- Astronomers, anthropologists, geologists, and many other scientists have made mind-boggling breakthroughs in the last 10 years.
- Some highlights include work that produced the first image of a black hole, traced what happened to the Neanderthals, and discovered potentially habitable planets outside our solar system.
- These are 41 of the biggest scientific accomplishments of the decade.
In the last decade, scientists around the world pulled off impressive feats: They imaged a supermassive black hole for the first time, discovered new human ancestors, created groundbreaking new medical treatments, and launched probes to distant asteroids, comets, and moons.
These and other accomplishments are improving scientists' understanding of human history, the planet, and the cosmos.
As 2020 — and a new decade — approaches, here's a look back at some of the most awe-inspiring scientific discoveries made during the last 10 years.
In March 2010, anthropologists discovered a tiny, lone finger bone in the Denisova cave in Siberia. They determined it belonged to previously undiscovered species of human ancestor.
Genetic analysis revealed that Denisovans (named after the cave in which they were found) were an enigmatic offshoot of Neanderthals.
Thus far, fossilized Denisovan remains have only been found in Siberia and Tibet. The species disappeared about 50,000 years ago but passed some of their genetic makeup to Homo sapiens. Denisovan DNA can be found in the genes of modern humans across Asia and some Pacific islands; up to 5% of modern Papua New Guinea residents' DNA shows remnants of interbreeding with Denisovans.
People in Tibet today also possess some Denisovan traits — and these traits appear to help Sherpas weather high altitudes.
Just after anthropologists discovered Denisovans, geneticists finished sequencing the entire Neanderthal genome.
While 2010 was a watershed year for anthropology, 2011 was all about achievements in space. NASA sent a new rover to Mars, called Curiosity.
Curiosity is the largest and most capable rover ever sent to Mars. It joined fellow rover Opportunity in searching the red planet for signs of water and clues about whether Mars was ever capable of supporting microbial life.
In November 2011, NASA announced that its planet-hunting Kepler space telescope had spotted its first potentially habitable planet, Kepler 22-b.
Planets in habitable zones are capable of hosting liquid water, one of the requirements for being considered Earth-like.
Impressive achievements in space exploration continued into 2012. NASA's Voyager 1 probe left our solar system and crossed into interstellar space in November of that year.
NASA launched Voyager 1 in 1977. After flying by Jupiter and Saturn, Voyager 1 crossed into interstellar space. It continues to collect data to this day.
In 2019, Voyager 1's successor, Voyager 2, also entered interstellar space. Both probes have been flying longer than any other spacecraft in history.
Voyager 2 has beamed back unprecedented data about previously unknown boundary layers at the far edge of our solar system — an area known as the heliopause. The discovery of these boundary layers suggests there are stages in the transition from our solar bubble to interstellar space that scientists did not previously know about.
Other scientific disciplines made incredible headway in 2012, too. Physicists reported the detection of a new type of particle called the Higgs Boson.
The Higgs Boson is nicknamed the "God particle" because it gives mass to all other fundamental particles in the universe that have mass, like electrons and protons.
Scientists knew a particle akin to the Higgs Boson had to exist — otherwise nothing in the universe would have mass, and we wouldn't exist — but had failed to find evidence of such a particle until 2012.
In 2013, NASA astronomers observed plumes of water vapor being ejected from the frigid, icy surface of Jupiter's moon, Europa.
This discovery made Europa only the second known oceanic world in our solar system aside from Earth; NASA observed jets of water vapor spewing from Saturn's moon Enceladus in 2005.
The presence of liquid water and ice make these two moons ideal places to search for life in our corner of the galaxy.
Since 2013, water has also been discovered on the dwarf-planet Pluto, a moon of Neptune called Triton, and multiple other moons of Jupiter and Saturn.
That year, NASA's Curiosity rover uncovered evidence that the red planet not only once held liquid water, but may also have been habitable.
In September 2012, NASA announced its Curiosity rover had identified gravel made by an ancient river in Mars' Gale Crater.
Then in March 2013, scientists found chemical ingredients for life — sulfur, nitrogen, hydrogen, oxygen, phosphorus, and carbon — in powder that Curiosity had drilled from rock near the ancient streambed.
"A fundamental question for this mission is whether Mars could have supported a habitable environment," Michael Meyer, who worked as the lead scientist for NASA's Mars Exploration Program at the time, said in a press release about the finding. "From what we know now, the answer is yes."
In the following years, evidence has mounted that the planet was once home to a vast ocean.
In November, physicists discovered 28 strange particles called neutrinos buried deep under the Antarctic ice. These neutrinos, they concluded, came from outside our solar system.
Researchers found the particles using the IceCube Neutrino Observatory, an array of sensors embedded in Antarctic ice. Neutrinos are nearly mass-less and unstoppable; they move at the speed of light and get discharged in the aftermath of exploding stars.
Scientists can use neutrinos to understand events happening in distant galaxies. In 2018, they found more of the particles in Antarctica, then traced them back to the source: a rapidly spinning black hole, millions of times the mass of the sun, that's gobbling up gas and dust.
The European Space Agency got some time in the spotlight in 2014. In November, the agency's Rosetta space probe landed on a comet 372 million miles from Earth called 67P/Churyumov-Gerasimenko.
It took Rosetta 10 years to reach the comet, enter its orbit, and send a lander down to the surface.
Rosetta's lander, Philae, took the first-ever surface images of a comet.
In 2015, anthropologist Lee Berger announced that his team had discovered a new human ancestor species called Homo Naledi in South Africa.
Two spelunkers had accidentally stumbled across the Homo naledi fossils two years earlier, in a hidden cave 100 feet below the surface.
All told, the chamber contained 1,550 bones belonging to at least 15 individuals who lived between 330,000 and 250,000 years ago.
That was also the year that scientists mapped the human epigenome for the first time.
The epigenome is made up of chemicals and proteins that can attach to DNA and modify its function, turning our genes on and off.
An individual's lifestyle and environment — factors like whether they smoke or what their diet looks like — can prompt sometimes deadly changes in their epigenome that can cause cancer.
Mapping the epigenome can help scientists understand how tumors develop and cancer spreads.
Humanity visited Pluto for the first time in 2015, when NASA's New Horizons probe flew by the dwarf planet.
New Horizons spent 15 minutes flying close to the dwarf planet and collecting as much information as possible. After that, it moved on for a close encounter with Pluto's largest moon, Charon.
Another NASA spacecraft, Cassini, achieved new heights in 2015. Astronomers confirmed that a liquid ocean exists under the icy crust of Saturn's moon Enceladus.
NASA's Cassini spacecraft found that Enceladus emits plumes of water into space following the probe's arrival at Saturn in 2004. In 2015, scientists confirmed that the source of these plumes was a giant saltwater ocean hidden beneath the moon's icy crust.
IN 2016, AN ARTIFICIAL-INTELLIGENCE PROGRAM FROM GOOGLE'S DEEPMIND DIVISION, CALLED ALPHAGO, BEAT THE WORLD CHAMPION OF THE STRATEGY GAME GO IN FOUR OUT OF FIVE MATCHES.
That wasn't the first time AI had beat humans in a complex game.
In 2011, IBM's supercomputer, Watson, defeated two "Jeopardy!" champions in a three-day contest.
A year after AlphaGo's success, an AI named Libaratus beat four of the world's top professional players in 120,000 hands of no-limit, two-player poker. Then in 2019, another DeepMind AI program named AlphaStar bested 99.8% of human players in the popular video game "Starcraft II."
PHYSICISTS REJOICED IN 2016 WHEN THEY DETECTED GRAVITATIONAL WAVES FROM THE COLLISION OF TWO BLACK HOLES A BILLION LIGHT-YEARS AWAY.
The catastrophic collision created ripples in space-time also known as gravitational waves. Einstein predicted the existence of gravitational waves in 1915, but he thought they'd be too weak to ever pick up on Earth. New detection tools have proved otherwise.
This collision was the first event scientists had ever observed using gravitational-wave detectors. Then in 2017, they observed two neutron stars merging. In August 2019, astrophysicists detected the billion-year-old aftermath of a collision between a black hole and a neutron star.
THE SAME YEAR, ASTRONOMERS SPOTTED EVIDENCE THAT A MYSTERIOUS PLANET OR OBJECT 10 TIMES THE SIZE OF EARTH ORBITS IN THE OUTER SOLAR SYSTEM. THEY NICKNAMED IT "PLANET 9."
"For the first time in over 150 years, there is solid evidence that the solar system's planetary census is incomplete," one of the planet's discoverers said.
IN 2017, GEOLOGISTS ANNOUNCED THEY'D DISCOVERED A NEW CONTINENT, CALLED ZEALANDIA, HIDDEN UNDER THE PACIFIC OCEAN.
The lost land of Zealandia sits on the ocean floor between New Zealand and New Caledonia.
It wasn't always sunken – researchers have found fossils that suggested plants and organisms once lived there. Some argue that Zealandia should be counted alongside our (more visible) seven continents.
In 2019, scientists found that another ancient continent had slid under what is now southern Europe about 120 million years ago. The researchers named this continent Greater Adria. Its uppermost regions formed mountain ranges across Europe, like the Alps.
THAT YEAR BROUGHT A NEW BREAKTHROUGH IN GENETICS, TOO: SCIENTISTS SUCCESSFULLY CREATED SYNTHETIC DNA.
All living creatures' DNA is made up of two types of amino acid pairs: A-T (adenine – thymine) and G-C (guanine – cytosine). This four-letter alphabet forms the basis for all genetic information in the natural world.
But scientists invented two new letters, an unnatural pair of X-Y bases, that they integrated into the genetic alphabet of E. coli bacteria.
Floyd Romesburg, who led the research, told Business Insider that his invention could improve the way we treat diseases. For example, it could change the way proteins degrade inside the body, helping drugs stay in your system longer.
Romesburg said his team will continue investigating how the finding might help cancer treatments and drugs for autoimmune diseases.
ASTRONOMERS WITNESSED ANOTHER INTERSTELLAR COLLISION IN 2017. WHEN TWO NEUTRON STARS COLLIDED, SCIENTISTS WERE ABLE TO SEE HOW ALL THE GOLD IN THE UNIVERSE WAS CREATED.
The two massive, exploded stars hit each other at one-third the speed of light and created gravitational waves. Scientific instruments on Earth picked up the waves from that crash, an event astronomers say only happens once every 100,000 years.
The crash happened 130 million light years away from Earth, researchers discovered. It caused the formation of $100,000,000,000,000,000,000,000,000,000 worth of gold and produced huge stores of silver and platinum, too.
That year, researchers at a Hawaiian astronomical observatory also observed the first interstellar object ever seen in our solar system: 'Oumuamua.
Scientists only had a few weeks to study the interstellar interloper before it got too far and too dim to see with Earth-based telescopes.
Guesses as to what the object is run the gamut from comet to asteroid to alien spaceship. Harvard astronomer Avi Loeb has speculated that 'Oumuamua was an extraterrestrial scout, but nearly all other experts who have studied 'Oumuamua say that hypothesis is extraordinarily unlikely.
Chinese geneticist He Jiankui announced he had genetically modified human embryos.
Jiankui said he'd edited genes using CRISPR technology in a pair of twins born in China in November. The change, he said, meant the babies were born immune to HIV.
This type of genetic manipulation is banned in most parts of the world, since any genetic mutations that the babies may have would get passed on to their offspring, with potentially disastrous consequences.
In 2019, the MIT Technology Review released excerpts from Jiankui's research. The unpublished manuscripts revealed that in the process of trying to manipulate the babies' HIV resistance — which some experts say was unsuccessful — Jiankui may have introduced unintended mutations.
In 2018, NASA launched another rover to the red planet. InSight touched down on November 26.
NASA's InSight lander spent more than six months careening through space before it landed safely on Martian soil.
The robot is charged with exploring Mars' deep interior and helping scientists understand why Mars wound up a cold desert planet while Earth did not.
InSight has given scientists the unprecedented ability to detect and monitor Mars quakes — seismic events deep inside the planet.
On January 1, 2019, NASA's nuclear-powered New Horizons spacecraft flew past a mysterious, mountain-sized object 4 billion miles from Earth.
The object, called MU69, is nicknamed Arrokoth, which means "sky" in the Powhatan/Algonquian language (it was previously nicknamed Ultima Thule). It's the most distant object humanity has ever visited.
The New Horizons probe took hundreds of photographs as it flew by the space rock at 32,200 miles per hour.
Images revealed that Arrokoth is flat like a pancake, rather than spherical in shape. The unprecedented data will likely reveal new clues about the solar system's evolution and how planets like Earth formed, though scientists are still receiving and processing the information from the distant probe.
Over 5.5 million miles from Earth, a Japanese spacecraft landed on the surface of an asteroid called Ryugu in July.
In order to collect samples from deep within the space rock, Hayabusa-2 blasted a hole in the asteroid before landing. The mission plan calls for the probe to bring those samples back to Earth. By studying Ryugu's innermost rocks and debris — which have been sheltered from the wear and tear of space — scientists hope to learn how asteroids like this may have seeded Earth with key ingredients for life billions of years ago.
In April 2019, the Event Horizon Telescope team published the first-ever image of a black hole.
The unprecedented photo shows the supermassive black hole at the center of the Messier 87 galaxy, which is about 54 million light-years away from Earth. The black hole's mass is equivalent to 6.5 billion suns.
Though the image is somewhat fuzzy, it showed that, as predicted, black holes look like dark spheres surrounded by a glowing ring of light.
Scientists struggled for decades to capture a black hole on camera, since black holes distort space-time, ensuring that nothing can break free of their gravitational pull — even light. That's why the image shows a unique shadow in the form of a perfect circle at the center.
2019 was a big year for medical sciences, too. After three decades of research and development work, the world's first malaria vaccine program began in April.
In the pilot program, children up to 2 years old in Malawi, Ghana, and Kenya can receive the vaccine. The new vaccine prevented four in 10 malaria cases in clinical trials, including three in 10 life-threatening cases.
Malaria kills about 435,000 people each year, most of them children.
"We need new solutions to get the malaria response back on track, and this vaccine gives us a promising tool to get there," Tedros Adhanom Ghebreyesus, director-general of the World Health Organization, said in a release. "The malaria vaccine has the potential to save tens of thousands of children's lives."
In December, the World Health Organization (WHO) prequalified an Ebola vaccine for the first time, a critical step that will help speed up its licensing, access, and roll-out.
The two new treatments, called REGN-EB3 and mAb-114, are cocktails of antibodies that get injected into people's bloodstreams. These therapies saved 90% of new infected patients in the Congo after the WHO declared the Ebola outbreak in Africa to be a global health emergency.
Morgan McFall-Johnsen contributed to this story.
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