company to send American astronauts to space since the Space Shuttle program. With this launch, a private company accomplished something that formerly could only be attained by nations, proving that a private sector of spaceflight was successful and sustainable.

2011: The First Artificial Organ Transplant

By Arin Faruque

Swedish scientists performed the first synthetic organ transplant in July 2011, and by doing so, they successfully saved a 36-year-old patient who suffered from late-stage tracheal cancer. Chemotherapy and radiation therapy were ineffective. The tumor was still growing and seemed to be heading toward the patient’s main bronchus. After no windpipe donor was found, doctors had to resort to their last option: developing and transplanting an artificial windpipe.
To create this synthetic windpipe, scientists created a scaffold from a porous polymer and took stem cells from the patient’s bone marrow. These stem cells were then grown into tissue using a bioreactor. This treatment not only eliminates the need for an organ donor but is also safer than a donor transplant. With traditional organ donor transplants, there always remains a risk that the organ could be rejected by the patient’s immune system. To counter that risk, patients getting donor transplants often have to take dangerous immunosuppressant drugs, whose side effects can be fatal. However, this process completely removes the need for these harmful drugs because the organ being transplanted is derived from the stem cells of the patient themself.

Not only did this case give hope to many patients suffering from tracheal cancer, but it also showed promise for the future of regenerative medicine and brought forward the possibility of a safer way to treat cancers and other diseases.

2012: The Discovery of the Higgs Boson

By Jenny Liu

Physicists at the European Organization for Nuclear Research made history with the discovery of the Higgs boson in 2012, a game-changer in the field of particle physics, a branch of physics that studies the nature of particles in matter and radiation.

The Higgs boson proves the existence of the Higgs field, a ubiquitous field of energy that pervades our entire universe and supposedly gives mass to elementary particles.

Elementary particles are the smallest building blocks of life because they have no structure and cannot be divided. The two types of fundamental particles are known as the fermions, which make up matter, and the bosons, which carry forces. As the particles travel through the Higgs field, they gain mass; the more they interact with the field, the more mass they gain.

The role of the Higgs boson is that it is the excitation of the Higgs field which all fundamental particles result from. The Higgs boson enables the Higgs field to move from a low state of energy to a high state of energy, thus exciting it. That energy then allows the particles that interact with the field to gain mass.

Though we have confirmed its existence, there is still much to learn about the Higgs boson, including its role in antimatter and dark matter. It’s a promising discovery that opens up many avenues for exploration as to how we understand the mass and matter that constitute our universe.

2012: Voyager 1 Leaves the Solar System

By Henry Cen

Voyager 1 officially became the first man-made object to reach interstellar space in August 2012. After more than 37 years of roaming the cosmos, Voyager 1 made history with this achievement.

Voyager 1 launched on September 5, 1977. The Voyager missions took advantage of a special alignment of the outer planets that would allow for a fly-by of four planets, Jupiter, Saturn, Uranus, and Neptune, all while using the minimum amount of propellant and in the least time possible.

After Voyager 1 had accomplished its original mission of flying by Jupiter and Saturn, NASA determined that Voyager 1 still had the necessary power and instruments to continue on, and allowed it to. It continued to fly toward the end of the heliosphere, a bubble region around the Sun made of charged particles and magnetic fields that the Sun emits. Space beyond this bubble is considered interstellar space.

Voyager 1’s position in space was able to be pinpointed through help from a random powerful solar eruption that happened sometime between April and May 2012. This solar eruption created a plasma wave that caused electrons near Voyager 1’s location to vibrate. Voyager 1’s onboard plasma wave instrument sensed these vibrations, prompting it to measure the density of electrons nearby. This information was sent back to scientists on Earth, who concluded that the measured and expected electron densities were consistent. From these conclusions and a few calculations, they reported that Voyager 1 had crossed into interstellar space sometime around August 25, 2012.

2013: The Development of CRISPR-Cas9 for Genome Editing

By Dean Chen

Through a number of diverse mechanisms, the CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) system confers adaptive immunity upon prokaryotic cells. The system functions by integrating foreign DNA into a genomic CRISPR array, which can then be used to identify and cleave identical DNA sequences when encountered again. Cas proteins, or CRISPR-associated proteins, are the agents that facilitate the CRISPR response.

Biochemists Emmanuelle Charpentier and Jennifer Doudna published a paper outlining the potential use of the Cas9 protein for gene editing in 2012. Their research concluded that the synthesis of a single-stranded “guide RNA” was sufficient in inducing the recognition and double-stranded cleavage of target DNA strands. Carpentier and Doudna’s research opened the possibility of a simple, programmable gene-editing system to the scientific world.

Bioengineer Fang Zheng and colleagues confirmed the findings of Charpentier and Doudna in 2013. They succeeded in demonstrating the viability of Cas9 systems in mammalian cells for targeted genetic modification. The team was able to use the proposed Cas9 system for targeted cleavage, insertion, and deletion within human and mouse cells in vitro.

The CRISPR-Cas9 system has opened the door for efficient edits in prokaryotic and eukaryotic genomes and only continues to be expanded upon. It has seen applications in agriculture, gene therapy, and genetic research, though more recent ethical concerns regarding germline editing have influenced research. However, the potential that CRISPR-Cas9 editing has on the biomedical stage remains—more complex and extraordinary uses for it will undoubtedly arise in the near future.

2013: Scientists Create the First Living Human Mini-Brain

By Claire Shin

Developmental biologist Madeline Lancaster discovered a way to use pluripotent stem cells––the primitive cells, present at conception, that have the potential to develop into any bodily cell type––to create living mini-models of human brains in 2013. In order to prod stem cells into becoming brain cells, Lancaster used a process called directed differentiation, which essentially manipulates cell cultures and other cell growth factors to imitate the natural mechanism by which stem cells decide which body cell type they will become. In the right environment, these undeveloped cells will, in the words of Lancaster herself, “spontaneously self-organize” to form what looks like the precursor to an early human embryonic brain. Biologists call these primeval structures organoids (mini-organs); the specific ones in Lancaster’s study are called cerebral organoids.

These models can be used for in-depth research on neurodevelopmental disorders like microcephaly, a birth defect causing children to have much smaller heads (and often lesser-developed brains) than normal. They’re also being used for a more metaphysical purpose: determining what makes us human. By introducing mutations into the stem cells, researchers will be able to identify the uniqueness of human brain evolution that sets us apart from primates and other mammals.

There are clear ethical concerns with experimenting on these miniature human brains: researchers don’t know enough about them to gauge whether they can feel pain or develop a consciousness. Regardless, the promise held by cerebral organoids and stem cell research as a whole is undeniable.

2014: The Synthesis of Artificial DNA

By Kaitlyn Lee

DNA, the molecule that carries the genetic instructions for almost all organisms to function, has always consisted of four nucleotide bases: adenine, guanine, cytosine, and thymine. However, The Scripps Research Institute (TSRI) in California synthesized two new paired bases known as “X” and “Y” that can be added to the DNA structure without disruption of its function in 2014. In addition, the X and Y bases are able to carry out the functions of their original counterparts, such as retrieving information and synthesizing proteins. The creation of the X and Y bases has not only expanded the genetic alphabet of DNA but also opened the possibilities of building new proteins and creating more efficient, long-lasting drugs with fewer side effects.

The scientists of TSRI used genetic engineering to place the X and Y bases into the DNA of Escherichia coli bacteria, which were able to store the bases and pass them to its daughter cells. The X and Y bases were then integrated into bacterial genes that consisted of the four original bases. The bacteria successfully read the artificial bases and transcribed them into its RNA molecules in order to begin the production of proteins. The protein produced through the RNA transcription of the artificial bases contained unnatural amino acids. As a result, the addition of the X and Y bases to DNA molecules allows for the synthesis of 152 new amino acids in addition to the original 20 natural amino acids.

2015: LIGO Detects A Gravitational Wave For The First Time

By Rania Zaki

The Laser Interferometer Gravitational-Wave Observatory (LIGO) Scientific Collaboration in September 2015 detected distortions in the space-time curvature produced by the cataclysmic event of two black holes accelerating and colliding into each other. These distortions produced by accelerating objects, named gravitational waves, affirmed Albert Einstein’s conjecture and paved an unprecedented window into the cosmos.

LIGO’s L-shaped detectors utilized laser interferometers, a technique that allows for the high precision measurement in the time it takes light to travel between suspended mirrors using a controlled laser beam. At the end of each equivocally-distanced arm in the detectors were suspended mirrors that reflected light back. When no gravitational waves were present, the time in which light was reflected from each arm was the same. When a burst of the gravitational waves passed through the LIGO detector, the waves slightly lengthened—specifically a shift of a millionth of a millionth of a millionth of a meter––one arm while compressing the space-time fabric of the other arm. This affected the time it took light to be reflected back. LIGO detected this in both detectors in Louisiana and Washington, affirming the presence of gravitational waves than a near disturbance like a nearby highway.

There is still much to discover. For once, scientists do not know how to analyze gravitational waves that carry extremely preserved information about celestial objects. As their detection and future technology allow scientists to analyze them, the limit to understanding the cosmos will be infinite. LIGO’s detection is a pivotal step in that direction.

2015: The First Mapping of the Human Epigenome

By Sonya Sasson

The human genome is both fascinating and complex, containing nearly three billion DNA base pairs that make each individual unique. Even more complex, however, is the epigenome, the multitude of chemical compounds that direct the DNA itself through various processes, including protein synthesis and cell replication. These molecules are responsible for turning different genes “on” and “off,” resulting in cell specialization within our body. More importantly, the disruption of these chemicals can play large roles in the onset of several diseases, including cancer, Alzheimer’s, and autism.

Researchers released the most complete mapping of the human epigenome in history in February 2015. This groundbreaking achievement was attained in a study led by MIT professor Manolis Kellis in which researchers analyzed a total of 150 billion genome sequences by looking for epigenomic changes between 111 different cells. Kellis explained that “by studying these combinations systematically, we can learn the language of the epigenome and what it is telling us about both the activity and the function of each genomic region in each of the cell types.”

The mapping of the epigenome proved instrumental in the treatment of cancer. Kellis realized that certain proteins within the epigenome were responsible for shutting off cellular restrictions on growth factors and other processes that can lead to cancer. The idea of manipulating the epigenome rather than the DNA itself influenced several experimental theories still researched today. These so-called “epigenetic therapies” focus on reprogramming cancer cells to a normal state to allow for the recovery of the affected genes.

2016: The First Virtual Reality Headsets

By Riona Anvekar

Palmer Luckey created the Oculus Rift, the first virtual reality headset allowing customers to be immersed in a 3D world, in 2016. The headset utilizes stereoscopy to create a 3D effect. Since the eyes perceive the world through two slightly different angles, stereoscopy takes two panels and places them at slightly different angles similar to how your eyes perceive the world. So when the lenses are put together, the brain is tricked into reshaping the images to create a 3D view as it would in real life. To supplement the stereoscopy technique, the headset has embedded sensors that monitor the customer’s head motions and adjust the images on the panel accordingly. Altogether, the headset creates the sensation of being in a 3D world.

To create the images portrayed on the panels, virtual reality developers take the rules that the brain has built from past experiences to interpret the world, and they apply them to the images. For instance, moving objects have to obey the customer’s expectations of the laws of physics. Also, shading and texture should allow the customer to determine depth and distance appropriately. Virtual cues that don’t obey the brain’s rules can make customers feel disoriented or nauseated. The Oculus Rift created the first virtual reality experience engaging visual sensory and will hopefully lead to multisensory integration of virtual reality experiences that will have the power to completely immerse customers in visionary worlds.

2016: Machine Learning Trumps Humans

By Daniel Gordon

In 2016, the world witnessed the astonishing power of machine learning when Google DeepMind’s artificial-intelligence program, AlphaGo, beat Lee Sedol, the best Go player in the world.

Millions of people betted on Sedol to win. After all, he was considered to be the toughest Go player to beat. However, they didn’t factor in just how powerful AlphaGo, a piece of distributed software supported by a team of more than 100 scientists, really was. The software was always improving, playing itself millions of times. It progressively revised its algorithms based on which sequences resulted in a higher win percentage. It did not take breaks. Unlike a human, who must fulfill daily tasks like eating and sleeping to function, AlphaGo’s only activity involved furthering its competence in the strategy game. After beating other Go computer programs and human professionals, only Sedol remained. In a shocking manner, AlphaGo outplayed Sedol 4-1 in a 5-match series.

While the feat isn’t as impressive as some of the accomplishments that advancing machine learning and artificial intelligence can achieve in the future, it reminds humanity of how powerful objective machines can be. The fact that computer software was able to outdo the best human in the world at something demonstrates that the developments in machine learning are virtually endless. Removing the possibility of human error and the ability to constantly iterate sequences promise to push the capabilities of artificial intelligence to unimaginable heights. It’s only a matter of time until machines take over all aspects of our lives.

2017: An Interstellar Visit

By Kristoff Misquitta

Millennia after astronomers studied the stars with rudimentary telescopes and ancient astrolabes, researchers at Hawaii’s Haleakala Observatory identified our solar system’s first tourist.

“Oumuamua,” meaning “a messenger from afar arriving first” in Hawaiian, is an asteroid-like comet believed to have tumbled through the Milky Way for hundreds of millions of years before encountering our solar system. Now, three years since its discovery, it’s beyond the orbit of Saturn and will never return, following a hyperbolic path into the emptiness of outer space.

Oumuamua is unlike any object astronomers have seen before: it’s a record-setting 10 times longer than it is wide, and its speed is far too high (54.4 miles per second) to be attributed to the Sun’s gravitational influence alone. Though its trajectory can be traced back to the bright star Vega, projections mysteriously suggest that Vega wasn’t actually close to the comet when it was there 300,000 years ago. And contrary to the imaginative suggestions that Oumuamua is an alien spaceship, astronomers have confirmed that it is of “purely natural origin.”

Oumuamua’s elongated shape has inspired new hypotheses about the influence of gravitational stretching on the formation of celestial objects, and its mass has sparked new theories about the ejection of small bodies from giant planets.

Despite the perplexing questions it raised, Oumuamua’s passing continues to be a one-of-a-kind, rich source of answers for researchers seeking to better understand our galaxy.

2018: The First Genetically Modified Babies are Born

By Oscar Wang

It would seem that two ordinary babies were born in October 2018 in Shenzhen, China. However, their genes say otherwise: the twins, named Lulu and Nana, were genetically modified as embryos to be resistant to HIV. The scientist responsible for this is named He Jiankui. He conducted experiments on embryonic gene editing to solve fertility issues using in vitro fertilization, or the process in which the egg is fertilized outside one’s body. With the consent of the parents, he used CRISPR to modify the genes of the embryo. The project was conducted in secrecy until he announced his success in November, spurring international controversy.

Jiankui and his associates were punished for unethical conduct and document forgery with three years in prison and a fine equivalent to $430 thousand. The forged document in question was his ethics approval application at a hospital in Shenzhen.

Most notably, this affair led to extensive discussions on the state of medical ethics and how gene editing should proceed. Scientists agreed that the mutations put the babies at risk for other diseases, calling for a temporary ban on embryonic gene editing. Later, the Chinese government drafted regulations that punish the modification of the human genome. As a result, Chinese researchers fear that they won’t receive approval for future CRISPR experiments.

Another article published by MIT over a year later criticizes Jiankui’s practices, highlighting his team’s mistakes. Though the experiments did not end progress on CRISPR, they facilitated a crucial discussion on the future of genetic engineering.

2019: The First Image of the Black Hole

By Shah Nabil

Scientists were able to take the first-ever image of a black hole 55 million light-years away in 2019, which was done through the implementation of the Event Horizon Telescope (EHT). The image showed a large black hole in galaxy M87, in which the scientists were able to capture the hot gas that surrounded the black hole. This breakthrough stunned the entire world since having the image of a black hole is the first step in understanding the mysterious space phenomenon.

A black hole is an area in space that has an immensely strong gravitational pull to where light and other particles cannot move away from it. There have been scientists that studied black holes in the past, such as Albert Einstein (with general relativity) and Stephen Hawking (with Hawking radiation). These concepts have been theoretically discussed and shown in the past, yet until now there was never a physical image that provided more evidence for the black hole’s properties.

The black hole picture was created through the EHT, which consists of several telescopes working in sync to implement a process called the Very Long Baseline Interferometry (VLBI). The idea of processing a clear picture of an area that is millions of light-years away requires a large aperture (diameter) for a telescope. VLBI allows this to occur through several telescopes syncing together, which is what happened with the EHT. The first picture of the black hole is something that we will never forget in history.